CA1249107A - Latex treated cationic cellulose product and method for its preparation - Google Patents
Latex treated cationic cellulose product and method for its preparationInfo
- Publication number
- CA1249107A CA1249107A CA000474317A CA474317A CA1249107A CA 1249107 A CA1249107 A CA 1249107A CA 000474317 A CA000474317 A CA 000474317A CA 474317 A CA474317 A CA 474317A CA 1249107 A CA1249107 A CA 1249107A
- Authority
- CA
- Canada
- Prior art keywords
- product
- cellulose
- dimethylamine
- group
- polymer
- Prior art date
- Legal status (The legal status is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the status listed.)
- Expired
Links
- 238000000034 method Methods 0.000 title claims abstract description 25
- 229920002678 cellulose Polymers 0.000 title claims description 34
- 239000001913 cellulose Substances 0.000 title claims description 33
- 125000002091 cationic group Chemical group 0.000 title claims description 16
- 229920000126 latex Polymers 0.000 title abstract description 46
- 239000004816 latex Substances 0.000 title abstract description 39
- 238000002360 preparation method Methods 0.000 title description 7
- ROSDSFDQCJNGOL-UHFFFAOYSA-N Dimethylamine Chemical compound CNC ROSDSFDQCJNGOL-UHFFFAOYSA-N 0.000 claims abstract description 38
- 239000000463 material Substances 0.000 claims abstract description 20
- QGZKDVFQNNGYKY-UHFFFAOYSA-N Ammonia Chemical compound N QGZKDVFQNNGYKY-UHFFFAOYSA-N 0.000 claims abstract description 18
- NAQMVNRVTILPCV-UHFFFAOYSA-N hexane-1,6-diamine Chemical compound NCCCCCCN NAQMVNRVTILPCV-UHFFFAOYSA-N 0.000 claims abstract description 18
- -1 aliphatic diamine Chemical class 0.000 claims abstract description 11
- BRLQWZUYTZBJKN-UHFFFAOYSA-N Epichlorohydrin Chemical compound ClCC1CO1 BRLQWZUYTZBJKN-UHFFFAOYSA-N 0.000 claims abstract description 10
- 125000000129 anionic group Chemical group 0.000 claims abstract description 10
- 229910021529 ammonia Inorganic materials 0.000 claims abstract description 9
- 239000003431 cross linking reagent Substances 0.000 claims abstract description 7
- 229920000642 polymer Polymers 0.000 claims description 32
- 229920002689 polyvinyl acetate Polymers 0.000 claims description 23
- 239000011118 polyvinyl acetate Substances 0.000 claims description 16
- 239000000839 emulsion Substances 0.000 claims description 15
- 239000000203 mixture Substances 0.000 claims description 15
- 238000004132 cross linking Methods 0.000 claims description 13
- NIXOWILDQLNWCW-UHFFFAOYSA-N acrylic acid group Chemical group C(C=C)(=O)O NIXOWILDQLNWCW-UHFFFAOYSA-N 0.000 claims description 10
- 239000004800 polyvinyl chloride Substances 0.000 claims description 10
- 229920000915 polyvinyl chloride Polymers 0.000 claims description 10
- 239000000654 additive Substances 0.000 claims description 9
- 229920001400 block copolymer Polymers 0.000 claims description 9
- 229920000578 graft copolymer Polymers 0.000 claims description 9
- 230000000996 additive effect Effects 0.000 claims description 8
- NLHHRLWOUZZQLW-UHFFFAOYSA-N Acrylonitrile Chemical compound C=CC#N NLHHRLWOUZZQLW-UHFFFAOYSA-N 0.000 claims description 7
- 229920002554 vinyl polymer Polymers 0.000 claims description 7
- 229920006318 anionic polymer Polymers 0.000 claims description 4
- SCUZVMOVTVSBLE-UHFFFAOYSA-N prop-2-enenitrile;styrene Chemical compound C=CC#N.C=CC1=CC=CC=C1 SCUZVMOVTVSBLE-UHFFFAOYSA-N 0.000 claims description 4
- 229920000638 styrene acrylonitrile Polymers 0.000 claims description 4
- 125000004432 carbon atom Chemical group C* 0.000 claims description 3
- 239000006185 dispersion Substances 0.000 claims description 3
- 229920000178 Acrylic resin Polymers 0.000 claims 8
- 239000004925 Acrylic resin Substances 0.000 claims 8
- 239000004793 Polystyrene Substances 0.000 claims 4
- 239000002174 Styrene-butadiene Substances 0.000 claims 4
- MTAZNLWOLGHBHU-UHFFFAOYSA-N butadiene-styrene rubber Chemical compound C=CC=C.C=CC1=CC=CC=C1 MTAZNLWOLGHBHU-UHFFFAOYSA-N 0.000 claims 4
- 229920000098 polyolefin Polymers 0.000 claims 4
- 229920002223 polystyrene Polymers 0.000 claims 4
- 239000011115 styrene butadiene Substances 0.000 claims 4
- 229920003048 styrene butadiene rubber Polymers 0.000 claims 4
- 125000000391 vinyl group Chemical group [H]C([*])=C([H])[H] 0.000 claims 4
- XECAHXYUAAWDEL-UHFFFAOYSA-N acrylonitrile butadiene styrene Chemical compound C=CC=C.C=CC#N.C=CC1=CC=CC=C1 XECAHXYUAAWDEL-UHFFFAOYSA-N 0.000 claims 3
- 229920000122 acrylonitrile butadiene styrene Polymers 0.000 claims 3
- 239000004676 acrylonitrile butadiene styrene Substances 0.000 claims 3
- PIICEJLVQHRZGT-UHFFFAOYSA-N Ethylenediamine Chemical compound NCCN PIICEJLVQHRZGT-UHFFFAOYSA-N 0.000 claims 2
- 239000000835 fiber Substances 0.000 abstract description 37
- 239000000047 product Substances 0.000 abstract description 31
- 229940037003 alum Drugs 0.000 abstract description 11
- 239000007900 aqueous suspension Substances 0.000 abstract description 7
- 238000004519 manufacturing process Methods 0.000 abstract description 3
- 239000007859 condensation product Substances 0.000 abstract 1
- 235000010980 cellulose Nutrition 0.000 description 21
- 230000014759 maintenance of location Effects 0.000 description 15
- HEMHJVSKTPXQMS-UHFFFAOYSA-M Sodium hydroxide Chemical compound [OH-].[Na+] HEMHJVSKTPXQMS-UHFFFAOYSA-M 0.000 description 12
- XLYOFNOQVPJJNP-UHFFFAOYSA-N water Substances O XLYOFNOQVPJJNP-UHFFFAOYSA-N 0.000 description 12
- 238000012360 testing method Methods 0.000 description 8
- 239000003054 catalyst Substances 0.000 description 7
- 239000007787 solid Substances 0.000 description 7
- 238000013459 approach Methods 0.000 description 6
- 238000006243 chemical reaction Methods 0.000 description 6
- KRKNYBCHXYNGOX-UHFFFAOYSA-N citric acid Chemical compound OC(=O)CC(O)(C(O)=O)CC(O)=O KRKNYBCHXYNGOX-UHFFFAOYSA-N 0.000 description 6
- 239000000123 paper Substances 0.000 description 6
- 229920005989 resin Polymers 0.000 description 6
- 239000011347 resin Substances 0.000 description 6
- 229920013646 Hycar Polymers 0.000 description 5
- 230000008569 process Effects 0.000 description 4
- 239000004094 surface-active agent Substances 0.000 description 4
- KAKZBPTYRLMSJV-UHFFFAOYSA-N Butadiene Chemical compound C=CC=C KAKZBPTYRLMSJV-UHFFFAOYSA-N 0.000 description 3
- 239000004698 Polyethylene Substances 0.000 description 3
- PPBRXRYQALVLMV-UHFFFAOYSA-N Styrene Chemical compound C=CC1=CC=CC=C1 PPBRXRYQALVLMV-UHFFFAOYSA-N 0.000 description 3
- 238000013019 agitation Methods 0.000 description 3
- 230000008021 deposition Effects 0.000 description 3
- 150000004985 diamines Chemical class 0.000 description 3
- 238000001035 drying Methods 0.000 description 3
- 229920000573 polyethylene Polymers 0.000 description 3
- 239000000243 solution Substances 0.000 description 3
- 239000000725 suspension Substances 0.000 description 3
- HZAXFHJVJLSVMW-UHFFFAOYSA-N 2-Aminoethan-1-ol Chemical compound NCCO HZAXFHJVJLSVMW-UHFFFAOYSA-N 0.000 description 2
- IJGRMHOSHXDMSA-UHFFFAOYSA-N Atomic nitrogen Chemical compound N#N IJGRMHOSHXDMSA-UHFFFAOYSA-N 0.000 description 2
- 229920003182 Surlyn® Polymers 0.000 description 2
- 239000007864 aqueous solution Substances 0.000 description 2
- 230000015572 biosynthetic process Effects 0.000 description 2
- 238000004061 bleaching Methods 0.000 description 2
- 239000003795 chemical substances by application Substances 0.000 description 2
- 239000011248 coating agent Substances 0.000 description 2
- 238000000576 coating method Methods 0.000 description 2
- 150000002170 ethers Chemical class 0.000 description 2
- WQYVRQLZKVEZGA-UHFFFAOYSA-N hypochlorite Chemical compound Cl[O-] WQYVRQLZKVEZGA-UHFFFAOYSA-N 0.000 description 2
