阅读说明：本技术 一种非保护胶体系的改性叔醋乳液及其制备方法 (Modified tertiary vinegar emulsion of non-protective adhesive system and preparation method thereof ) 是由 李增辉 于 2021-09-10 设计创作，主要内容包括：本发明属于建筑材料领域,具体涉及一种非保护胶体系的改性叔醋乳液及其制备方法,该乳液包括质量分数的组分：表面活性剂0.4-1.2％、醋酸乙烯单体30.8-39.8％、叔碳酸乙烯4.3-5.6％、丙烯酸酯类单体6.5-8.5％、交联单体0.3-0.6％、功能单体1-2％、氧化还原引发剂0.4-0.6％、缓冲剂0.05-0.1％、余量为水。本发明采用半连续预乳化聚合工艺,并辅以氧化还原反应体系,提升了聚合过程中乳液的稳定性。本发明以丙烯酸酯类单体、叔碳酸乙烯酯以及特殊交联单体和功能单体对醋酸乙烯进行改性,所得到的乳液的耐水性,柔韧性和耐化学性能都有了显著提升,并且本发明使乳液的制备过程更加稳定,减少了残渣的产生,转化率也有所提高。(The invention belongs to the field of building materials, and particularly relates to a modified tertiary vinegar emulsion of a non-protective adhesive system and a preparation method thereof, wherein the emulsion comprises the following components in percentage by mass: 0.4-1.2% of surfactant, 30.8-39.8% of vinyl acetate monomer, 4.3-5.6% of tertiary ethylene carbonate, 6.5-8.5% of acrylate monomer, 0.3-0.6% of crosslinking monomer, 1-2% of functional monomer, 0.4-0.6% of redox initiator, 0.05-0.1% of buffering agent and the balance of water. The invention adopts a semi-continuous pre-emulsification polymerization process and is assisted by an oxidation-reduction reaction system, thereby improving the stability of the emulsion in the polymerization process. According to the invention, the acrylic ester monomer, the vinyl versatate, the special crosslinking monomer and the functional monomer are used for modifying the vinyl acetate, so that the water resistance, the flexibility and the chemical resistance of the obtained emulsion are remarkably improved, the preparation process of the emulsion is more stable, the generation of residues is reduced, and the conversion rate is also improved.)

1. A modified tertiary vinegar emulsion of a non-protective adhesive system is characterized in that: the emulsion is prepared from the following raw materials: 0.4-1.2% of surfactant, 30.8-39.8% of vinyl acetate monomer, 4.3-5.6% of tertiary ethylene carbonate, 6.5-8.5% of acrylate monomer, 0.3-0.6% of crosslinking monomer, 1-2% of functional monomer, 0.4-0.6% of redox initiator, 0.05-0.1% of buffering agent and the balance of water.

2. The modified tertiary-vinegar emulsion of non-protective gum system as claimed in claim 1, wherein: the surfactant is a mixture of a reactive emulsifier and a nonionic emulsifier, and the mass ratio of the reactive emulsifier to the nonionic emulsifier is 1-1.2: 1.

3. the modified tertiary-vinegar emulsion of non-protective gum system as claimed in claim 2, wherein: the reactive emulsifier is one or a mixture of more than two of alkyl allyl succinate sodium sulfonate, vinyl alkyl ester sodium sulfonate, allyl hydroxypropyl sodium sulfonate and allyloxy fatty alcohol vinyl ether ammonium sulfate.

4. The modified tertiary-vinegar emulsion of non-protective gum system as claimed in claim 2, wherein: the nonionic emulsifier is one of isomeric tridecanol and alkylphenol polyoxyethylene.

5. The modified tertiary-vinegar emulsion of non-protective gum system as claimed in claim 1, wherein: the acrylate monomer is one of butyl acrylate and isooctyl acrylate.

6. The modified tertiary-vinegar emulsion of non-protective gum system as claimed in claim 1, wherein: the crosslinking monomer is one of diallyl phthalate and 2-methyl-3 ethyl-oxybutyrate.

7. The modified tertiary-vinegar emulsion of non-protective gum system as claimed in claim 1, wherein: the functional monomer is one of acrylamide, acrylic acid or methacrylic acid.

8. The modified tertiary-vinegar emulsion of non-protective gum system as claimed in claim 1, wherein: the redox initiator is any one of ammonium persulfate/sodium bisulfite, potassium persulfate/sodium bisulfite and sodium persulfate/sodium bisulfite.

