CN100344654C - Method for preparing water soluble polymer material - Google Patents

Abstract

The present invention belongs to the technical field of preparing cationic water-soluble macromolecule material. The water-soluble macromolecular material of the present invention is a cationic macromolecule polymer with high molecular weight, which is formed by synthesizing a cationic macromolecule crosslinking agent and nonionic and/or cationic monomers in a reaction mode; the water-soluble macromolecular material mainly comprises the steps: (1) the preparation of the cation polymer crosslinking agent and (2) the preparation of the water-soluble macromolecular material. The prepared products can be used in the fields of paper making, printing, etc.

Description

A kind of preparation method of water-soluble polymer material

technical field

The invention belongs to the technical field of preparation of water-soluble polymers.

Background technique

Acrylamide water-soluble polymers are widely used in the paper industry. As paper strengthening agents, the molecular weight of acrylamide polymers has a great influence on the strength of paper. Generally, the larger the molecular weight, the better the strengthening effect. As a pulp pretreatment agent, the molecular weight of polyacrylamide polymer is higher than that of condensation cationic polymer. However, adding polyacrylamide with a molecular weight exceeding a certain value will cause the pulp to flocculate, destroy the evenness of the paper, and reduce the strength of the paper.

The preparation method of paper strengthening agent with high molecular weight and low flocculation generally adopts the method of adding crosslinking agent. Commonly used crosslinking agents are methylene N, N-diacrylamide, triallylamine or allylated cellulose. However, due to the short distance between the two double bonds in the methylene N, N-diacrylamide structure, the steric resistance effect is large, which affects the uniformity of the crosslinking point. Japanese patent (Japanese Patent Laid-Open No. 10-218797) proposes a method for improving crosslinking uniformity by adjusting the ratio of polymer monomers, but it does not fundamentally solve the problem that the molecular weight of the polymer is affected by the small molecular weight of the crosslinking agent. In addition, the reactivity of triallylamine or allylated cellulose is low, which affects the reaction degree of copolymerization.

In order to solve the above problems, the present invention designs and synthesizes a cationic polymer cross-linking agent with a vinyl end segment, which well solves the problems of low reactivity and uneven cross-linking density of traditional cross-linking agents.

Contents of the invention

The purpose of the present invention is to prepare water-soluble polymer by copolymerization of cationic polymer cross-linking agent represented by chemical general formula 1 and methacrylamide or acrylamide and water-soluble monomer represented by chemical general formula 2 The material prepares a cross-linked cationic water-soluble polymer material containing cationic components, which solves the above-mentioned technical problems.

Implement the technical scheme of the present invention as follows:

①. Preparation of cationic polymer crosslinking agent.

The cationic polymer crosslinking agent represented by chemical formula 1 used in the present invention is composed of epihalohydrin and alkylamines such as ammonia, primary organic amines, secondary organic amines and tertiary organic amines. Epihalohydrin refers to epichlorohydrin, epibromohydrin and epoxy iodopropane, one of which can be used or two or more can be used in combination; organic primary amines are methylamine, ethylamine, n-propylamine, isopropylamine ;Organic secondary amine refers to dimethylamine, diethylamine, dipropylamine, methylethylamine, methylpropylamine, diphenylamine and their combination; the acyl monomer containing organic tertiary amine is N,N-dimethylaminopropyl Methacrylamide, N,N-Dimethylaminopropylacrylamide, N,N-Diethylaminopropylmethacrylamide, N,N-Diethylaminopropylacrylamide, N,N- Dimethylaminobutylmethacrylamide, N,N-dimethylaminomethacrylamide, N,N-methylethylaminopropylacrylamide, N,N-dimethylaminopropylmethacrylate, N, Propylamine N-dimethylaminoacrylate, N,N-dimethylaminomethylaminomethacrylate, N,N-dimethylaminomethylaminomethacrylate are suitable for use in the present invention. Among acrylamides, N, N-dimethylaminopropyl acrylamide is especially recommended because it has better alkali resistance than those containing ester groups in the structure.

The terminal of the cationic polymer crosslinking agent represented by Chemical Formula 1 contains two vinyl groups.