- 229910052757 nitrogen Inorganic materials 0.000 description 2
- 125000004433 nitrogen atom Chemical group N* 0.000 description 2
- 229920000058 polyacrylate Polymers 0.000 description 2
- 238000012545 processing Methods 0.000 description 2
- 230000000717 retained effect Effects 0.000 description 2
- 239000011734 sodium Substances 0.000 description 2
- 239000000126 substance Substances 0.000 description 2
- 238000009864 tensile test Methods 0.000 description 2
- 238000009736 wetting Methods 0.000 description 2
- 125000000022 2-aminoethyl group Chemical group [H]C([*])([H])C([H])([H])N([H])[H] 0.000 description 1
- SMNDYUVBFMFKNZ-UHFFFAOYSA-N 2-furoic acid Chemical compound OC(=O)C1=CC=CO1 SMNDYUVBFMFKNZ-UHFFFAOYSA-N 0.000 description 1
- QTBSBXVTEAMEQO-UHFFFAOYSA-M Acetate Chemical compound CC([O-])=O QTBSBXVTEAMEQO-UHFFFAOYSA-M 0.000 description 1
- 238000012935 Averaging Methods 0.000 description 1
- 101150039167 Bex3 gene Proteins 0.000 description 1
- RPNUMPOLZDHAAY-UHFFFAOYSA-N Diethylenetriamine Chemical compound NCCNCCN RPNUMPOLZDHAAY-UHFFFAOYSA-N 0.000 description 1
- 235000014466 Douglas bleu Nutrition 0.000 description 1
- 101100536354 Drosophila melanogaster tant gene Proteins 0.000 description 1
- VGGSQFUCUMXWEO-UHFFFAOYSA-N Ethene Chemical compound C=C VGGSQFUCUMXWEO-UHFFFAOYSA-N 0.000 description 1
- 239000005977 Ethylene Substances 0.000 description 1
- 241000282326 Felis catus Species 0.000 description 1
- 101001094537 Homo sapiens Retrotransposon Gag-like protein 3 Proteins 0.000 description 1
- DGAQECJNVWCQMB-PUAWFVPOSA-M Ilexoside XXIX Chemical compound C[C@@H]1CC[C@@]2(CC[C@@]3(C(=CC[C@H]4[C@]3(CC[C@@H]5[C@@]4(CC[C@@H](C5(C)C)OS(=O)(=O)[O-])C)C)[C@@H]2[C@]1(C)O)C)C(=O)O[C@H]6[C@@H]([C@H]([C@@H]([C@H](O6)CO)O)O)O.[Na+] DGAQECJNVWCQMB-PUAWFVPOSA-M 0.000 description 1
- 229920000877 Melamine resin Polymers 0.000 description 1
- CERQOIWHTDAKMF-UHFFFAOYSA-M Methacrylate Chemical compound CC(=C)C([O-])=O CERQOIWHTDAKMF-UHFFFAOYSA-M 0.000 description 1
- 239000004743 Polypropylene Substances 0.000 description 1
- ZTHYODDOHIVTJV-UHFFFAOYSA-N Propyl gallate Chemical compound CCCOC(=O)C1=CC(O)=C(O)C(O)=C1 ZTHYODDOHIVTJV-UHFFFAOYSA-N 0.000 description 1
- 240000001416 Pseudotsuga menziesii Species 0.000 description 1
- 235000005386 Pseudotsuga menziesii var menziesii Nutrition 0.000 description 1
- 229920001131 Pulp (paper) Polymers 0.000 description 1
- 102100035122 Retrotransposon Gag-like protein 3 Human genes 0.000 description 1
- KDYFGRWQOYBRFD-UHFFFAOYSA-N Succinic acid Natural products OC(=O)CCC(O)=O KDYFGRWQOYBRFD-UHFFFAOYSA-N 0.000 description 1
- BZHJMEDXRYGGRV-UHFFFAOYSA-N Vinyl chloride Chemical compound ClC=C BZHJMEDXRYGGRV-UHFFFAOYSA-N 0.000 description 1
- MZVQCMJNVPIDEA-UHFFFAOYSA-N [CH2]CN(CC)CC Chemical class [CH2]CN(CC)CC MZVQCMJNVPIDEA-UHFFFAOYSA-N 0.000 description 1
- 239000002250 absorbent Substances 0.000 description 1
- 230000002745 absorbent Effects 0.000 description 1
- 238000010521 absorption reaction Methods 0.000 description 1
- 238000007605 air drying Methods 0.000 description 1
- 239000004752 air-laid paper Substances 0.000 description 1
- 125000002947 alkylene group Chemical group 0.000 description 1
- 238000004458 analytical method Methods 0.000 description 1
- 125000004429 atom Chemical group 0.000 description 1
- 230000008901 benefit Effects 0.000 description 1
- 239000011230 binding agent Substances 0.000 description 1
- 239000007767 bonding agent Substances 0.000 description 1
- KDYFGRWQOYBRFD-NUQCWPJISA-N butanedioic acid Chemical compound O[14C](=O)CC[14C](O)=O KDYFGRWQOYBRFD-NUQCWPJISA-N 0.000 description 1
- 230000008859 change Effects 0.000 description 1
- 239000007795 chemical reaction product Substances 0.000 description 1
- 230000001143 conditioned effect Effects 0.000 description 1
- 238000010790 dilution Methods 0.000 description 1
- 239000012895 dilution Substances 0.000 description 1
- 238000007598 dipping method Methods 0.000 description 1
- 230000000694 effects Effects 0.000 description 1
- 230000001815 facial effect Effects 0.000 description 1
- 239000002657 fibrous material Substances 0.000 description 1
- 239000000945 filler Substances 0.000 description 1
- 238000007667 floating Methods 0.000 description 1
- 238000005187 foaming Methods 0.000 description 1
- 125000002887 hydroxy group Chemical group [H]O* 0.000 description 1
- 230000008676 import Effects 0.000 description 1
- 230000006872 improvement Effects 0.000 description 1
- INQOMBQAUSQDDS-UHFFFAOYSA-N iodomethane Chemical compound IC INQOMBQAUSQDDS-UHFFFAOYSA-N 0.000 description 1
- 150000002500 ions Chemical class 0.000 description 1
- 239000002655 kraft paper Substances 0.000 description 1
- JDSHMPZPIAZGSV-UHFFFAOYSA-N melamine Chemical compound NC1=NC(N)=NC(N)=N1 JDSHMPZPIAZGSV-UHFFFAOYSA-N 0.000 description 1
- 230000007935 neutral effect Effects 0.000 description 1
- 125000000449 nitro group Chemical group [O-][N+](*)=O 0.000 description 1
- 239000002245 particle Substances 0.000 description 1
- 238000011020 pilot scale process Methods 0.000 description 1
- 229920001083 polybutene Polymers 0.000 description 1
- 229920001155 polypropylene Polymers 0.000 description 1
- 238000003825 pressing Methods 0.000 description 1
- 239000013055 pulp slurry Substances 0.000 description 1
- 150000003254 radicals Chemical class 0.000 description 1
- GZUITABIAKMVPG-UHFFFAOYSA-N raloxifene Chemical compound C1=CC(O)=CC=C1C1=C(C(=O)C=2C=CC(OCCN3CCCCC3)=CC=2)C2=CC=C(O)C=C2S1 GZUITABIAKMVPG-UHFFFAOYSA-N 0.000 description 1
- 238000007127 saponification reaction Methods 0.000 description 1
- 239000002002 slurry Substances 0.000 description 1
- 229910052708 sodium Inorganic materials 0.000 description 1
- APSBXTVYXVQYAB-UHFFFAOYSA-M sodium docusate Chemical compound [Na+].CCCCC(CC)COC(=O)CC(S([O-])(=O)=O)C(=O)OCC(CC)CCCC APSBXTVYXVQYAB-UHFFFAOYSA-M 0.000 description 1
- MBEGFNBBAVRKLK-UHFFFAOYSA-N sodium;iminomethylideneazanide Chemical compound [Na+].[NH-]C#N MBEGFNBBAVRKLK-UHFFFAOYSA-N 0.000 description 1
- 241000894007 species Species 0.000 description 1
- 238000005507 spraying Methods 0.000 description 1
- 238000003756 stirring Methods 0.000 description 1
- 150000003512 tertiary amines Chemical class 0.000 description 1
- 238000010998 test method Methods 0.000 description 1
- 229920001169 thermoplastic Polymers 0.000 description 1
- 229920001187 thermosetting polymer Polymers 0.000 description 1
- 239000004416 thermosoftening plastic Substances 0.000 description 1
- PUVAFTRIIUSGLK-UHFFFAOYSA-M trimethyl(oxiran-2-ylmethyl)azanium;chloride Chemical compound [Cl-].C[N+](C)(C)CC1CO1 PUVAFTRIIUSGLK-UHFFFAOYSA-M 0.000 description 1
- GETQZCLCWQTVFV-UHFFFAOYSA-N trimethylamine Chemical class CN(C)C GETQZCLCWQTVFV-UHFFFAOYSA-N 0.000 description 1
- 238000005406 washing Methods 0.000 description 1
- 239000002023 wood Substances 0.000 description 1
Landscapes
- Paper (AREA)
Abstract
ABSTRACT OF THE DISCLOSURE
The invention is a fibrous cellulosic product, containing a uniformly dispersed polymeric material which has been deposited in an aqueous suspension from an anionic latex, and the method for its manufacture. Cellulosic fiber is first cationized by treating it in an aqueous suspension with the condensation product of epichlorohydrin and dimethylamine. Up to 30% of the dimethylamine may be replaced with a crosslinking agent which can be ammonia or an aliphatic diamine such as hexamethylene diamine. The cationized fiber, with or without small quantities of alum, will effectively retain a wide variety of anionic latices when treated in an aqueous environment.
