Cationic polyacrylate waterproof agent dispersion and preparation method thereof

Abstract

The invention discloses a cationic polyacrylate waterproof agent dispersoid and a preparation method thereof, and belongs to the field of waterproof agent dispersoids, the preparation method comprises the following steps: S1, mixing glycidyl methacrylate and an acrylate monomer in a solvent for reaction to generate a first polymer, the first polymer is a polymer containing an epoxy group; s2, the first polymer and double-long-chain alkylamine are mixed, so that an epoxy group of the first polymer and secondary amino in the double-long-chain alkylamine are subjected to a ring-opening reaction, a second polymer is generated, and the molecular structure of the second polymer contains hydroxyl and amino; s3, mixing and reacting the second polymer and monocarboxyl silicone oil to generate a third polymer; S4, reacting the third polymer and organic acid to generate a mixture containing a fourth polymer; and S5, performing post-treatment on the mixture.

Description

Technical Field

[0001] The invention relates to the field of fine chemicals, in particular to a cationic polyacrylate waterproofing agent dispersion and a preparation method thereof. Background Art

[0002] The waterproof properties of textiles through waterproof finishing can greatly expand the application range of textiles. In the current printing and dyeing process, cationic fluorinated polyacrylate emulsions are widely used as waterproof agents for textiles. The perfluoroalkyl side chains with extremely low surface energy are enriched on the surface of the fabric, making the finished fabric show extremely low surface energy, thus achieving waterproof and even oil-proof properties.

[0003] With increasingly stringent environmental regulations, the use of fluorine-containing waterproofing agents will be restricted due to their potential harm to the environment and human health, and fluorine-free waterproofing agents will gradually become the mainstream choice in the market. Fluorine-free waterproofing agents do not contain fluorine and will not pollute the environment during use. Currently, the fluorine-free waterproofing agents on the market are mainly cationic polyacrylate emulsions. During the preparation process of such products, silicone with low surface energy and long-chain alkyl (meth) acrylates are generally added to copolymerize with acrylate monomers. The synergistic effect of silicone and long-chain alkyl enables such products to achieve good waterproof performance; silicone with low surface energy is the main raw material for preparing fluorine-free waterproofing agents, but in traditional emulsion polymerization, long-chain organosiloxanes (silicone oils) are difficult to copolymerize to the molecular chain, and are often used in products in the form of compounding, so a large amount of emulsifiers are needed to emulsify the silicone oil to ensure stability. However, even so, there are problems with the stability of such products during storage, and the silicone oil is very easy to precipitate and float on the surface. In addition, the preparation process of such products is the same as the traditional emulsion polymerization process. Generally, cationic emulsifiers are added to provide stability, and hydrophilic initiators are used as initiators for the polymerization reaction. Therefore, the large-scale use of small molecule emulsifiers in such products can easily lead to a large amount of foam generated during the use of such products, which brings great inconvenience to production. At the same time, it is easy to form foam spots on the cloth surface, affecting the quality of the finished cloth; at the same time, the emulsifier is easy to migrate to the air interface during the film formation process, thereby enriching on the film-forming surface, which enhances the hydrophilicity of the film-forming surface. In addition, the use of hydrophilic initiators also makes the molecular chain contain more hydrophilic groups. The combined effect of the two will greatly affect the actual application effect of the waterproofing agent. In view of the above problems, the market urgently needs to improve the existing fluorine-free cationic polyacrylate waterproofing agent system to overcome the existing defects. Summary of the invention

[0004] The purpose of the present invention is to solve the problems in the prior art and disclose a method for preparing a cationic polyacrylate waterproofing agent dispersion, the steps of which are as follows:

[0005] S1: mixing glycidyl methacrylate and acrylate monomers in a solvent to generate a first polymer, wherein the first polymer is a polymer containing an epoxy group;

[0006] S2: mixing the first polymer and the di-long chain alkylamine, so that the epoxy group of the first polymer and the secondary amino group in the di-long chain alkylamine undergo a ring-opening reaction to generate a second polymer, wherein the molecular structure of the second polymer contains a hydroxyl group and an amino group;

[0007] S3: The second polymer and the monocarboxyl silicone oil are mixed and reacted to generate a third polymer

[0008] S4: reacting the third polymer with the organic acid to generate a mixture containing the fourth polymer;

[0009] S5: post-processing the mixture.

[0010] In the improved solution, the acrylic acid ester monomer is butyl acrylate, and the solvent is diethylene glycol butyl ether.