Chemical formula 1 is:

Where R ₁ , R ₂ , R ₃ , R ₄ , R ₅ = hydrogen, alkyl or benzyl with 1-3 carbons, R ₆ = hydrogen or methyl, n = 0-50, B = O or NH , X=halogen;

To prepare cationic polymer crosslinking agent, the feeding sequence is as follows: put epihalohydrin into the reactor, drop ammonia, primary amine or secondary amine, after the two react, add vinyl monomer containing tertiary amine group for reaction ; It is also possible to add ammonia, primary or secondary amines, and vinyl monomers containing tertiary amine groups dropwise to the reactor with epihalohydrin, but avoid using the opposite addition step. Because ammonia, primary amines, secondary amines and vinyl monomers are prone to Michael addition reactions, the method of dropping ammonia, primary amines, and secondary amines into epihalohydrin can obtain cationic products containing halogens at the end. It is easy to react with vinyl monomers containing tertiary amine groups.

In the cationic polymer crosslinking agent represented by chemical general formula 1, the molar ratio of ammonia, primary amine, secondary amine to epihalohydrin is properly adjusted according to the nature, structure and molecular weight of the desired crosslinking agent, between 0.15- 1.20 molar range. When the molar ratio is less than 0.15, epihalohydrin is likely to remain, and when the molar ratio is greater than 1.20, it is difficult to form a terminal with a halogen, so that it cannot react with vinyl monomers containing tertiary amino groups.

The molar ratio of vinyl monomers containing tertiary amine groups to epihalohydrin is required to be 0.15-0.24. If this value is exceeded, there will be unreacted vinyl monomers containing tertiary amine groups in the product.

In the preparation of the cationic polymer crosslinking agent represented by chemical formula 1, ammonia, primary amine, and secondary amine can react with epihalohydrin to obtain a cationic resin easily. When the ratio of ammonia, primary amine, secondary amine to epihalohydrin is 0.15-1.0, adding a basic catalyst such as sodium hydroxide can accelerate the reaction. According to the required properties, structure, molecular weight, etc., the reaction temperature can be adjusted appropriately to 10-90°C, and 20-60°C is recommended. The reaction speed is slow below 20°C, and the halogen at the end of the resin obtained above 60°C is hydrolyzed and cannot react with vinyl monomers containing tertiary amine groups. The reaction time is within 1-24 hours.

②Preparation of water-soluble polymer materials. The cationic polymer cross-linking agent represented by chemical formula 1 is copolymerized with a monomer mixture composed of methacrylamide or acrylamide and a water-soluble monomer represented by chemical formula 2, and a cross-linking agent containing cationic components is prepared. A water-soluble polymer material of the joint type.

Chemical formula 2 is:

Wherein R ₇ ＝H, CH ₃ , R ₈ , R ₉ ＝ alkyl or alkoxy with 1-3 carbons, R ₁₀ ＝H or alkyl, alkoxy or benzyl with 1-3 carbons, E =O or NH, F=alkyl or alkoxy group with 1-3 carbons, Y=negative counter ion.

The method for preparing water-soluble macromolecular material of the present invention, the preparation method that general free radical polymerization is used all is applicable to the present invention: the weight percent concentration that monomer occupies in the reaction solution is 5-30% when using aqueous solution polymerization method ; When the concentration is 20-70%, the method of dispersion polymerization or inverse emulsion polymerization can be used.

The initiator used is a water-soluble polymer, and the initiators suitable for polymerization are azo and redox. The usage amount of the azo initiator is 0.001-1% of the total amount of the monomers, and the amount of the redox initiator is 0.001-1% of the total amount of the monomers.

The polymerization is carried out under the protection of inert gas, and the reaction temperature is 15-95°C, 20-75°C is recommended. The reaction rate is slow below 20°C, and the reaction is difficult to control above 90°C.

The water-soluble polymer material prepared by the invention is a graft copolymer with cationic groups on the side chain, and the molecular weight is generally 10,000-15,000,000.