The invention is a fibrous cellulosic product, containing a uniformly dispersed polymeric material which has been deposited in an aqueous suspension from an anionic latex, and the method for its manufacture. Cellulosic fiber is first cationized by treating it in an aqueous suspension with the condensation product of epichlorohydrin and dimethylamine. Up to 30% of the dimethylamine may be replaced with a crosslinking agent which can be ammonia or an aliphatic diamine such as hexamethylene diamine. The cationized fiber, with or without small quantities of alum, will effectively retain a wide variety of anionic latices when treated in an aqueous environment.
Description
~L2~
1251~ 1 LATEX TREATED CATIONIC CELI,ULOSE PRODUCT
AND METHOD FOR ITS PREPARATION
BACKGROUND OF THE INVENTION
The present invention is a fibrous eellulosic product containing a uniformly dispersed polymeric material wl~ch has been deposites~ in an aqueous suspension from an anionic latex. The invention further comprises the method of making the products. These products are especially advar~
5 tageous for making air laid webs wherein the polymer serves as a heat activatable bonding agent.
Treatmen$ of cellulosic products with polymers o~ various types has a long history in the p~p and papermaking art. Depending on the particular polymeric system being used, and the ultimate effect desired, this 10 treatment may take place either before or after formation of the sheet at the wet end of a paper machine. OFten it is desired to retain the polymer on or near the surface or surfaces of the sheet. In this case, it can be applied by any of the conventional coating technigues. For other applications, it is desirable for the polymer to be distributed uniformly throughout the sheet.
15 Where large amounts of polymer are desired, this can be accomplished by dipping or impregnating the sheet after the papermaking process. ~Iowever, where uniform distrib1~ion of smaller Mmolmts of polymer is desired, it is usually preferred to include the additive with the stock prior to the papermak ng process. Unfortunately, this is not always possible. Many 20 polymeric materials must be used in the form of aqueous emulsions. These emulsions are usually anionic in nature and, almost universally~ will have water as the continuous phase. Within the papermaking industry? these polymer emulsions are typically referred to as "latexes or latices." In the present application the term "Iatex" refers to very broadly to any anionic 25 aqueous emulsion of a polymeric material. These polymers can range from hard vitreous types to those which are soft and rubbery. They may be either thermoplastic or thermosetting in nature. In the case of therrnoplastic polymers they rnay ~e materials which remain permanently thermop~astic or they m~y be types which are partially or f~ly crosslinkable, with or withollt 3U an extern~l catnlyst, into therrnosetting types.
Because of their anionic nature, very few latices can be added directly to a pldp making slurry with the e~pectation of having satisfactory .~ ~
., , ; ~ .
.
retention. The cellulosic ~ibers are also anionic and they will repel the r esinparticles unless the fiber surface is modi-fied in some means to make it less negative in character. Cal:ionic retention aids are sometimes used to accomplish this purpose. Examples of this practice are fow~d in recent U.S.
PRtents to Jukes, et al., 4,125,645 and 4,256,807. A paper by Latimer and Gill, ~ 56(4): 66-69 (1973), describes the beater deposition of an acrylic latex onto wood pulp using a cationic deposition aid. Another approach ou~lined in Japnnese Kokai 85,374l74 has been to c~eate a cationic latex.
However, this approach is possible vvith only a very limited number of polymeric rnaterials.
The use of cationic retention or depos;tion ai~s is not without problems in its own right. Retention aids tend to be quite expensive and any given retention material may be totally ineffective with the latex of choice.
Rarely do retention efficiencies exceed 60-70~6. For these reasons, it has not been the usual practice to date to employ wet addition of latices except in very selective circurnstances.
Another approach has been to precipitate the polymer particles on the fibers by p~ change or by chemieal additives. Tl~is method can cause the latex to agglomerate and form relatively large globules rather than producing a ~iform fiber coating.
()ne problem with the use of retention aids has been the inability of the papermaker to precisely control the electrical charge of the fibers.
An approach that h~s received some study over the years has bsen to chemically modify the fiber surface to make it less negative. Uwatoko~
2S ~@~ (Japan~ 25(3): 360-362 (1974), briefly summarizes the state of art in regard to cationie fibers and lists six major approache~ thQt have been taken. The first method introduces side chains containing a tertiary nitrogen atom. These side chains are attached to the cellulose molecule at the hydroxyl groups as ethers. One product of this type which has received considerable study is the quaterr~zed diethylaminoethyl derivative OI
cellulose. A second route to the preparation of cationic cellulose is the reaction of cellu~ose in the presence of sodium hydroxide with ethanolamine?
aqueolJs ammonia, or melamine. A third process is the reaction between cellulose and a material such as 2-aminoethyl s~furic acid in the presence of sodium hydroxide. Another product has been formed by iminating an aminated cellulose by reaction between the aminated cellulose and ethylene ~ . , 3 .~
imlne. ~n approach which has received considerable st~ldy is the reaction of various trimethyl ammonium salts. Of particular import~nce has been glycidyl trimethyl ammonium chloride reacted with cel]ulose in the presence of a catalytie amount of sodium hydroxide. A related approach has been the reaction of 2-chloroethyldiethyl amune with aIkali eellulose. The product is then quaternized ~ith methyl iodide in anhydrous a]cohol. Finally, Uwa-toko comments on a process wnere cellulose is reacted with a solution of sodium acid cyanamide at a concentration of 50-200 g/L at a pH in the range of 10-13 and tel~erature of 10-40C for 4-24 hours.
McKelvey and senerito, J. Appl. Polymer Sci. 11:1693-1701 (1967), show the reaction of cellulose with a mi~ture of epichlorohydrin and a tertiary amine in the presence of aqueous sodium hydroxide.
The references cited are exemplary only since the preparation of cationic cellulose is not the subject of the present invention. The reader interested in a more detailed literature survey of cationie celluloses might refer to the present assigne~'s U.S. Patent No. 4,505,775. m is pat-ent, of whieh the present inventor is a eoinventor, deseribes a very inex-pensive and greatly simplified proeess for manufacturing a eationie eellu-lose. ~his is done by adding either a linear or partially crosslinked water soluble eondensate of epichlorohydrin and dimethylamine to an aqueous suspension of eellulose under alkaline conditions. The preferred coneen-trations of epichlorohydrin and dimethylamine will be approximately equi-molar in proportion. Amm~nia and primary aliphatie diamines serve to aet as eross-linking agents for the eondensates. Further, their use inereases the number of tertiary nitrogen atoms which may be quaternized to provide sites for positive eharges. Up to 30 molar percent of the dimethylamine may be replaeed by ammonia or the aliphatie diamine in the eondensation proeess. In general, it is preferred that the molar pereentage of the erosslinking material should be in the range of 10-20%. Preparation of suitable eondensates is deseribed in U.S. Patent No. 3,930,877 to Aitken.
It has been found that a eationie eellulose of the types deseribed in -the foregoing patent applieation can effeetively bond a wide variety of anionie latiees under the processing eonditions normally used prior to the wet end of a paper maehine. The products thus prepared have a wide v æiety of uses, partic~ æly in areas where the fibers are later formed into air laid we~hs of væ ious types.
t~, ",~j"~
, , '' "
. ;, ..
`~ p 5 1~514 SUMMARY OF THE INVENTIC~N
The present inventiorl comprises a new cornposition of matter and the method for making it. In its broadest form, the composition comprises a cat;onized cellulose and from 0.1-30%, on a dry weigh~ basis, of 5 a polymer capable of being emulsified into an anionic dispersion. The ca~ionized cellulose is an additive of cellulose with a material from the group consisting of a condensate of epichlorohydrin and dimetllylamine, said condensate further modified by a crosslinking agent, and mixtures thereof wherein the cross linking agent, if present, is selected from the group ln consisting of ammonia and a primary aliphatic diamine of the type H2N-R-NH2 llvherein E~ is an alkylene rad;cal of from 2 8 carbon atoms.
