CN101104665A - AM/NaAA/allyl cyclodextrin polymer with inclusion function and synthesis method - Google Patents

Abstract

The invention relates to an AM/NaAA/allyl cyclodextrin polymer with inclusion function and a synthesis method. It contains three structural units of acrylamide, sodium acrylate and allyl-cyclodextrin. The synthesis method is as follows: DMSO and DMF are used as solvents, CD is used as raw materials, and allyl cyclodextrin is synthesized at 0-10°C. Add AM to allyl cyclodextrin aqueous solution, and then add initiator, the total monomer concentration is 10-20%, the concentration of the initiation system is 40-80mg/l, the temperature is 30-50°C, and the time is 1-8h to prepare AM / allyl cyclodextrin binary copolymer. Add NaOH solution to the binary copolymer for hydrolysis to obtain AM/NaAA/allyl cyclodextrin polymer. The polymer synthesis method has mild conditions, simple operation and easy purification and separation of the obtained product. It can be used in fields such as oil exploitation, sewage treatment, chemical industry and medicine.

Description

AM/NaAA/allyl cyclodextrin polymer with inclusion function and synthesis method

technical field

The invention relates to an AM/NaAA/allyl cyclodextrin polymer with inclusion function and a synthesis method thereof, which can be used in the fields of petroleum exploitation, sewage treatment, chemical industry, medicine and the like.

Background technique

Polyacrylamide water-soluble polymers have attracted more and more attention due to their good viscoelasticity during oil displacement (Ahmad Rabiee, M. Ebrahim Zeynali, and Habibollah Baharvandl. Synthesis of High Molecular Weight Partially Hydrolyzed Polyacrylamide and Investigation on its Properties. Iranian Polymer Journal, 14(7), 2005, 603-608). Since this type of polymer can not improve the interfacial tension between oil-water-rock as an oil displacement agent, the introduction of surface active groups into polyacrylamide polymers has become a research hotspot for scientists at home and abroad. Acrylamide and Cationic Copolymerization Containing Unsaturated Bonds (Tao Youhe. Preparation method of ultra-high molecular cationic polyacrylamide, 200510037817.7; Xu Zhenju; Xue Xiuying; Xu Guangyu. Preparation method of cationic polyacrylamide, Chinese invention patent, 200610042600.X; JoséR .Ochoa G.，Franci sca Río，Pedro M.Synthesis of cationic flocculants based on acrylamide and[2-(acryloyloxy)ethyl]trimethylammonium chloride co polymersby semicontinuous inverse microemulsion co polymerization.PartI：Criteria for selection of comonomer formulation，e-Polymers2006 , 25:1-14), and the anionic copolymerization with unsaturated bonds (Wang Hongyun. Preparation method of high molecular weight anionic polyacrylamide, Chinese invention patent, 96115823.9) and many other reports. However, because acrylamide polymers containing surface active groups are charged and easily adsorbed by formation clay minerals, they are limited in enhancing oil recovery. Cyclodextrin has a hydrophobic inner cavity and a water-soluble outer wall. Its application is mainly to form a supramolecular system with inclusion function. Many polymers have been successfully prepared and applied in the fields of environmental purification, chemical industry and medicine.

Contents of the invention

The object of the present invention is to provide AM/NaAA/allyl cyclodextrin polymer with inclusion function and its synthesis method. The polymer has an inclusion function, not only can include long-chain anionic surfactants, but also can include cationic surfactants, so that the acrylamide polymer with surface active groups is prevented from formation adsorption.

A new type of water-soluble AM/NaAA/allyl cyclodextrin polymer with inclusion function, including three structural units of acrylamide (AM), sodium acrylate (NaAA), and allyl cyclodextrin. The structural formula is as follows:

Wherein the molar percentage of X is 0.8%, and the molar percentage of Y is 0-37.2%

Accompanying drawing is infrared analysis spectrogram.

The absorption peaks are assigned in Table 1.

