JP3259649B2 - Resin composition for producing composite and composite - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

TECHNICAL FIELD The present invention relates to a resin composition for producing a composite and a composite. More specifically,
The present invention is a resin composition used in contact with a sulfur-vulcanized rubber composition, and does not cause discoloration such as yellowing, and has an excellent feature of maintaining a beautiful appearance at the beginning of use forever. The present invention relates to a resin composition for production and a composite using the resin composition.

[0002]

2. Description of the Related Art Composites having a layer made of a resin composition in contact with a layer made of a sulfur vulcanized rubber composition have been used in various fields. However, according to the conventional technique, there is a problem that discoloration such as yellowing occurs in a layer of the resin composition with the passage of time, and the appearance thereof is deteriorated.

[0003]

SUMMARY OF THE INVENTION In view of the foregoing, an object of the present invention is to provide a resin composition used in contact with a sulfur-vulcanized rubber composition, which causes discoloration such as yellowing. It is another object of the present invention to provide a resin composition for producing a composite and a composite using the resin composition, which have excellent characteristics of maintaining a beautiful appearance at the beginning of use.

[0004]

That is, one aspect of the present invention is a resin composition used in contact with a sulfur-vulcanized rubber composition, comprising the following components (A) and (B): The present invention relates to a resin composition for producing a composite. (A): thermoplastic resin (B): hydrotalcite

Another aspect of the present invention relates to a composite having a layer of a vulcanized rubber composition and a layer of the above-mentioned resin composition which is in contact with or pressed against the layer.

[0006]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS The component (A) of the present invention is a thermoplastic resin, specifically, an olefin resin, a vinyl resin represented by polyvinyl chloride, and an acrylic resin represented by polymethyl methacrylate. Resins and polystyrene resins.

When the type of rubber in the sulfur-vulcanized rubber composition is an ethylene-α-olefin rubber, an olefin resin is preferred from the viewpoint that heat fusion is possible. Examples of the olefin-based resin include polyethylene, polypropylene, and a copolymer of propylene and an α-olefin having 2 or more carbon atoms. Examples of the α-olefin having two or more carbon atoms include ethylene, 1-butene, 1-pentene, 3-methyl-1-butene, 1-hexene, 1-decene, 3-methyl-1-pentene, 4-
Methyl-1-pentene, 1-octene and the like can be mentioned. As the olefin resin, polyethylene and polypropylene are particularly preferable.

The component (B) of the present invention comprises a hydrotalcite
It is. Hydrotalcite is a known natural mineral
And the representative composition formula is Mg₆Al_Two(OH)₁₆CO_Three・
4H _TwoO and has a layered two-dimensional structure
(For example, the magazine “Polyfile (Polyfile)
No. 1995) No. 9 pages 45 to 50).

[0009] The content of (B) in the resin composition of the present invention is preferably 0.1 to 20 parts by weight per 100 parts by weight of (A). If the content of (B) is too small, the effect on discoloration may be insufficient, while if the content of (B) is too large, the appearance of the molded product may be impaired.

The method for obtaining the resin composition of the present invention includes:
Each of the above components (A) and (B), and, if necessary, inorganic fillers such as talc and calcium carbonate, which are usually blended with a thermoplastic resin, a plasticizer, a mineral oil-based softener, a flame retardant, and a lubricant. , An antistatic agent, a heat / light resistance stabilizer, an antiaging agent, etc., and kneading using an open roll, a Banbury mixer, an extruder, or the like.

The resin composition of the present invention may contain the following (C) in addition to the above (A) and (B). (C): ethylene-α-olefin copolymer rubber

Specific examples of (C) include ethylene-α-olefin copolymer rubber and ethylene-α-olefin-
Non-conjugated diene copolymer rubbers can be mentioned. α-
Examples of the olefin include propylene, 1-butene, 1-pentene, 1-hexene, 4-methyl-1-pentene, 1-octene, 1-decene and the like, with propylene being preferred. Examples of the non-conjugated diene include 1,4-hexadiene, dicyclopentadiene, 5-ethylidene-2-norbornene, and the like.

The ratio (weight ratio) of ethylene / α-olefin in (C) is usually 90/10 to 30/70. When the ethylene-α-olefin-non-conjugated diene copolymer rubber is used, the content of the non-conjugated diene is usually 5 to 40 in iodine value. The ethylene-α-olefin copolymer rubber and the ethylene-α-olefin-non-conjugated diene copolymer rubber may be used as a mixture. Further, oil-extended rubber may be used.