The product is made by first preparing the cationic cellulose by treating celll~ose under aqueous alkaline conditions with a material selected from the aforementioned group of condensates. The cationi~ed cellulose is 15 then treated in an aqueous suspension with an anionic polymer em~sion within the range of usage noted above. The cationic cellulose may be prepared aforehand and conventionally dried, as by sheeting, or it can be prepared, washed, and immediately treated with the appropriate latex. The term "latex" is considered in i$s broadest sense as being any aqueous based 20 anionic polymer emulsion in which ~ter is the continuous phase.
A preferred cationic additive is made using an approximately equimolar condensate of epic~orhy~rin and dimethylamine in which up to 30 molar percent of the dieth~lamine has been replaced by hexamethylene diamine. The cationizing condensate will normally be used in the range of 25 0.5-20 kg/t based on the dry weight of the cellulose. More typically it will be used within the range of 1-10 kgjt.
A wide range OI polymer emulsions or latices can be successfldly bonded to the cationic cell~ose. These can be polymers based on acryl~
nitrile9 styren~butadiene, styrene-acrylonitrile, acrylonitril~butadien~
30 styrene, acrylic and methacr~lic ethers, vinylacrylics, vinylaeetate~
vinylchloride, and p~lyolefins such as polyethylene, polypropylene~ and various polymers based on polybutene. Mixtures of two or more types of these polymers are considered to be within the scope of the invention as are block and graft copolymers of tWQ or more of the monomeric species just 35 noted. The abovs list should be considered as exernplary rather than limiting.
~Z~ 7 Among the preferred polymers are the various types broadly identified as polyvinyl acetate and polyacrylates and rnethacrylates.
Polyvinyl acetates are generally partially hydrolyzed materials and may be chemically modified so they can be crosslinked by applying heat, with or without the need for an external catalyst. l`he polyacrylate and methacrylate resins likewise are considered in a generic sense since there are many versions which may be either permanently thermsplastic or which can be crosslirlked with or without the need for an external calalyst. The resin treated products of the invention may be prepared in sheeted form, as loose fibrous materials, or in other of the forms well known in the papermaking industry. The products a~e particularly useful for making such absorbent materials as air laid paper towelling or indllstrial wipes. These products are currently made by spraying on as much as 30% latex binder after formation of an air laid feltO The large amount of water added at this time necessitates an adclitional drying step which is not required using the products of the present invention.
It is an object of the present invention to provide a fibrous, polyme~treated cellulosic product in which the polymer is uniformly distributed over the fiber surface.
It is another object to provide a simple method for adding a polymeric latex to cell~dosic fibers.
It is a further object to provide a method for treating cellulosic fibers in aqueous suspension with an anionic polymeric latex without the necessity ~or using a cationic retention or deposition aid.
These and many o~her objects will become immediately apparent to those skilled in the art upon reading the following detailed description.
DETA.ILED DESCRIPTION OF THE PREFERRED EM 3ODIMENTS
The products of the present invention are made by first preparing a cationic cellulose. This is made by treating a dilute aqueous suspension of the ce~lulose with a condensate of epichlorohydrin and dimethylamine (Epi-DMA) or a eondensate of these materials which has been modified by a crosslinking ~gent w}~ch may be ammonia or a primary aliphatic diamine of the type H2N-R-NH2 wherein R is an ~lkylene radical OI from 2-8 earbon atoms. This treatment may be carried out at the end of a bleaching sequence. Alternativ~ly, it can be carried out during any alkaline bleaching step at which the pH is 10 or above, as long as this step is ., , p 5 not followed by a c~orin~tion or hypochlorite stage. The temperature and ffme for the preparation of the catiorlic cellulose are not criticHl. The addition and/or reaction product be$ween celludose and the Epi-DMA
condenstate appears to form very rapidly. The cationized cellulose product 5 may then be dried by convention~l sheeting, as loose fiber, or in other physical forms. It may be also used without further drying wherein it is suspended in w ater and the appropriate latex simply added 7vith gentle agitation.
The following examples will serve to show specific embodiments 10 of the present invention.
Example 1 Bleached Douglas-fir kraft pulp was obtained from a northwestern pulp mill. Samples having 15.5 g of dry fiber wele slurried in 760 mL of water to produce a suspension having 2% consistency. The pH
was adjusted to 1û.5 with Na~H and 0.16 g of a 50% aqueous solution (5 kg/t on an active materi~l basis~ of an epichlorohydri~dimethylamine condensate partially crosslinked with hexamethylene diamine was added with stirring.
The condensate is av~ilable as Nalco ~-7135 frorn Nalco Chemic~l Co., Oak Brook, ~linois. Aîter gen'de agitation for 30 minutes the pulp was drained on a Buelmer funnel and washed lmtil the washings were essentially neutral.
This cationic product was stor d for furthe~ use without drying~ Kil~da~il nitrogen determinations made on the treated product showed a retention efficiency for the additive in the range ~ 85-90%. The procedure was readily sc~led up for preparation of larger quantities of c~tionic fiber without any loss of retention efficiency.
Exam~
C~tionic fiber prepared as in Ex~mple 1 was reslurried in water to give a suspension at 2% eonsistency. Using continuous gentle egitation, varying arnounts of a crosslinkable polyvinyl acetate em~sion having 50%
solids content were added. Samples were made using 5, 10, and 30%
emulsion solids based on cationized fiber. One suitable emulsion is available as Airflex 105 from hir Products and Chemicals, Inc., Allentown, Pennsylvania. Agitation was continued for 30 seconds after completion of latex addi Ition. Additional dilution water was added and the fi~er suspension was formed into hand sheets in ~ standard 8 x 8 inch (20.3 x 20.3 ~m) Noble and Wood laboratory sheet former. The sheets were drum dried to about k Trade Mark '~' '- '' ,, , ",~
~LZ~ 37 80% moisture and then conditioned. Standard Mullen burst tests were run on the sheets after air drying and before further processing.
After checking burst values, the sheets were refiberiæed dry in a high shear blender and air felted into sheets 6 inches (15.9 cm) in diameter 5 with a basis weight averaging 50 g/m2. The air ormed felts were pressed for 15 seconds at 150C and 300 psi (2,068 kPa) to consolidate the~n into handleable tissue sheets.
An additional sample was made using 1û% of the polyvinyl acetate latex. A~ter the dry felted sheets were formed, but before pressing, 10 one sample set was sprayed with a water solution containing 0.74%, based on latex solidsJ of citric acid. Citric acid serves as a catalyst to induce crosslinking of the polymer.
Dry tensile strength values were determined for the tissues using a constant rate of elongation tester having a head speed of 2 in./min. with R
15 3 in. span between clamps and 1 in. wide samples. Test results are shown in the following table.
Table I
Resin U~e2 %~Iandsheet M~len, kPa 8 0 90~1100 ~-10 112~ 18 lû 150~ 45 10 ~ catalyst 1530 88 The dramatic improvement in dry laid tissue tensile strength 30 using up to 1û% latex is immediately apparent.
Products made a¢cording to the p~esent invention have potential applications in many areas. Among these are uses where strength must be combined with so~tness to the touch. Paper towe3ing and facial tissues are 35 ex~mples as are wrapper tissues for diaper and sanitary napkin fillers. In many of these uses rapid water absorption is also important.
Latex treated samples were made as in Example 2, using 10%
latex solids based on cationized pulp. In addition to the polyYinyl acetate latex used previously, a sample set was made using Airflex 4500 polyvinyl 40 c~oride crosslinking latex. This is available from the supplier noted previously.
1~514 8 One sarnple with ea~h latex was further treated with surfactant to promote rapid wetting. Th;s was added as an aqueous solution at the time of lAtex addition to the cationized pulp slurry, using 0.74% based on latex solids. Many types of surfflctants are suitable. The specific S rnaterial used for the products in this example was Aerosol OT, a dioct~l ester of sodium s~f~succinic acid, available from Amer;can Cyanamid Co.
Wayne, New Jersey.
The produc~s were made into dry laid sheets a~ before with the exception that basis weight WAS increased to an average of 200 g/m2 to 1a simulate pQper toweling. On selected samples a citric ~cid catalyst solution was sprayed on the air felted fiber~ ~s described in Example 2, to promote crosslinking of the resin. An amount equivalent to 0.74% based on latex solids was used.
Wet and dry tensile strengths were determined as was the time 15 to completely wet out a 5.1 x 501 cm sampls free floating on a water surfaee. In order to avoid handling damage to strip6 intended for wet tensile tests, the strips were placed dry in the jaws oE the tester an~ then water sprayed until thoroug}~y wet. Results of the tests follow, TABLE ~
Resin Wetting Agellt Tersile Strength9 N/m WettingTime, :E mldsion Present ~ Wet sec.