Table 1 Infrared analysis (v stretching vibration, δ bending vibration)

  Peak position cm-1 attribution 3447.43 v(O-H)+v(N-H)   2929.06 v(CH ₂ )   1655.02 v(C＝O)   1457.56 δ(CH ₂ ) 1408 δ(OH) plane bending 1340 δ(CCH)+δ(COH) 1236 v(CO)+δ(CCH)+δ(OOH)(O-H plane bending) 1160 v(C-O-C) 1080 v(co)+δ(COH)+v(CC)   1026.22 vCC+δ(CCH)+δ(OCH) 960 CD framework vibrations including α-1,4-bonds 880 δ(CCH)+v(C-O)+v(C-C vibration) 575.28 Skeleton vibration (ring vibration)

The synthetic method of AM/NaAA/allyl cyclodextrin polymer comprises the following steps successively:

Using the mixture of dimethyl sulfoxide (DMSO) and N,N-dimethylformamide (DMF) as the reaction solvent and cyclodextrin as the raw material, the reaction temperature is 0-10°C, and the reaction time is 1-8 hours. Monomer allyl cyclodextrin with inclusion function; in the aqueous solution of allyl cyclodextrin, add AM, then add initiator ammonium persulfate solution, the total monomer concentration is 10-20%, allyl cyclodextrin The weight ratio of essence and AM is 2.7:100~13.2:100, the concentration of the initiation system is 40-80mg/L, the polymerization reaction temperature is 30-50°C, the reaction time is 1~8h, and the oxygen is filled with nitrogen for 20-40min, after sealing React in a constant temperature water bath to prepare AM/allyl cyclodextrin binary copolymer. NaOH solution is added as a hydrolyzing agent in an amount of 1/125-1/10 (weight ratio) of the polymer. The concentration of the binary polymer is 2-6%, and the hydrolysis temperature is 30-70°C. After the dispersion is uniform, it is placed in a constant temperature water bath for hydrolysis reaction to obtain 0-37.29% AM/NaAA/allyl cyclodextrin polymer.

In the present invention, the allyl cyclodextrin monomer with inclusion function is firstly prepared. Since both cyclodextrin (CD) and allyl bromide are soluble in DMSO, a mixture of DMSO and DMF is used as the reaction solvent. Adding NaOH to the reaction system can speed up the reaction, the reaction temperature can be between 0-10°C, and the yield is the highest at 2°C. The reaction time is 1-48h, and the yield is the highest at 48h. After the reaction stopped, DMSO and DMF were removed by vacuum filtration, the white powder was washed with acetone, and the calculated yield was 76.2% after drying.

First weigh the required amount of allyl cyclodextrin, add the required amount of distilled water, and then place it in a constant temperature water bath at 40°C until the allyl cyclodextrin is completely dissolved, then add the required amount of AM to fully Deoxygenate with nitrogen for 20-30 minutes, then add the prepared initiator, seal and place in a constant temperature water bath at the required temperature, and react for a certain period of time. The initiator can be ammonium persulfate, potassium persulfate, azobisisobutyronitrile, potassium persulfate/sodium bisulfite, potassium persulfate/tertiary amine, etc. The concentration of the initiation system is 40-80mg/L, the polymerization reaction temperature is 30-50°C, and the total monomer concentration is 10-20%. The polymer prepared at 20% has good water solubility and viscosity. The molecular weight of the polymer is above 3 million.

The hydrolysis process is mainly carried out in 40-45% NaOH solution, the hydrolysis temperature is 50-70°C, the polymer concentration is about 1-4% during hydrolysis, and the degree of polymer hydrolysis is controlled by the amount, concentration, and hydrolysis time of the hydrolyzing agent . The invention obtains the AM/NaAA/allyl cyclodextrin ternary polymer with a hydrolysis degree of 0-37.2%.

The separation and purification of the polymer adopts the method of adding ethanol to the polymer reaction system, reprecipitating the ternary polymer with inclusion function, collecting and drying under reduced pressure.