[0011] In the improved scheme, step S1 is: add butyl diglycol into a container, dropwise add a monomer mixture and an initiator solution, the monomer mixture is a mixture of glycidyl methacrylate, styrene and butyl acrylate, and the initiator solution is obtained by dissolving benzoyl peroxide in butyl diglycol.

[0012] In the improved scheme, the di-long-chain alkylamine is ditetradecylamine.

[0013] In the improved solution, the monocarboxyl silicone oil is BY16-880.

[0014] In an improved solution, the organic acid is formic acid, acetic acid, propionic acid or a mixture of several thereof.

[0015] In the improved scheme, step S3 is: adding BY16-880 into a container containing the second polymer and stirring the mixture for reaction.

[0016] In the improved scheme, step S2 is: lowering the temperature of the mixture containing the first polymer to 80° C., slowly adding ditetradecylamine, and then keeping the temperature to react.

[0017] In the improved solution, the steps of post-processing the mixture are: adding ionized water and high-speed emulsification and dispersion.

[0018] The application also discloses a cationic polyacrylate waterproofing agent dispersion, which is prepared by the method described.

[0019] The present invention utilizes copolymerization of glycidyl methacrylate and other acrylate monomers to introduce epoxy groups into the polymer molecular chain, and then utilizes the ring-opening reaction of the epoxy groups with the secondary amino groups in the di-long chain alkylamine to generate a tertiary amine structure while also introducing a hydrophobic long-chain alkyl group into the molecular structure of the polymer (e.g. Figure 1 As shown), in addition, the generated hydroxyl group can be used as a reactive group for subsequent curing and cross-linking, and can be fixed on the fabric under the action of an externally added cross-linking agent, thereby meeting the washing fastness requirements of the waterproofing agent application; then add monocarboxyl silicone oil, and use the salt-forming reaction of the carboxyl silicone oil and the amino group to fix the long-chain siloxane on the polymer molecular chain through ionic bonds; finally, add a small molecule organic acid to neutralize the remaining amino group, generate a quaternary ammonium salt structure on the molecular chain, and give it cationicity while ensuring that the product is soluble in water.

[0020] In traditional silicone-modified polyacrylate waterproofing agents, silicone oil is basically dispersed in the system by emulsification and compounding. The monocarboxyl silicone oil used in the present invention reacts with the amino group on the polymer molecular chain to form a salt, and the long-chain polysiloxane is fixed on the polyacrylate molecular chain through an ionic bond, so the stability is stronger. Unlike conventional cationic waterproofing agent emulsions that need to add a large amount of cationic and non-ionic emulsifiers during the preparation process, the cationic acrylic waterproofing agent dispersion prepared by the present invention does not use small molecule emulsifiers during the preparation process. It utilizes acid to neutralize the tertiary amino group on the polymer molecular chain to form an ionizable quaternary ammonium salt, which, while imparting cationicity, also ensures that it can be stably dispersed in water. Therefore, the cationic waterproofing agent dispersion prepared by the present invention basically eliminates the foam problem caused by the introduction of a large amount of emulsifiers in the use of conventional waterproofing agent emulsions, and also avoids the negative impact of small molecule emulsifiers on the membrane surface enrichment and the waterproof effect to a certain extent. BRIEF DESCRIPTION OF THE DRAWINGS

[0021] Figure 1 This is a schematic diagram of the ring-opening reaction. DETAILED DESCRIPTION

[0022] The present invention is described in detail below by way of examples. It is necessary to point out that the examples are only used to further illustrate the present invention and cannot be understood as limiting the scope of protection of the present invention. Some non-essential improvements and adjustments made by persons skilled in the art based on the above-mentioned contents of the present invention should all fall within the scope of protection of the present invention. Therefore, the scope of protection of the present invention should be subject to the scope of protection of the claims.

[0023] Embodiment 1:

[0024] Add 20g of diethylene glycol butyl ether to a four-necked flask equipped with a thermometer, a stirrer, a condenser and a monomer dropping device, start the stirring and heating device, and pass nitrogen protection. Raise the temperature to 120°C, and drop the monomer mixture and initiator solution respectively. The monomer mixture is a mixture of 7g of glycidyl methacrylate, 18g of styrene and 25g of butyl acrylate, and the initiator solution is 0.2g of benzoyl peroxide dissolved in 1g of diethylene glycol butyl ether. The dropping time is controlled at 4h. After the dropping is completed, 0.1g of benzoyl peroxide is dissolved in 0.5g of diethylene glycol butyl ether as a post-elimination initiator, added to the system and kept warm for reaction for 1h. After the insulation is completed, the reaction temperature is lowered to 80°C, and 20g of ditetradecylamine is slowly added within 1h, and then kept warm for reaction for 2h. While maintaining the temperature, first add 8g BY16-880 and stir to react for 30 minutes, then add 2.0g formic acid and stir thoroughly for 30 minutes; then lower the material temperature to 70°C, add 200g ionized water, emulsify and disperse at high speed for 30 minutes, filter after dispersion to obtain a cationic polyacrylate waterproofing agent dispersion.