PVAc A-105(1) No - - 52 P~Ac ~ Cat~l~st No 251 38. 7 34 PVAc + Catalyst Yes 283 39. 3 1. 6 30 PV~ A-45oo(2j No - - 3. 2 PVC + Cat~lyst No 112 .36. 3 3 . 2 PVC ~ Cat~lyst Yes 81 32~0 1.4 None No ~10 - 0. ~1.0 (1) Polyvinyl acetate
1251~ 1 LATEX TREATED CATIONIC CELI,ULOSE PRODUCT
AND METHOD FOR ITS PREPARATION
BACKGROUND OF THE INVENTION
The present invention is a fibrous eellulosic product containing a uniformly dispersed polymeric material wl~ch has been deposites~ in an aqueous suspension from an anionic latex. The invention further comprises the method of making the products. These products are especially advar~
5 tageous for making air laid webs wherein the polymer serves as a heat activatable bonding agent.
Treatmen$ of cellulosic products with polymers o~ various types has a long history in the p~p and papermaking art. Depending on the particular polymeric system being used, and the ultimate effect desired, this 10 treatment may take place either before or after formation of the sheet at the wet end of a paper machine. OFten it is desired to retain the polymer on or near the surface or surfaces of the sheet. In this case, it can be applied by any of the conventional coating technigues. For other applications, it is desirable for the polymer to be distributed uniformly throughout the sheet.
15 Where large amounts of polymer are desired, this can be accomplished by dipping or impregnating the sheet after the papermaking process. ~Iowever, where uniform distrib1~ion of smaller Mmolmts of polymer is desired, it is usually preferred to include the additive with the stock prior to the papermak ng process. Unfortunately, this is not always possible. Many 20 polymeric materials must be used in the form of aqueous emulsions. These emulsions are usually anionic in nature and, almost universally~ will have water as the continuous phase. Within the papermaking industry? these polymer emulsions are typically referred to as "latexes or latices." In the present application the term "Iatex" refers to very broadly to any anionic 25 aqueous emulsion of a polymeric material. These polymers can range from hard vitreous types to those which are soft and rubbery. They may be either thermoplastic or thermosetting in nature. In the case of therrnoplastic polymers they rnay ~e materials which remain permanently thermop~astic or they m~y be types which are partially or f~ly crosslinkable, with or withollt 3U an extern~l catnlyst, into therrnosetting types.
Because of their anionic nature, very few latices can be added directly to a pldp making slurry with the e~pectation of having satisfactory .~ ~
., , ; ~ .
.
retention. The cellulosic ~ibers are also anionic and they will repel the r esinparticles unless the fiber surface is modi-fied in some means to make it less negative in character. Cal:ionic retention aids are sometimes used to accomplish this purpose. Examples of this practice are fow~d in recent U.S.
PRtents to Jukes, et al., 4,125,645 and 4,256,807. A paper by Latimer and Gill, ~ 56(4): 66-69 (1973), describes the beater deposition of an acrylic latex onto wood pulp using a cationic deposition aid. Another approach ou~lined in Japnnese Kokai 85,374l74 has been to c~eate a cationic latex.
However, this approach is possible vvith only a very limited number of polymeric rnaterials.
The use of cationic retention or depos;tion ai~s is not without problems in its own right. Retention aids tend to be quite expensive and any given retention material may be totally ineffective with the latex of choice.
Rarely do retention efficiencies exceed 60-70~6. For these reasons, it has not been the usual practice to date to employ wet addition of latices except in very selective circurnstances.
Another approach has been to precipitate the polymer particles on the fibers by p~ change or by chemieal additives. Tl~is method can cause the latex to agglomerate and form relatively large globules rather than producing a ~iform fiber coating.
()ne problem with the use of retention aids has been the inability of the papermaker to precisely control the electrical charge of the fibers.
An approach that h~s received some study over the years has bsen to chemically modify the fiber surface to make it less negative. Uwatoko~
2S ~@~ (Japan~ 25(3): 360-362 (1974), briefly summarizes the state of art in regard to cationie fibers and lists six major approache~ thQt have been taken. The first method introduces side chains containing a tertiary nitrogen atom. These side chains are attached to the cellulose molecule at the hydroxyl groups as ethers. One product of this type which has received considerable study is the quaterr~zed diethylaminoethyl derivative OI
cellulose. A second route to the preparation of cationic cellulose is the reaction of cellu~ose in the presence of sodium hydroxide with ethanolamine?
aqueolJs ammonia, or melamine. A third process is the reaction between cellulose and a material such as 2-aminoethyl s~furic acid in the presence of sodium hydroxide. Another product has been formed by iminating an aminated cellulose by reaction between the aminated cellulose and ethylene ~ . , 3 .~
imlne. ~n approach which has received considerable st~ldy is the reaction of various trimethyl ammonium salts. Of particular import~nce has been glycidyl trimethyl ammonium chloride reacted with cel]ulose in the presence of a catalytie amount of sodium hydroxide. A related approach has been the reaction of 2-chloroethyldiethyl amune with aIkali eellulose. The product is then quaternized ~ith methyl iodide in anhydrous a]cohol. Finally, Uwa-toko comments on a process wnere cellulose is reacted with a solution of sodium acid cyanamide at a concentration of 50-200 g/L at a pH in the range of 10-13 and tel~erature of 10-40C for 4-24 hours.
McKelvey and senerito, J. Appl. Polymer Sci. 11:1693-1701 (1967), show the reaction of cellulose with a mi~ture of epichlorohydrin and a tertiary amine in the presence of aqueous sodium hydroxide.
The references cited are exemplary only since the preparation of cationic cellulose is not the subject of the present invention. The reader interested in a more detailed literature survey of cationie celluloses might refer to the present assigne~'s U.S. Patent No. 4,505,775. m is pat-ent, of whieh the present inventor is a eoinventor, deseribes a very inex-pensive and greatly simplified proeess for manufacturing a eationie eellu-lose. ~his is done by adding either a linear or partially crosslinked water soluble eondensate of epichlorohydrin and dimethylamine to an aqueous suspension of eellulose under alkaline conditions. The preferred coneen-trations of epichlorohydrin and dimethylamine will be approximately equi-molar in proportion. Amm~nia and primary aliphatie diamines serve to aet as eross-linking agents for the eondensates. Further, their use inereases the number of tertiary nitrogen atoms which may be quaternized to provide sites for positive eharges. Up to 30 molar percent of the dimethylamine may be replaeed by ammonia or the aliphatie diamine in the eondensation proeess. In general, it is preferred that the molar pereentage of the erosslinking material should be in the range of 10-20%. Preparation of suitable eondensates is deseribed in U.S. Patent No. 3,930,877 to Aitken.
It has been found that a eationie eellulose of the types deseribed in -the foregoing patent applieation can effeetively bond a wide variety of anionie latiees under the processing eonditions normally used prior to the wet end of a paper maehine. The products thus prepared have a wide v æiety of uses, partic~ æly in areas where the fibers are later formed into air laid we~hs of væ ious types.
t~, ",~j"~
, , '' "
. ;, ..
`~ p 5 1~514 SUMMARY OF THE INVENTIC~N
The present inventiorl comprises a new cornposition of matter and the method for making it. In its broadest form, the composition comprises a cat;onized cellulose and from 0.1-30%, on a dry weigh~ basis, of 5 a polymer capable of being emulsified into an anionic dispersion. The ca~ionized cellulose is an additive of cellulose with a material from the group consisting of a condensate of epichlorohydrin and dimetllylamine, said condensate further modified by a crosslinking agent, and mixtures thereof wherein the cross linking agent, if present, is selected from the group ln consisting of ammonia and a primary aliphatic diamine of the type H2N-R-NH2 llvherein E~ is an alkylene rad;cal of from 2 8 carbon atoms.
The product is made by first preparing the cationic cellulose by treating celll~ose under aqueous alkaline conditions with a material selected from the aforementioned group of condensates. The cationi~ed cellulose is 15 then treated in an aqueous suspension with an anionic polymer em~sion within the range of usage noted above. The cationic cellulose may be prepared aforehand and conventionally dried, as by sheeting, or it can be prepared, washed, and immediately treated with the appropriate latex. The term "latex" is considered in i$s broadest sense as being any aqueous based 20 anionic polymer emulsion in which ~ter is the continuous phase.
A preferred cationic additive is made using an approximately equimolar condensate of epic~orhy~rin and dimethylamine in which up to 30 molar percent of the dieth~lamine has been replaced by hexamethylene diamine. The cationizing condensate will normally be used in the range of 25 0.5-20 kg/t based on the dry weight of the cellulose. More typically it will be used within the range of 1-10 kgjt.
A wide range OI polymer emulsions or latices can be successfldly bonded to the cationic cell~ose. These can be polymers based on acryl~
nitrile9 styren~butadiene, styrene-acrylonitrile, acrylonitril~butadien~
30 styrene, acrylic and methacr~lic ethers, vinylacrylics, vinylaeetate~
vinylchloride, and p~lyolefins such as polyethylene, polypropylene~ and various polymers based on polybutene. Mixtures of two or more types of these polymers are considered to be within the scope of the invention as are block and graft copolymers of tWQ or more of the monomeric species just 35 noted. The abovs list should be considered as exernplary rather than limiting.
~Z~ 7 Among the preferred polymers are the various types broadly identified as polyvinyl acetate and polyacrylates and rnethacrylates.