Compared with the prior art, the invention has the following beneficial effects: the preparation method of the AM/NaAA/allyl cyclodextrin polymer is simple and feasible, the reaction conditions are mild, and the product is easy to purify and separate. The polymer prepared by the method can be organically combined with a surfactant to form a supramolecular clathrate, and can be used in industries such as oil exploitation and sewage treatment.

Detailed ways:

Synthesis of Example 1 Allyl Cyclodextrin

Put 5.7g (5mmol) β-CD in a beaker, add 30mL DMSO and 50mL DMF to dissolve it, then add 2.0g NaOH, place it on a magnetic stirrer and stir for about 1h. The color of the solution gradually deepened and turned yellow, and the pH value was 9 at this time. At 0°C to 10°C, 8.0 mL of propene bromide was slowly added dropwise twice, and stirred with a magnetic stirrer, the pH value dropped to 7, the color of the solution became light yellow, and precipitation began to appear after 24 hours of reaction. After 48 hours the reaction was stopped and a white precipitate was obtained. DMSO was removed by vacuum filtration, and the precipitate was washed with acetone to obtain 6.10 g (yield: 72.6%) of white powder, which was sealed and stored in cold storage.

Example 2 has the binary polymer composition of inclusion function

Weigh allyl cyclodextrin monomer and distilled water according to the ratio in Table 2, put them in a 100mL Erlenmeyer flask, put them in a constant temperature water bath at 40°C to dissolve them completely, then weigh acrylamide and add them into the solution, and wait until it is completely dissolved , after passing _N2 for about 20 minutes, add the pre-prepared ammonium persulfate solution (8 mg/mL) and continue to pass nitrogen for 10 minutes, seal and react at a constant temperature of 45 ° C for 8 h, precipitate with absolute ethanol, and dry under vacuum at 40 ° C to obtain the polymer .

Table 2 binary polymer preparation

Drugs Amount added (g) Allyl cyclodextrin 0.157 distilled water 25 AM 5.0 NH ₄ S ₂ O ₈ 2.9×10 ^-3

Example 3 binary copolymers are hydrolyzed into ternary polymer synthesis

In a 250mL Erlenmeyer flask, add 0.5g of the binary copolymer synthesized in the above example and 100mL of distilled water. After the polymer is completely dissolved, add the hydrolysis agent NaOH according to Table 3, react at 50°C for 4h, and precipitate the polymer with acetone. , and then vacuum-dried at 40°C to obtain terpolymers with different degrees of hydrolysis, see Table 3 for details.

Table 3 Terpolymer hydrolysis degree

NaOH(g)   Degree of hydrolysis (%) 0.04 6.5 0.12 13.7 0.24 24.0 0.32 30.0 0.50 35.0

Rheology of Example 4AM/NaAA/Allyl Cyclodextrin Polymer

Table 4 shows the change of the viscosity of the polymer with the concentration when the concentration of the polymer with a degree of hydrolysis of 13.7 is lower than 0.001 g/mL. As can be seen from Table 4, when the polymer concentration is lower than 0.0015g/mL, the relative viscosity of the polymer solution rises slowly with the increase of the polymer concentration; when the polymer concentration exceeds 0.0015g/ml, the viscosity of the solution is significantly Increase, showing the viscosity-increasing performance of partially hydrolyzed polyacrylamide.

Table 4 Rheology of AM/NaAA/allyl cyclodextrin polymers

Polymer concentration (g/mL) 0.004 0.0008 0.0012 0.0016 0.002 0.0024 0.0028 Relative viscosity (mPa·S) 16.76 33.66 108.63 160.71 237.45 314.56 378.4

Salt Resistance of Example 5AM/NaAA/Allyl Cyclodextrin Polymer

Table 5 shows the change of the viscosity of the polymer solution with a degree of hydrolysis of 13.7 with the addition of inorganic salts. It can be seen from Table 5 that the viscosity retention rate of polyacrylamide with the same degree of hydrolysis in brine with a salinity of 1.6×10 ⁵ mg/L is only 10.6%, while that of AM/NaAA/allyl cyclodextrin polymer The viscosity retention rate reaches 32.5%, which is about 3 times higher.