The water-soluble polymer material of the present invention is suitable for various papermaking additives, for example, when used as a paper strengthening agent, it is in the range of 100,000-8,000,000 when converted into a linear polymer. The use method is the same as the existing method, such as adding a cationic preparation with a pulp solid content of 0.01-2% to the pulp with a solid content of 0.5-3% to make paper. There is no limit to the type of pulping, and mechanical pulping, mixed pulping, and waste pulp are all applicable. Especially when B in Chemical Formula 1 is an -NH- group, the pH during papermaking can be in a relatively high range between neutral and weakly alkaline.

The following examples will further describe the present invention, but it does not limit the rights of the present invention.

Embodiment (one). The embodiment of the preparation of the cationic polymer cross-linking agent represented by general chemical formula 1:

Add 150g of epichlorohydrin into a four-necked flask equipped with a thermometer, a stirring rod, and a dropping funnel, and add 145g of a 33% aqueous solution of dimethylamine dropwise at 40-50°C within 2 hours. ℃ of reaction for 1 hour; (at this time, the reaction conversion rate of dimethylamine was shown to be 100% by gel titration; in addition, 0.67% of tertiary amine was generated by amine neutralization titration; The result of chromatographic determination shows that the conversion rate of epichlorohydrin is 100%);

After the reaction, 21.0 g of dimethylaminopropyl acrylamide was added to the system, reacted at 25° C. for 15 hours, and 36.5 g of deionized water was added to obtain 327.9 g of a 70% light yellow water-soluble cationic polymer crosslinking agent. (As measured by the amine neutralization titration method, 8.5% of tertiary amines were produced, the weight average molecular weight was 1,460 in terms of polyacrylamide molecular weight, and the cationic degree was 6.52meq/g.)

Detailed ways

The following are examples of the preparation of water-soluble polymer materials:

Example 1

In the there-necked flask equipped with a thermometer and a stirrer, add 17.8 g of crosslinking agent 17.8 g of 50% concentration prepared in the above-mentioned embodiment (1), 95.0 g of acrylamide of 50% concentration and 6.0 g of acrylic acid aqueous solution of 60% concentration, and use ammonia water and Deionized water was used to adjust the pH to 3.5 and to make the total amount 270 g. Under nitrogen protection, 1.5 g of 10% concentration of ammonium persulfate and 4.8 g of 10% concentration of sodium bisulfite were added, and the reaction was static at room temperature 25° C. for 12 hours. After the reaction, 23.7 g of deionized water was used to adjust the polymer concentration to 20%. The results are shown in Table 1.

Example 2

In the there-necked flask equipped with a thermometer and a stirrer, add 16.8 g of cross-linking agent at 50% concentration, 84.0 g of acrylamide at 50% concentration, 5.7 g of acrylic acid at 60% concentration and dimethylamino group prepared in the above embodiment (1). 6.2 g of ethyl methacrylate, adjust the pH value to 3.5 with hydrochloric acid, add 1.5 g of ammonium persulfate of 10% concentration and 4.5 g of sodium bisulfite of 10% concentration under the protection of nitrogen, and react at room temperature 25 ° C for 12 hours, After the reaction, 24 g of deionized water was used to adjust the polymer concentration to 20%. The results are shown in Table 1.

Example 3

In the there-necked flask equipped with a thermometer and a stirrer, add 0.96 g of the 50% concentration cross-linking agent prepared in the above-mentioned embodiment (1), 30 g of methacryloyloxyethyltrimethylammonium chloride of 80% concentration, concentration 0.48g of 1% concentration of 2-methyl-allyl sodium sulfonate and 88.56g of deionized water, warming up to 60°C, adding 0.6g of 10% concentration of V50 initiator under nitrogen protection, and stopping the reaction after 4 hours of reaction , adding 1.8 g of deionized water to adjust the polymer concentration to 20%, the results are shown in Table 1.

Example 4

In a three-necked flask equipped with a thermometer and a stirring device, add 50% of the crosslinking agent prepared in the above example (1), 25g of dimethylaminopropyl acrylamide, and 1% of 2-methyl-allyl 8g of sodium sulfonate and 82g of deionized water, heated up to 60°C, added 0.6g of V50 initiator with a concentration of 10% under nitrogen protection, terminated the reaction after 4 hours of reaction, added 6.25g of deionized water to adjust the polymer concentration to 20 %, the results are shown in Table 1.