Polyvinyl acetates are generally partially hydrolyzed materials and may be chemically modified so they can be crosslinked by applying heat, with or without the need for an external catalyst. l`he polyacrylate and methacrylate resins likewise are considered in a generic sense since there are many versions which may be either permanently thermsplastic or which can be crosslirlked with or without the need for an external calalyst. The resin treated products of the invention may be prepared in sheeted form, as loose fibrous materials, or in other of the forms well known in the papermaking industry. The products a~e particularly useful for making such absorbent materials as air laid paper towelling or indllstrial wipes. These products are currently made by spraying on as much as 30% latex binder after formation of an air laid feltO The large amount of water added at this time necessitates an adclitional drying step which is not required using the products of the present invention.
It is an object of the present invention to provide a fibrous, polyme~treated cellulosic product in which the polymer is uniformly distributed over the fiber surface.
It is another object to provide a simple method for adding a polymeric latex to cell~dosic fibers.
It is a further object to provide a method for treating cellulosic fibers in aqueous suspension with an anionic polymeric latex without the necessity ~or using a cationic retention or deposition aid.
These and many o~her objects will become immediately apparent to those skilled in the art upon reading the following detailed description.
DETA.ILED DESCRIPTION OF THE PREFERRED EM 3ODIMENTS
The products of the present invention are made by first preparing a cationic cellulose. This is made by treating a dilute aqueous suspension of the ce~lulose with a condensate of epichlorohydrin and dimethylamine (Epi-DMA) or a eondensate of these materials which has been modified by a crosslinking ~gent w}~ch may be ammonia or a primary aliphatic diamine of the type H2N-R-NH2 wherein R is an ~lkylene radical OI from 2-8 earbon atoms. This treatment may be carried out at the end of a bleaching sequence. Alternativ~ly, it can be carried out during any alkaline bleaching step at which the pH is 10 or above, as long as this step is ., , p 5 not followed by a c~orin~tion or hypochlorite stage. The temperature and ffme for the preparation of the catiorlic cellulose are not criticHl. The addition and/or reaction product be$ween celludose and the Epi-DMA
condenstate appears to form very rapidly. The cationized cellulose product 5 may then be dried by convention~l sheeting, as loose fiber, or in other physical forms. It may be also used without further drying wherein it is suspended in w ater and the appropriate latex simply added 7vith gentle agitation.
The following examples will serve to show specific embodiments 10 of the present invention.
Example 1 Bleached Douglas-fir kraft pulp was obtained from a northwestern pulp mill. Samples having 15.5 g of dry fiber wele slurried in 760 mL of water to produce a suspension having 2% consistency. The pH
was adjusted to 1û.5 with Na~H and 0.16 g of a 50% aqueous solution (5 kg/t on an active materi~l basis~ of an epichlorohydri~dimethylamine condensate partially crosslinked with hexamethylene diamine was added with stirring.
The condensate is av~ilable as Nalco ~-7135 frorn Nalco Chemic~l Co., Oak Brook, ~linois. Aîter gen'de agitation for 30 minutes the pulp was drained on a Buelmer funnel and washed lmtil the washings were essentially neutral.
This cationic product was stor d for furthe~ use without drying~ Kil~da~il nitrogen determinations made on the treated product showed a retention efficiency for the additive in the range ~ 85-90%. The procedure was readily sc~led up for preparation of larger quantities of c~tionic fiber without any loss of retention efficiency.
Exam~
C~tionic fiber prepared as in Ex~mple 1 was reslurried in water to give a suspension at 2% eonsistency. Using continuous gentle egitation, varying arnounts of a crosslinkable polyvinyl acetate em~sion having 50%
solids content were added. Samples were made using 5, 10, and 30%
emulsion solids based on cationized fiber. One suitable emulsion is available as Airflex 105 from hir Products and Chemicals, Inc., Allentown, Pennsylvania. Agitation was continued for 30 seconds after completion of latex addi Ition. Additional dilution water was added and the fi~er suspension was formed into hand sheets in ~ standard 8 x 8 inch (20.3 x 20.3 ~m) Noble and Wood laboratory sheet former. The sheets were drum dried to about k Trade Mark '~' '- '' ,, , ",~
~LZ~ 37 80% moisture and then conditioned. Standard Mullen burst tests were run on the sheets after air drying and before further processing.
After checking burst values, the sheets were refiberiæed dry in a high shear blender and air felted into sheets 6 inches (15.9 cm) in diameter 5 with a basis weight averaging 50 g/m2. The air ormed felts were pressed for 15 seconds at 150C and 300 psi (2,068 kPa) to consolidate the~n into handleable tissue sheets.
An additional sample was made using 1û% of the polyvinyl acetate latex. A~ter the dry felted sheets were formed, but before pressing, 10 one sample set was sprayed with a water solution containing 0.74%, based on latex solidsJ of citric acid. Citric acid serves as a catalyst to induce crosslinking of the polymer.
Dry tensile strength values were determined for the tissues using a constant rate of elongation tester having a head speed of 2 in./min. with R
15 3 in. span between clamps and 1 in. wide samples. Test results are shown in the following table.
Table I
Resin U~e2 %~Iandsheet M~len, kPa 8 0 90~1100 ~-10 112~ 18 lû 150~ 45 10 ~ catalyst 1530 88 The dramatic improvement in dry laid tissue tensile strength 30 using up to 1û% latex is immediately apparent.
Products made a¢cording to the p~esent invention have potential applications in many areas. Among these are uses where strength must be combined with so~tness to the touch. Paper towe3ing and facial tissues are 35 ex~mples as are wrapper tissues for diaper and sanitary napkin fillers. In many of these uses rapid water absorption is also important.
Latex treated samples were made as in Example 2, using 10%
latex solids based on cationized pulp. In addition to the polyYinyl acetate latex used previously, a sample set was made using Airflex 4500 polyvinyl 40 c~oride crosslinking latex. This is available from the supplier noted previously.
1~514 8 One sarnple with ea~h latex was further treated with surfactant to promote rapid wetting. Th;s was added as an aqueous solution at the time of lAtex addition to the cationized pulp slurry, using 0.74% based on latex solids. Many types of surfflctants are suitable. The specific S rnaterial used for the products in this example was Aerosol OT, a dioct~l ester of sodium s~f~succinic acid, available from Amer;can Cyanamid Co.
Wayne, New Jersey.
The produc~s were made into dry laid sheets a~ before with the exception that basis weight WAS increased to an average of 200 g/m2 to 1a simulate pQper toweling. On selected samples a citric ~cid catalyst solution was sprayed on the air felted fiber~ ~s described in Example 2, to promote crosslinking of the resin. An amount equivalent to 0.74% based on latex solids was used.
Wet and dry tensile strengths were determined as was the time 15 to completely wet out a 5.1 x 501 cm sampls free floating on a water surfaee. In order to avoid handling damage to strip6 intended for wet tensile tests, the strips were placed dry in the jaws oE the tester an~ then water sprayed until thoroug}~y wet. Results of the tests follow, TABLE ~
Resin Wetting Agellt Tersile Strength9 N/m WettingTime, :E mldsion Present ~ Wet sec.
PVAc A-105(1) No - - 52 P~Ac ~ Cat~l~st No 251 38. 7 34 PVAc + Catalyst Yes 283 39. 3 1. 6 30 PV~ A-45oo(2j No - - 3. 2 PVC + Cat~lyst No 112 .36. 3 3 . 2 PVC ~ Cat~lyst Yes 81 32~0 1.4 None No ~10 - 0. ~1.0 (1) Polyvinyl acetate
(2) Polyvinyl cl~oride The effectiYeness of the surfactant in reducing wetting time is 40 immediat~ly apparent. This may in part be due to the cationic nature of the fiber which serv~ to retain the anior~ic surfa~tant.
After the above labor~tory tests had been complete, trials were .~ ~ made on a continuous pilot scale paper machine using cataonized fiber as the ',J ,:; .
* 'rrade Mar3~
cellulosic furnish. In the first trial, the resin emulsion was added to the fiber at the machine chest. This is an area of vigorous agitat;on which caused foaming, resulting in numerous sheet breaks. In a later trial, the latex was added just prior to the headbox. Running conditions on the paper 5 machine and product quality were excellent.
The optimum point for adding the surfactant in a paper machine run has not yet been determined. Adding the surfactant following latex addition and immediately prior to the machine headbox failed to achieve results equal to those reached in laboratory trialsO
A set of samples si:nilar to those described earlier in the example was made using uneationized fiber. Latex usage was 10% solids based on dry fiber. Son some samples 10 kg/t of alum was used at the time of latex addition.
Table III
Resin Catalyst AlumI:)ry Tensile Emulsion Present Present_trength, N/m ___ __._ 20 PYAc A-105 No No 37 PVAc A-105 No Yes 83 PVAc A-105 Yes No 50 PVAc A-180 No No 52 PVAcA-180 No Yes 111 25 PVAc A-180 Yes No 50 PVC A-450U No No 56 PVC A-4500 No Yes 144 The tensile strength superiority of the samples .nade with 30 cationized fiber is immediately evident with the exeeption of the one sample made with PVC and alum.