[0025] Embodiment 2:

[0026] Add 20g of dipropylene glycol butyl ether to a four-necked flask equipped with a thermometer, a stirrer, a condenser and a monomer dropping device, start the stirring and heating device, and pass nitrogen protection. Raise the temperature to 130°C, and drop the monomer mixture and initiator solution respectively. The monomer mixture is a mixture of 10g of glycidyl methacrylate, 20g of styrene and 20g of butyl acrylate, and the initiator solution is 0.2g of benzoyl peroxide dissolved in 1g of dipropylene glycol butyl ether. The dropping time is controlled at 4h. After the dropping is completed, 0.1g of benzoyl peroxide is dissolved in 0.5g of dipropylene glycol butyl ether as a post-elimination initiator, added to the system and kept warm for reaction for 1h. After the insulation is completed, the reaction temperature is lowered to 80°C, and 30g of dihexadecylamine is slowly added within 1h, and then kept warm for reaction for 2h. While maintaining the temperature, first add 9g BY16-880 and stir to react for 30 minutes, then add 3.3g acetic acid and stir thoroughly for 30 minutes; then lower the material temperature to 70°C, add 250g ionized water, emulsify and disperse at high speed for 30 minutes, filter after dispersion to obtain a cationic polyacrylate waterproofing agent dispersion.

[0027] Embodiment 3:

[0028] Add 20g of propylene glycol methyl ether to a four-necked flask equipped with a thermometer, a stirrer, a condenser and a monomer dropping device, start the stirring and heating device, and pass nitrogen protection. Raise the temperature to 130°C, and drop the monomer mixture and initiator solution respectively. The monomer mixture is a mixture of 8g of glycidyl methacrylate, 20g of styrene and 21g of butyl acrylate, and the initiator solution is 0.2g of benzoyl peroxide dissolved in 1g of propylene glycol methyl ether. The dropping time is controlled at 4h. After the dropping is completed, 0.1g of benzoyl peroxide is dissolved in 0.5g of propylene glycol methyl ether as a post-elimination initiator, added to the system and kept warm for reaction for 1h. After the insulation is completed, the reaction temperature is lowered to 80°C, and 25g of dioctadecylamine is slowly added within 1h, and then kept warm for reaction for 2h. While maintaining the temperature, first add 8g BY16-880 and stir to react for 30 minutes, then add 2.5g acetic acid and stir thoroughly for 30 minutes; then lower the material temperature to 70°C, add 240g ionized water, emulsify and disperse at high speed for 30 minutes, filter after dispersion to obtain a cationic polyacrylate waterproofing agent dispersion.

[0029] Embodiment 4:

[0030] Add 20g of ethylene glycol butyl ether to a four-necked flask equipped with a thermometer, a stirrer, a condenser and a monomer dropping device, start the stirring and heating device, and pass nitrogen protection. Raise the temperature to 130°C, and drop the monomer mixture and initiator solution respectively. The monomer mixture is a mixture of 9g of glycidyl methacrylate, 21g of styrene and 20g of butyl acrylate, and the initiator solution is 0.2g of benzoyl peroxide dissolved in 1g of ethylene glycol butyl ether. The dropping time is controlled at 4h. After the dropping is completed, 0.1g of benzoyl peroxide is dissolved in 0.5g of ethylene glycol butyl ether as a post-elimination initiator, added to the system and kept warm for reaction for another 1h. After the insulation is completed, the reaction temperature is lowered to 80°C, and a mixture of 15g of dioctadecylamine and 15g of dihexadecylamine is slowly added within 1h, and then kept warm for reaction for another 2h. While maintaining the temperature, first add 9g BY16-880 and stir to react for 30 minutes, then add 3g acetic acid and stir thoroughly for 30 minutes; then lower the material temperature to 70°C, add 270g ionized water, emulsify and disperse at high speed for 30 minutes, filter after dispersion to obtain a cationic polyacrylate waterproofing agent dispersion.