Preferred specific examples of the ethylene-α-olefin copolymer rubber include an ethylene-propylene copolymer rubber having a weight ratio of ethylene / propylene of 85/15 to 45/55.

[0015] Ethylene-α-olefin copolymer rubber
Is the Mooney viscosity at 100 ° C. (ML _{1 + 4}100 ° C) is 1
It is preferably from 0 to 350, more preferably from 30 to 3
00. If the Mooney viscosity is too low, the mechanical strength
If the Mooney viscosity is too high
The appearance of the molded article may be impaired.

When (C) is used, the resin composition of the present invention forms a so-called thermoplastic elastomer, and the sulfur-vulcanized rubber composition and the thermoplastic elastomer can be adhered by heat fusion, and the resulting resin is obtained. The effect that the laminate has the same flexibility as the vulcanized rubber can be obtained.

In the thermoplastic elastomer,
(A) is preferably an olefin resin, and (A) / (C)
Is 10/90 to 90/10, preferably 3/90.
0/70 to 80/20.

The content of (B) per 100 parts by weight of the total of (A) and (C) is preferably 0.1 to 20 parts by weight. If the content of (B) is too small, the effect on discoloration may be insufficient, while if the content of (B) is too large, the appearance of the molded product may be impaired.

Ethylene-α in the thermoplastic elastomer
-The olefin-based copolymer can be present in a crosslinked state such as uncrosslinked, partially crosslinked, or totally crosslinked.

In the method for producing a thermoplastic elastomer, the above-mentioned components and, if necessary, a crosslinking agent such as an organic peroxide are mixed and dynamically heat-treated, that is, melted and kneaded. As the kneading device, conventionally known devices such as an open-type mixing roll, a non-open-type Banbury mixer, an extruder, a kneader, and a continuous mixer can be used. Among these, it is preferable to use a non-open type device.

The resin composition of the present invention may contain the following (D) in addition to the above (A) and (B). (D): a vinyl aromatic compound-conjugated diene compound block copolymer or a hydrogenated product of the copolymer

The vinyl aromatic compound in the copolymer includes, for example, styrene, α-methylstyrene, P-methylstyrene, vinyltoluene and the like, among which styrene is preferred. Examples of the conjugated diene compound include butadiene, isoprene, 1,3-pentadiene, 2,3
-Dimethyl-1,3-butadiene and the like, among which butadiene and isoprene are preferred.

The structure of the copolymer is represented by the following general formula (AB)
n, A- (BA) n, B- (AB) n (where A is a polymer block mainly composed of a vinyl aromatic compound,
B is a polymer block mainly composed of a conjugated diene compound, but the boundary between the A block and the B block does not necessarily need to be clearly distinguished. N is an integer of 1 or more. ) Or a general formula [(AB) n] mx, [A- (BA) n] m
-X, [B- (AB) n] mX (where A and B are the same as above, X represents a branching agent residue, and n is 1
As described above, m is an integer of 3 or more. ) Is a branched (radial) block copolymer.

The number average molecular weight of the copolymer is usually 500
0 to 500,000, preferably 10,000 to 3
00000. If it is 5,000 or less, the mechanical strength becomes low, and if it is 500,000 or more, the viscosity of the polymerization solution becomes high. The content of the vinyl aromatic compound in the copolymer,
10 to 50% by weight is preferred.

The copolymer may be used as it is, but a product obtained by hydrogenating the copolymer is preferred in terms of light resistance, thermal stability and the like.

When (D) is used, the resin composition of the present invention forms a so-called thermoplastic elastomer similarly to the case where (C) is used, and the sulfur-vulcanized rubber composition and the thermoplastic elastomer are formed by heat. Adhesion can be achieved by fusion, and the resulting laminate can have the effect of having the same flexibility as vulcanized rubber.

In the thermoplastic elastomer,
(A) is preferably an olefin resin, and (A) / (D)
Is from 10/90 to 90/10, preferably,
30/70 to 80/20.

The content of (B) per 100 parts by weight of the total of (A) and (D) is preferably 0.1 to 20 parts by weight. If the content of (B) is too small, the effect on discoloration may be insufficient, while if the content of (B) is too large, the appearance of the molded product may be impaired.