Example 4 The cationized fiber of Example 1 is effective in retaining a wide variety of anionic polymer dispersions (latices) having significantly 35 differing ehemical properties. As might be expected, ~his array of latices produces Idtimate products which may differ significantly in physical and chemical properties. However, most of the resin systems testecl produced a very significant increase in the tensile strength of a dry felted tissue product, made as described in ~xample 2. Tests were made with the 40 following polymer emulsions: Airflex 105 and 120 ~polyvinyl acetate), Airflex 4500 (polyvinyl chloride, all available from Air Products and P 5 ~Z'~ 7 Chemicels Co., Allentown, Pennsylvani~ Hycar 267:L and 26170 (acrylic) and Hycar 1572 and 1572X64 (acrylonitrile), all products of B.F. Goodrich Company, Cleveland, Ohio; and Surlyn 56220 (polyethylene) available from E.l. duPont de Nemours ~ Co.~ Wilmington, Delaware~ Each was added as 5 described in Example 2 using 10% polymer solids ~sed on cationized fiber.
The following tensile tests were run on air laid tissues having a 50 glm2 basis weight. No catalyst was llsed for any samples.
Table IV
Tensile Strength Polymer Emulsion Resin T~ N/m Airflex 105 Polyvinyl acetate 4S
Airflex 120 Polyvinyl acetate 19 Airflex 4500 Polyvinyl cldoride45 Hycar 4671 Acrylic 38 Hycar 26170 Acrylic 26 Elycar 1572 Acrylonitrile 22 ~0 Hycar 1572X64 Acrylonitrile 20 Surlyn 56220 Polyethylene 10 None 6-10 The irnprovement i~ tensile strengths over an untreated control 25 is immediately apparent.
The above tests are not shown as a comparison of the rEilative me~its ~f the products tested. Ma~y p~operties besides dry tensile strength are irnportant ~nd these will vary greatly between different resin types.
Further, it is ur~ikely that all, or even any, were slsed under opffmum 30 conditions~ Nor are the tests to be regarded as any endorsement of the products of the a~ve manufacturers since many competing products are considered to work equally well. rrhe purpose of the tests was solely to show the effectiveness of the cationized Iiber at retair~ing various generic types OI latlces without the need ~or external retention aidsO
Analytical methods are not available for precise determination of the amounts of dif~erent types of latices retained by cationized fiber. By using a saponification method, it is estimated that about 82% of the A~105 polyvinyl acetate is re~ained. Other test methods indicate retention of various latex types in the range of. 60 ~o 90~9~. The use of small quantities 40 of alum; e.g., 2.5 -10 kg/t with the cationi~ed fiber can improYe retention of some types of latex as is shown in the following examples.
,, ,~ , ~rl; * Trade ~hrk ~L~ 7 1~514 11 ~'~
A cationic cellulose is made as in Example 1 except that an uncrosslinked epic~orohydrin~dimethylamine condensate (Nalco N-7655) (Epi-DMA) was used in place OI the hexameth~lene diamine (HMDA~
5 modified material of the previous example. Usage in the present case was higher, 10 kg/t, in contrast to 5 kg/t for the earlier material. Retention efficiency of the condensate was measured by Kjeldal~ nitro~en determina-tion as about 87%.
The cationized fibers of ~xamples 1 and 5 were slurried in water and varying amounts of a self-crosslinking acrylic emulsion latex (UCAR
872, Union Carbide Corp., New York, New York) were added. Handsheets were then made from the fiber latex mixtures. In addition to the two treated materials, trials were run on untreated pulp and untreated pulp with 15 alum in ranges from 2.5 to 5 kg/t alum.
Untreated fiber, untreated fiber with alum and the fiber treated with 10 kg/t 13pi-DMA were inefEective at retaining this latex, which was essentially all lost with the white water. Fiber treated with HMDA
modified condensate showed exeellent latex retention7 as measured by 20 increase in sheet weight.
When small amounts OI alum were added to the mixture of Epi-DMA treated fiber and latex, the latex was effectively retained at alum usages of 5 k~/t and greater. Alum at usages of about 2.5 kg/t also improved latex retention of fiber treated with HMDA modified polymer 25 although not to the same extent as with the Epi-DMA treated fib~r. With the HMDA modified sample, there did not appear to be significant advantage in using alum in amounts greater than 2.5 kg/t.
It is apparent that the partic~ar cationi~ing agent used will affect the finul fiber properties. Some age~ts will be optimum for certain 30 latices but will be less effective with others. There does not appear to be any way to predict this relationship and it must, to a large degree, be determined experimentally.
It will be eviden~ to those skilled in the art that many variations can be made without departing from the spirit of the present invention. The
After the above labor~tory tests had been complete, trials were .~ ~ made on a continuous pilot scale paper machine using cataonized fiber as the ',J ,:; .
* 'rrade Mar3~
cellulosic furnish. In the first trial, the resin emulsion was added to the fiber at the machine chest. This is an area of vigorous agitat;on which caused foaming, resulting in numerous sheet breaks. In a later trial, the latex was added just prior to the headbox. Running conditions on the paper 5 machine and product quality were excellent.
The optimum point for adding the surfactant in a paper machine run has not yet been determined. Adding the surfactant following latex addition and immediately prior to the machine headbox failed to achieve results equal to those reached in laboratory trialsO
A set of samples si:nilar to those described earlier in the example was made using uneationized fiber. Latex usage was 10% solids based on dry fiber. Son some samples 10 kg/t of alum was used at the time of latex addition.
Table III
Resin Catalyst AlumI:)ry Tensile Emulsion Present Present_trength, N/m ___ __._ 20 PYAc A-105 No No 37 PVAc A-105 No Yes 83 PVAc A-105 Yes No 50 PVAc A-180 No No 52 PVAcA-180 No Yes 111 25 PVAc A-180 Yes No 50 PVC A-450U No No 56 PVC A-4500 No Yes 144 The tensile strength superiority of the samples .nade with 30 cationized fiber is immediately evident with the exeeption of the one sample made with PVC and alum.
Example 4 The cationized fiber of Example 1 is effective in retaining a wide variety of anionic polymer dispersions (latices) having significantly 35 differing ehemical properties. As might be expected, ~his array of latices produces Idtimate products which may differ significantly in physical and chemical properties. However, most of the resin systems testecl produced a very significant increase in the tensile strength of a dry felted tissue product, made as described in ~xample 2. Tests were made with the 40 following polymer emulsions: Airflex 105 and 120 ~polyvinyl acetate), Airflex 4500 (polyvinyl chloride, all available from Air Products and P 5 ~Z'~ 7 Chemicels Co., Allentown, Pennsylvani~ Hycar 267:L and 26170 (acrylic) and Hycar 1572 and 1572X64 (acrylonitrile), all products of B.F. Goodrich Company, Cleveland, Ohio; and Surlyn 56220 (polyethylene) available from E.l. duPont de Nemours ~ Co.~ Wilmington, Delaware~ Each was added as 5 described in Example 2 using 10% polymer solids ~sed on cationized fiber.
The following tensile tests were run on air laid tissues having a 50 glm2 basis weight. No catalyst was llsed for any samples.
Table IV
Tensile Strength Polymer Emulsion Resin T~ N/m Airflex 105 Polyvinyl acetate 4S
Airflex 120 Polyvinyl acetate 19 Airflex 4500 Polyvinyl cldoride45 Hycar 4671 Acrylic 38 Hycar 26170 Acrylic 26 Elycar 1572 Acrylonitrile 22 ~0 Hycar 1572X64 Acrylonitrile 20 Surlyn 56220 Polyethylene 10 None 6-10 The irnprovement i~ tensile strengths over an untreated control 25 is immediately apparent.
The above tests are not shown as a comparison of the rEilative me~its ~f the products tested. Ma~y p~operties besides dry tensile strength are irnportant ~nd these will vary greatly between different resin types.
Further, it is ur~ikely that all, or even any, were slsed under opffmum 30 conditions~ Nor are the tests to be regarded as any endorsement of the products of the a~ve manufacturers since many competing products are considered to work equally well. rrhe purpose of the tests was solely to show the effectiveness of the cationized Iiber at retair~ing various generic types OI latlces without the need ~or external retention aidsO
Analytical methods are not available for precise determination of the amounts of dif~erent types of latices retained by cationized fiber. By using a saponification method, it is estimated that about 82% of the A~105 polyvinyl acetate is re~ained. Other test methods indicate retention of various latex types in the range of. 60 ~o 90~9~. The use of small quantities 40 of alum; e.g., 2.5 -10 kg/t with the cationi~ed fiber can improYe retention of some types of latex as is shown in the following examples.
,, ,~ , ~rl; * Trade ~hrk ~L~ 7 1~514 11 ~'~
A cationic cellulose is made as in Example 1 except that an uncrosslinked epic~orohydrin~dimethylamine condensate (Nalco N-7655) (Epi-DMA) was used in place OI the hexameth~lene diamine (HMDA~
5 modified material of the previous example. Usage in the present case was higher, 10 kg/t, in contrast to 5 kg/t for the earlier material. Retention efficiency of the condensate was measured by Kjeldal~ nitro~en determina-tion as about 87%.