Example 5

In the there-necked flask equipped with a thermometer and a stirring device, add 1.32 g of the 50% concentration crosslinking agent prepared in the above-mentioned embodiment (1), 30 g of 80% concentration of acryloyloxyethyltrimethylammonium chloride, 1% Concentration 0.72g of sodium 2-methyl-allyl sulfonate and 87.96g of deionized water, warming up to 60°C, adding 0.6g of 10% V50 initiator under the protection of nitrogen, and stopping the reaction after 4 hours of reaction, adding 2.7 g of ionized water was used to adjust the polymer concentration to 20%. The results are shown in Table 1.

The following are comparative examples:

Comparative example 1

Add 96.2g of acrylamide with a concentration of 50%, 5.6g of acrylic acid with a concentration of 60%, and 8.6g of ethyl dimethylaminoacrylate in a three-necked flask equipped with a thermometer and a stirring device, adjust the pH value to 3.5 with aqueous hydrochloric acid, and add Ionized water adjusts the total system weight to 270g. Raise the temperature to 60°C, add 1.35g and 1.35g of ammonium persulfate and sodium bisulfite with a concentration of 10% respectively, and stop the reaction for 12 hours under the protection of nitrogen, and adjust the polymer concentration to 20% with deionized water. The results are shown in Table 1 .

Comparative example 2

Add 96.2g of 50% concentration of acrylamide, 5.6g of 60% concentration of acrylic acid, 8.6g of ethyl dimethylaminoacrylate, 1% concentration of methylene N, N-di 3.0 g of acrylamide and 1.8 g of 1% sodium 2-methyl-allylsulfonate were used to adjust the pH value to 3.5 with aqueous hydrochloric acid, and the total system weight was adjusted to 270 g by adding deionized water. Raise the temperature to 60°C, add 1.74g and 1.74g of ammonium persulfate and sodium bisulfite with a concentration of 10% respectively, and stop the reaction for 12 hours under the protection of nitrogen, and adjust the polymer concentration to 20% with deionized water. The results are shown in Table 1 .

Table 1 20% aqueous solution viscosity (mpa.s) Weight average molecular weight/Mw Molecular weight distribution/Mn/Mw Example 1 4220 594,000 13.6 Example 2 1530 369,000 13.5 Example 3 1600 195,000 12.8 Example 4 1784 195,000 15.4 Example 5 2340 107,000 10.9 Comparative example 1 16700 326,000 2.21 Comparative example 2 13000 428,000 2.67

Viscosity of 20% aqueous solution can be seen by rotary viscosities. Compared with comparative examples, the molecular weight distribution of the prepared products is very wide, indicating that the effect of the new crosslinking agent is very obvious.

Claims (6)

1, a kind of preparation method of water-soluble high-molecular material, its preparation process and condition comprise:

2. the preparation of water-soluble high-molecular material: be exactly the monomer system copolymerization of the cation type polymer linking agent of representing with chemical formula 1 that 1. prepares with step and the water-soluble monomer formation of Methacrylamide or acrylamide and chemical general formula 2 expressions, prepare a kind of water-soluble high-molecular material;

Said chemical general formula 2 is:

R wherein ₇=H, CH ₃, R ₈, R ₉The alkyl of=carbon number 1-3 or alkoxyl group, R ₁₀The alkyl of=H or carbon number 1-3, alkoxyl group or benzyl, E=O or NH, alkyl or the alkoxyl group of F=carbon number 1-3, Y=bears counter ion;

The preparation method that general radical polymerization is used is applicable to the present invention: the weight percent concentration that monomer is occupied in reaction soln is used water solution polymerization process when 5-30%; Concentration can be with the method for dispersion polymerization or inverse emulsion polymerization when 20-70%;