[0031] Performance Testing:

[0032] (1) Determination of the zeta potential of the dispersion: The above Examples 1-4 were diluted with deionized water to an effective solid content of 1%, and then measured using a Zetasizer Nano S90 laser particle size-potential analyzer. The results are shown in Table 1:

[0033] Table 1 ξ potential measurement results of the examples

[0034] sample Example 1 Example 2 Example 3 Example 4 Zeta potential 25.35mv 29.45mv 26.42mv 27.78mv

[0035] The results show that the zeta potentials of Examples 1 to 4 are all positive, indicating that they are all cationic dispersions.

[0036] (2) Determination of waterproof performance: The above Examples 1-4 were diluted with deionized water to an effective solid content of 1%, and then the padding process was carried out using 80, specifically: one dip and one padding (pressure 2 kg / cm 2 )→Drying (100℃)→Bake in a setting machine (pure cotton: 160℃x1.5 min; polyester cotton 180℃x 1.5min)→Test the waterproof effect after moisture regain. Waterproof grade test according to GB / T 4745-1997 standard:

[0037] Level 0: Both sides of the fabric are wetted

[0038] Level 1: Almost all of the front side is wetted

[0039] Level 2: More than half of the positive surface is wetted

[0040] Level 3: Only a small amount of discontinuous parts on the front are wetted Level 4: The front is not wetted but a small amount of droplets adhere to it Level 5: The front is not wetted and no droplets adhere to it Example Waterproof Performance Test Results:

[0041] 65 / 35 polyester-cotton woven fabric Cotton gauze cloth Example 1 Level 3-4 Level 3-4 Example 2 Level 4 Level 4 Example 3 Level 4-5 Level 4-5 Example 4 Level 4 Level 4 .

Claims

1. A method for preparing a cationic polyacrylate waterproofing agent dispersion, characterized in that: Here are the steps: S1: mixing glycidyl methacrylate and acrylate monomers in a solvent to generate a first polymer, wherein the first polymer is a polymer containing an epoxy group; S2: mixing the first polymer and the di-long chain alkylamine, so that the epoxy group of the first polymer and the secondary amino group in the di-long chain alkylamine undergo a ring-opening reaction to generate a second polymer, wherein the molecular structure of the second polymer contains a hydroxyl group and an amino group; S3: The second polymer and the monocarboxyl silicone oil are mixed and reacted to generate a third polymer S4: reacting the third polymer with the organic acid to generate a mixture containing the fourth polymer; S5: post-processing the mixture.

2. The method for preparing a cationic polyacrylate waterproofing agent dispersion according to claim 1, characterized in that: The acrylic acid ester monomer is butyl acrylate, and the solvent is diethylene glycol butyl ether.

3. The method for preparing a cationic polyacrylate waterproofing agent dispersion according to claim 2, characterized in that: Step S1 is: adding butyl diglycol into a container, and dropping a monomer mixture and an initiator solution, wherein the monomer mixture is a mixture of glycidyl methacrylate, styrene and butyl acrylate, and the initiator solution is obtained by dissolving benzoyl peroxide in butyl diglycol.

4. The method for preparing a cationic polyacrylate waterproofing agent dispersion according to claim 1, characterized in that: The di-long-chain alkylamine is ditetradecylamine.

5. The method for preparing a cationic polyacrylate waterproofing agent dispersion according to claim 1, characterized in that: The monocarboxyl silicone oil is BY16-880.

6. The method for preparing a cationic polyacrylate waterproofing agent dispersion according to claim 1, characterized in that: The organic acid is one or a mixture of formic acid, acetic acid and propionic acid.

7. The method for preparing a cationic polyacrylate waterproofing agent dispersion according to claim 6, characterized in that: Step S3 is: adding BY16-880 into a container containing the second polymer and stirring for reaction.

8. The method for preparing a cationic polyacrylate waterproofing agent dispersion according to claim 8, characterized in that: Step S2 is: lowering the temperature of the mixture containing the first polymer to 80° C., slowly adding ditetradecylamine, and then keeping the temperature to react.

9. The method for preparing a cationic polyacrylate waterproofing agent dispersion according to claim 8, characterized in that: The steps of post-processing the mixture are: adding ionized water and high-speed emulsification and dispersion.

10. A cationic polyacrylate waterproofing agent dispersion, characterized in that: Prepared by the method described in any one of claims 1 to 9.

Images