The cationized fibers of ~xamples 1 and 5 were slurried in water and varying amounts of a self-crosslinking acrylic emulsion latex (UCAR
872, Union Carbide Corp., New York, New York) were added. Handsheets were then made from the fiber latex mixtures. In addition to the two treated materials, trials were run on untreated pulp and untreated pulp with 15 alum in ranges from 2.5 to 5 kg/t alum.
Untreated fiber, untreated fiber with alum and the fiber treated with 10 kg/t 13pi-DMA were inefEective at retaining this latex, which was essentially all lost with the white water. Fiber treated with HMDA
modified condensate showed exeellent latex retention7 as measured by 20 increase in sheet weight.
When small amounts OI alum were added to the mixture of Epi-DMA treated fiber and latex, the latex was effectively retained at alum usages of 5 k~/t and greater. Alum at usages of about 2.5 kg/t also improved latex retention of fiber treated with HMDA modified polymer 25 although not to the same extent as with the Epi-DMA treated fib~r. With the HMDA modified sample, there did not appear to be significant advantage in using alum in amounts greater than 2.5 kg/t.
It is apparent that the partic~ar cationi~ing agent used will affect the finul fiber properties. Some age~ts will be optimum for certain 30 latices but will be less effective with others. There does not appear to be any way to predict this relationship and it must, to a large degree, be determined experimentally.
It will be eviden~ to those skilled in the art that many variations can be made without departing from the spirit of the present invention. The
3~ invention is to be considered as limited or~y by the ~ollowing claims.
Claims (22)
1. A cellulose based product which comprises:
a. a fibrous additive of cellulose with a material from the group consisting of a condensate of epichlorohydrin and dimethylamine, said condensate further modified by a crosslinking agents and mixtures thereof wherein the crosslinking agent, if present, is selected from the group consisting of ammonia and a primary aliphatic diamine of the type H2N-R-NH2 wherein R is an alkylene radical of from 2 to 8 carbon atoms;
and b. from 0.1 to 30%, on a dry weight basis, of a polymer capable of being emulsified into an anionic dispersion.
a. a fibrous additive of cellulose with a material from the group consisting of a condensate of epichlorohydrin and dimethylamine, said condensate further modified by a crosslinking agents and mixtures thereof wherein the crosslinking agent, if present, is selected from the group consisting of ammonia and a primary aliphatic diamine of the type H2N-R-NH2 wherein R is an alkylene radical of from 2 to 8 carbon atoms;
and b. from 0.1 to 30%, on a dry weight basis, of a polymer capable of being emulsified into an anionic dispersion.
2. The product of claim 2 in which the fibrous additive is made under alkaline conditions by treatment of cellulose with a condensate of essentially equimolar portions of epichlorohydrin and dimethylamine.
3. The product of claim 2 in which up to 30 molar percent of the dimethylamine is replaced by hexamethylene diamine.
4. The product of claim 2 in which up to 30 molar percent of the dimethylamine is replaced by ammonia.
5. The product of claim 2 in which up to 30 molar percent of the dimethylamine is replaced by ethylene diamine.
6. The product of claim 1 in which the additive material is present in an amount in the range of 0.5-20 kg/t based on the dry weight of cellulose.
7. The product of claim 6 in which the additive material is present in an amount in the range of 1-10 kg/t based on the dry weight of cellulose.
8. The product of claim 1 in which the polymer is selected from the group of crosslinking and noncrosslinking types of polyvinyl chloride, polyvinyl acetate, acrylonitrile, polystyrene, styrene-butadiene, styrene-acrylonitrile, acrylonitrile-butadiene-styrene, acrylic, vinyl acrylic resins, and polyolefins, mixtures thereof, and block and graft copolymers thereof.
9. The product of claim 8 in which the polymer is selected from the group of crosslinking and noncrosslining types of polyvinyl acetate and acrylic resins, mixtures thereof, and block and graft copolymers thereof.
10. The product of claim 3 in which the polymer is selected from the group of crosslinking and noncrosslinking types of polyvinyl chloride, polyvinyl acetate, acrylonitrile, polystyrene, styrene-butadiene, styrene-acrylonitrile, acrylonitrile-butadiene-styrene, acrylic, vinyl acrylic resins, and polyolefins, mixtures thereof, and block and graft copolymers thereof.
11. The product of claim 10 in which the polymer is selected from the group of crosslinking and noncrosslinking types of polyvinyl acetate and acrylic resins, mixtures thereof, and block and graft copolymers thereof.
12. A method for making a cellulose based product which comprises:
a. preparing a cationic cellulose product by treating cellulose under aqueous alkaline conditions with a material from the group consisting of a condensate of epichlorohydrin and dimethylamine, said condensate further modified by a crosslinking agent, and mixtures therof wherein the crosslinking agent, if present, is selected from the group consisting of ammonia and a primary aliphatic diamine of the type H2N-R-NH2 wherein R is an alkylene radical of from 2 to 8 carbon atoms; and b. further treating the cationized cellulose with an anionic polymer emulsion in an amount of from 0.1 to 30%, on a dry weight basis
a. preparing a cationic cellulose product by treating cellulose under aqueous alkaline conditions with a material from the group consisting of a condensate of epichlorohydrin and dimethylamine, said condensate further modified by a crosslinking agent, and mixtures therof wherein the crosslinking agent, if present, is selected from the group consisting of ammonia and a primary aliphatic diamine of the type H2N-R-NH2 wherein R is an alkylene radical of from 2 to 8 carbon atoms; and b. further treating the cationized cellulose with an anionic polymer emulsion in an amount of from 0.1 to 30%, on a dry weight basis
13. The method of claim 12 in which the cellulose is treated with a condensate of essentially equimolar portions of epichlorohydrin and dimethylamine.
140 The method of claim 13 in which up to 30 molar percent of the dimethylamine is replaced by ammonia.
15. The method of claim 13 in which up to 30 molar percent of the dimethylamine is replaced by ethylene diamine.
16. The method of claim 13 in which up to 30 molar percent of the dimethylamine is replaced by hexamethylene diamine.
17. The method of claim 12 further comprising using the condensate in an amount of 0.5 30 kg/t based on the dry weight of cellulose.
18. The method of claim 17 further comprising using the condensate in an amount of 1-10 kg/t based on the dry weight of cellulose.
19. The method of claim 12 in which the polymer emulsion is selected from the group of crosslinking and noncrosslinking types of polyvinyl chloride, polyvinyl acetate, acrylonitirle, polystyrene, styrene butadiene, styrene-acrylonitirle, acrylonitrile-butadiene-syrene, acrylic, vinyl acrylic resins, and polyolefins, mixtures thereof, and block and graft copolymers thereof.
20. The method of claim 19 in which the polymer is selected from the group of crosslinking and noncrosslinking types of polyvinyl acetate and acrylic resins, mixtures thereof, and block and graft copolymers thereof.
21. The method of claim 16 in which the polymer is selected from the group of crosslinking and noncrosslinking types of polyvinyl chloride, polyvinyl acetate, acrylonitrile, polystyrene, styrene butadiene, styrene-acrylonitrile, acrylonitrile-butadiene-styrene, acrylic, vinyl acrylic resins, polyolefins, mixtures thereof, and block and graft copolymers thereof.
22. The method of claim 21 in which the polymer is selected from the group of crosslinking and noncrosslinking types of polyvinyl acetate and acrylic resins, mixtures thereof, and block and graft copolymers thereof.
Priority Applications (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CA000474317A CA1249107A (en) | 1985-02-14 | 1985-02-14 | Latex treated cationic cellulose product and method for its preparation |
Applications Claiming Priority (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CA000474317A CA1249107A (en) | 1985-02-14 | 1985-02-14 | Latex treated cationic cellulose product and method for its preparation |
Publications (1)
| Publication Number | Publication Date |
|---|---|
| CA1249107A true CA1249107A (en) | 1989-01-24 |
Family
ID=4129834
Family Applications (1)
| Application Number | Title | Priority Date | Filing Date |
|---|---|---|---|
| CA000474317A Expired CA1249107A (en) | 1985-02-14 | 1985-02-14 | Latex treated cationic cellulose product and method for its preparation |
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| Country | Link |
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| CA (1) | CA1249107A (en) |
Cited By (1)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN114737200A (en) * | 2022-04-20 | 2022-07-12 | 国家纳米科学中心 | Dechlorination and corrosion inhibition method for iron object |
-
1985
- 1985-02-14 CA CA000474317A patent/CA1249107A/en not_active Expired
Cited By (2)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN114737200A (en) * | 2022-04-20 | 2022-07-12 | 国家纳米科学中心 | Dechlorination and corrosion inhibition method for iron object |
| CN114737200B (en) * | 2022-04-20 | 2024-05-28 | 国家纳米科学中心 | Dechlorination and corrosion inhibition method for iron articles |
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