The initiator that uses is that the initiator that the water-soluble polymer polymerization is suitable for is azo class, redox class, and the usage quantity of azo-initiator is the 0.001-1% of monomer total amount, and the initiator usage quantity of redox class is the 0.001-1% of monomer total amount; Polymerization is carried out under protection of inert gas, temperature of reaction 15-95 ℃;

It is characterized in that the present invention also comprises the preparation of step cation type polymer linking agent 1.:

The cation type polymer linking agent of representing with chemical formula 1 is to be made of epoxyhalopropane and ammonia, organic primary amine, organic secondary amine and trimethylamine; Epoxyhalopropane is meant epoxy chloropropane, epoxy bromopropane and epoxy iodopropane, can use wherein a kind of also can be used in combination; Organic primary amine is meant methylamine, ethamine, Tri N-Propyl Amine, Isopropylamine; Organic secondary amine refer to dimethylamine, diethylamine, dipropyl amine, thyl methyl amine, first propylamine, pentanoic with and mutual combination; The acyl group monomer that contains organic tertiary amine is N, N dimethylamine base propyl methyl acid amides, N, N dimethylamine base propyl group acrylamide, N, N dimethylamine base propyl methyl acid amides, N, N dimethylamine base propyl group acrylamide, N, N dimethylamine base butyl methyl acrylamide, N, N dimethylamine ylmethyl Methacrylamide, N, the N-first and second aminocarbonyl propyl acrylamides, N, N dimethylamine ylmethyl vinylformic acid propylamine ester, N, N dimethylamine base vinylformic acid propylamine ester, N, N dimethylamine ylmethyl vinylformic acid methylamine ester;

Preparation cationic polymers linking agent, its order of addition(of ingredients) is: epoxyhalopropane is added in the reactor, drip ammonia, primary amine or secondary amine, the two reaction back adds the vinyl monomer that contains tertiary amine group and reacts; The vinyl monomer that also can drip ammonia, primary amine or secondary amine in the reactor that is added with epoxyhalopropane and contain tertiary amine group reacts, but avoid using opposite addition step, because Michael reaction takes place in ammonia, primary amine, secondary amine and vinyl monomer easily, can obtain the cationic product that end contains halogen so earlier ammonia, primary amine, secondary amine are splashed into the method for epoxyhalopropane, react than the vinyl monomer that is easier to containing tertiary amine group like this;

The end of the cationic polymers linking agent that said chemical formula 1 is represented contains two vinyl groups;

Chemical formula 1 is:

R wherein ₁, R ₂, R ₃, R ₄, R ₅The alkyl of=hydrogen, carbon number 1-3 or benzyl,, R ₆=hydrogen or methyl, n=0-50, B=0 or NH, X=halogen;

The cationic polymers linking agent represented of preparation chemical formula 1, ammonia, primary amine, secondary amine respectively with the ratio of epoxyhalopropane in the 0.15-1.20 molar range; The proportion requirement that contains the vinyl monomer of tertiary amine group and epoxyhalopropane is in the 0.15-0.24 molar range;

Temperature of reaction is at 10-90 ℃;

Reaction times is in 1-24 hour.

2,, it is characterized in that the B of the chemical formula 1 of said step in 1. be-NH-formation cation type polymer linking agent by the preparation method of the said a kind of water-soluble high-molecular material of claim 1.

3, the preparation method by claim 1 or the said a kind of water-soluble high-molecular material of 2 any one claim is characterized in that, the temperature of reaction of said step in 1. is 20-60 ℃.

4, by the preparation method of the said a kind of water-soluble high-molecular material of claim 1, it is characterized in that, said step 1. in, when ammonia, primary amine, secondary amine respectively when the ratio of epoxyhalopropane is in the 0.15-1.0 molar range, can add sodium hydroxide alkalescence catalyzer.

5, by the preparation method of the said a kind of water-soluble high-molecular material of claim 1, it is characterized in that, said step 1. in, use the N in the acrylic amide, N dimethylamine base propyl group acrylamide.

6,, it is characterized in that the polymeric reaction temperature that said step is carried out in 2. is 20-75 ℃ by the preparation method of the said a kind of water-soluble high-molecular material of claim 1 under protection of inert gas.