Table 5 Comparison of salt resistance between polyacrylamide with the same degree of hydrolysis and AM/NaAA/allyl cyclodextrin polymer

polymer ηdistilled water/mPa·S ηSalt water/mPa·S Viscosity retention% Hydrolyzed polyacrylamide 112.45 11.92 10.6 AM/NaAA/Allyl Cyclodextrin Polymer 108.63 35.3 32.5

Inclusion Behavior of Example 6 Surfactant in AM/NaAA/Allyl Cyclodextrin Polymer

Table 6 shows the surface tension changes of the surfactant cetyltrimethylammonium chloride in the polymer solution. It can be seen from Table 6 that the surface tension of the polymer solution hardly decreases before the addition of surfactant is 0.070mmol/L. It shows that the added surfactant enters the hydrophobic cavity of cyclodextrin in the polymer. When the addition amount is close to the cyclodextrin content in the polymer, the surface tension of the polymer solution begins to decrease. It shows that cyclodextrin assembled surfactant molecules reached saturation.

Table 6 The surface tension change of the polymer at different additions of surfactant

Dosagemmol/L 0 0.035 0.070 0.10 0.15 0.4 0.5 Polymer surface tension mN/m 71.3 71.2 69.8 62.3 50.6 46.7 41.2 Aqueous solution surface tension mN/m 73.1 62.3 51.2 49.4 45.2 41.8 40.9

Claims (4)

1. The AM/NaAA/allyl cyclodextrin polymer with inclusion function contains three structural units of acrylamide, sodium acrylate, and allyl cyclodextrin, and its structural formula is as follows:

Wherein the molar percentage of X is 0.8%, and the molar percentage of Y is 0-37.2% 2. have the synthetic method of inclusion functional AM/NaAA/allyl cyclodextrin polymer as claimed in claim 1, it is characterized in that: with dimethyl sulfoxide (DMSO) and N,N-dimethyl Formamide (DMF) mixture is used as the reaction solvent, cyclodextrin is used as the raw material, the reaction temperature is 0-10°C, the reaction time is 1-8 hours, and the monomer allyl cyclodextrin with inclusion function is synthesized; In the cyclodextrin aqueous solution, add AM, then add the initiator ammonium persulfate solution, the total monomer concentration is 10-20%, the weight ratio of allyl cyclodextrin to AM is 2.7:100~13.2:100, the concentration of the initiator system 40-80mg/L, the polymerization reaction temperature is 30-50°C, the reaction time is 1-8h, filled with nitrogen and deoxygenated for 20-40min, sealed and placed in a constant temperature water bath to prepare AM/allyl cyclodextrin binary Copolymer; NaOH solution is added as a hydrolyzing agent, the amount of which is 1/125 to 1/10 of the polymer, which is the weight ratio, the concentration of the binary polymer is 2-6%, the hydrolysis temperature is 30-70°C, and the dispersion is uniform Place in a constant temperature water bath for hydrolysis reaction to obtain 0-37.29% AM/NaAA/allyl cyclodextrin polymer. 3. synthetic method according to claim 2, it is characterized in that: initiator uses ammonium persulfate, also can use potassium persulfate, azobisisobutyronitrile, potassium persulfate/sodium bisulfite, potassium persulfate/ tertiary amine. 4. The synthesis method according to claim 2, characterized in that: the hydrolysis process is carried out in 40-45% NaOH solution, the hydrolysis temperature is 50-70°C, the polymer concentration is 1-4% during hydrolysis, and the polymerization The degree of hydrolysis of the product is controlled by the amount, concentration, and hydrolysis time of the hydrolyzing agent.

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