The vinyl aromatic compound-conjugated diene compound block copolymer or the hydrogenated product of the copolymer in the thermoplastic elastomer can be present in a crosslinked state such as uncrosslinked, partially crosslinked or totally crosslinked. . Further, it may be used in combination with the above (C). The thermoplastic elastomer can be produced by the same method as in the case of using (C).

The weight ratio of (C) / (D) is 95/5 to 5
/ 95, and the content of (B) per 100 parts by weight of the total of (A), (C) and (D) is preferably 0.1 to 20 parts by weight. If the content of (B) is too small, the effect on discoloration may be insufficient, while if the content of (B) is too large, the appearance of the molded product may be impaired.

The resin composition of the present invention is a resin composition to be used in contact with a sulfur vulcanized rubber composition, that is, a layer composed of the sulfur vulcanized rubber composition and a resin composition in contact with the layer. It is a resin composition for producing a composite having a layer.

The above sulfur vulcanized rubber composition is a rubber composition which can be vulcanized with sulfur or a sulfur-containing compound as a crosslinking agent, and specific examples of rubber include ethylene-α-olefin-non-conjugated diene. Examples include copolymer rubber, natural rubber, isoprene rubber, butadiene rubber, styrene-butadiene copolymer rubber, acrylonitrile-butadiene copolymer rubber, and butyl rubber. Among the above, from the viewpoint of heat resistance and weather resistance, ethylene-α-olefin-
Non-conjugated diene copolymer rubbers are preferred. Ethylene-α-
Specific examples of the olefin-non-conjugated diene copolymer rubber include an ethylene-propylene-dicyclopentadiene copolymer rubber and an ethylene-propylene-ethylidene norbornene copolymer rubber. In addition,
To the rubber composition, carbon black, an inorganic filler, a mineral oil-based softening agent, a vulcanization aid, a vulcanization acceleration aid, an antioxidant, and the like which are usually compounded may be added.

As described above, the composite of the present invention has a layer composed of the sulfur vulcanized rubber composition and a layer composed of the resin composition in contact with the layer. The composite referred to here may be any as long as it has a layer made of a sulfur vulcanized rubber composition and a layer made of a resin composition in contact with the layer. Also includes those that can be moved by contact. Incidentally, as an example of the composite of the present invention,
Examples of the composite include a composite obtained by thermally fusing the layer of the vulcanized rubber composition and the layer of the resin composition, and a composite in which the vulcanized rubber composition and the resin composition are pressure-bonded. Specific examples of the composite include automobile interior parts and automobile exterior parts such as packing and sealing materials, waterproof sheets, and the like.

[0034]

Next, the present invention will be described by way of examples.

Example 1 20 parts by weight of polypropylene (melt flow index at 2.16 kg at 230 ° C. = 12 g / 10 min)
Ethylene-propylene-5-ethylidene-2-norbornene copolymer rubber (ethylene / propylene weight ratio = 79
/ 21, iodine value = 12) 80 parts by weight and 0.2 parts by weight of 2,5-dimethyl-2,5-di (tert-butylperoxy) hexane were melt-mixed for 12 minutes using a Banbury mixer, and then dynamically mixed. Heat-treated. Then, a paraffinic process oil (“Diana PW38” manufactured by Idemitsu Kosan Co., Ltd.)
0 ") 5 parts by weight and 1 part by weight of hydrotalcite (" DHT-4A "manufactured by Kyowa Chemical Industry Co., Ltd.) were added and mixed for 5 minutes.
Further, granulation was performed by a single screw extruder to obtain a pellet-shaped thermoplastic lastomer composition. The discoloration of the thermoplastic lastomer composition was evaluated by the following method. Table 1 shows the results. After 100 hours, almost no discoloration was observed, showing good results.

Comparative Example 1 The procedure of Example 1 was repeated except that no hydrotalcite was used. Table 1 shows the results. The color changed to yellow after 100 hours.

[Evaluation Method of Discoloration Property] The obtained thermoplastic elastomer composition was set in a mold having a thickness of 1 mm, heated at 200 ° C. for 5 minutes by a pressure press, and further cooled at room temperature for 5 minutes. And a sheet having a thickness of 1 mm. The vulcanized rubber sheet and the thermoplastic elastomer resin sheet described above were set in a mold having a thickness of 3 mm, heated at 220 ° C. for 10 minutes by a pressure press, and further cooled at room temperature for 5 minutes. Was obtained. The laminate is sunshine weathered o.
Meter (black panel temperature = 63 ° C, water flow for 12 minutes /
(60 minute cycle). After 100 hours, the degree of discoloration was evaluated according to JIS K 7105, and the color difference (ΔE) and the degree of yellowing (ΔYI) were determined.

Examples 2 to 6 Hydrotalcite (Kyowa Chemical's “D”) was used for various resins.
HT-4A ”) and titanium oxide were added, and the mixture was subjected to blend granulation using a single screw extruder to obtain a pellet-shaped resin composition. As a result of evaluating the discoloration property in the same manner as in Example 1, good results were shown. Table 2 shows the resin composition and evaluation results.
And Table 3.

Comparative Examples 2-5 Examples 2-5 except that no hydrotalcite was used.
Performed similarly to 6. As a result, the color changed to yellow. Tables 2 and 3 show the resin composition and evaluation results.

[0040]

[Table 1]

[0041]

[Table 2]

[0042]

[Table 3]

[0043]

As described above, according to the present invention, a resin composition to be used in contact with a sulfur-vulcanized rubber composition, which does not cause discoloration such as yellowing and has a beautiful appearance at the beginning of use. A resin composition for producing a composite having excellent characteristics of maintaining the same and a composite using the resin composition could be provided.

────────────────────────────────────────────────── ─── Continuation of the front page (56) References JP-A-6-246877 (JP, A) JP-A-6-246876 (JP, A) (58) Fields investigated (Int. Cl. ⁷ , DB name) B32B 25/00-27/42 C08L 23/00-23/36

Claims (19)

(57) [Claims] 1. A resin composition for use in contact with a sulfur-vulcanized rubber composition, which comprises the following components (A) and (B): (A): thermoplastic resin (B): hydrotalcite 2. The resin composition according to claim 1, wherein (A) is an olefin resin. 3. The resin composition according to claim 1, wherein (A) is polyethylene or polypropylene. 4. The resin composition for producing a composite according to claim 1, wherein the content of (B) per 100 parts by weight of (A) is 0.1 to 20 parts by weight. 5. In addition to (A) and (B), the following (C)
The resin composition for producing a composite according to claim 1, comprising: (C): ethylene-α-olefin copolymer rubber 6. The resin composition according to claim 5, wherein the content of (B) is 0.1 to 20 parts by weight per 100 parts by weight of the total amount of (A) and (C). 7. The weight ratio of (A) / (C) is 90/10
The resin composition for producing a composite according to claim 5, wherein the ratio is from 10 to 90/90. 8. The resin composition according to claim 5, wherein (C) is an ethylene-α-olefin copolymer rubber or an ethylene-α-olefin-nonconjugated diene copolymer rubber. 9. The resin composition for producing a composite according to claim 5, wherein (C) is an ethylene-propylene copolymer rubber. 10. The resin composition for producing a composite according to claim 1, further comprising (D) in addition to (A) and (B). (D): a vinyl aromatic compound-conjugated diene compound block copolymer or a hydrogenated product of the copolymer 11. The resin composition according to claim 10, wherein the content of (B) is 0.1 to 20 parts by weight per 100 parts by weight of the total amount of (A) and (D). 12. The weight ratio of (A) / (D) is 90/1.
The resin composition for producing a composite according to claim 10, wherein the ratio is from 0 to 10/90. 13. The resin composition according to claim 10, wherein (D) is a hydrogenated product of a styrene-butadiene or styrene-isoprene block copolymer. 14. The resin composition for producing a composite according to claim 1, comprising (C) and (D) in addition to (A) and (B). 15. A total of 10 of (A), (C) and (D)
The resin composition for producing a composite according to claim 14, wherein the content of (B) per 0 parts by weight is 0.1 to 20 parts by weight. 16. The resin composition for producing a composite according to claim 14, wherein the weight ratio of (A) / (C) and (D) is 90/10 to 10/90. 17. The weight ratio of (C) / (D) is 95/5.
The resin composition for producing a composite according to claim 14, wherein the ratio is from 5 to 95. 18. A composite having a layer of the vulcanized rubber composition and a layer of the resin composition according to claim 1, which is in contact with or pressed against the layer. 19. The composite according to claim 11, which is obtained by heat-sealing the layer of the vulcanized rubber composition and the layer of the resin composition according to claim 1.