9. The modified tertiary-vinegar emulsion of non-protective gum system as claimed in claim 1, wherein: the buffer is sodium bicarbonate.

10. The modified tertiary-vinegar emulsion of non-protective gum system as claimed in claim 1, wherein: the preparation method comprises the following steps:

firstly, adding a surfactant accounting for 80% of the formula amount and a proper amount of water into a flask, quickly and uniformly stirring, then adding butyl acrylate, vinyl versatate, vinyl acetate, a crosslinking monomer and a functional monomer, and quickly stirring for 30-40 minutes to prepare a pre-emulsion for later use;

step two, adding a proper amount of water into the redox initiator in the formula respectively to prepare an oxidant aqueous solution and a reducing agent aqueous solution for later use;

adding 20% of surfactant and the balance of water into a reaction bottle, heating to 68 ℃, adding 5% of pre-emulsion, 1/4 of oxidant aqueous solution and 1/4 of reducing agent aqueous solution after the temperature is stable, reacting for 20 minutes, preparing seed emulsion, dropwise adding the rest of pre-emulsion and redox initiator aqueous solution, controlling the time to be 4 hours, controlling the temperature to be 69-71 ℃, and preserving the heat for 1 hour after the dropwise adding is finished;

and step four, finishing heat preservation, cooling to below 45 ℃, and adding a proper amount of defoaming agent and bactericide to obtain the modified tertiary vinegar emulsion of the non-protective adhesive system.

Technical Field

The invention belongs to the field of building materials, and particularly relates to a modified tertiary vinegar emulsion of a non-protective adhesive system and a preparation method thereof.

Background

In the field of building materials, most of the commonly used polyvinyl acetate emulsions are produced by using polyvinyl alcohol or hydroxyethyl cellulose as a protective adhesive, because the protective adhesive not only provides the stability of the emulsion, but also provides the hiding power and thixotropic property of downstream products. Therefore, the colloid protection polymerization process is the first choice process of the polyvinyl acetate emulsion, but the emulsion produced by the process has the characteristic of large particle size, so that the addition of the pigment and the filler of downstream products is negatively influenced. And the addition of polyvinyl alcohol leads the emulsion to have poor water resistance after film formation.

Disclosure of Invention

The invention provides a modified tertiary vinegar emulsion of a non-protective adhesive system and a preparation method thereof, and a polymerizable reactive emulsifier is adopted under a semi-continuous seed polymerization process and a pre-emulsification process, so that the reaction activity of vinyl acetate is improved, and the conversion rate of vinyl acetate monomers is greatly improved, so that the prepared emulsion solves the problems in the background art.

In order to achieve the purpose, the invention provides the following technical scheme: a modified tertiary vinegar emulsion of a non-protective adhesive system is prepared from the following raw materials: 0.4-1.2% of surfactant, 30.8-39.8% of vinyl acetate monomer, 4.3-5.6% of tertiary ethylene carbonate, 6.5-8.5% of acrylate monomer, 0.3-0.6% of crosslinking monomer, 1-2% of functional monomer, 0.4-0.6% of redox initiator, 0.05-0.1% of buffering agent and the balance of water.

Preferably, the surfactant is a mixture of a reactive emulsifier and a nonionic emulsifier, and the mass ratio of the reactive emulsifier to the nonionic emulsifier is 1-1.2: 1.

preferably, the reactive emulsifier is one or a mixture of more than two of alkyl allyl succinate sodium sulfonate, vinyl alkyl ester sodium sulfonate, allyl hydroxypropyl sodium sulfonate and allyloxy fatty alcohol vinyl ether ammonium sulfate.

Preferably, the nonionic emulsifier is one of isomeric tridecanol and alkylphenol polyoxyethylene.

Preferably, the acrylate monomer is one of butyl acrylate and isooctyl acrylate.

Preferably, the crosslinking monomer is one of diallyl phthalate and 2-methyl-3 ethyl-oxybutyrate.

Preferably, the functional monomer is one of acrylamide, acrylic acid or methacrylic acid.

Preferably, the redox initiator is any one of ammonium persulfate/sodium bisulfite, potassium persulfate/sodium bisulfite, and sodium persulfate/sodium bisulfite.

Preferably, the buffer is sodium bicarbonate.

Preferably, the preparation method of the modified tertiary vinegar emulsion of the non-protective glue system comprises the following steps:

firstly, adding a surfactant accounting for 80% of the formula amount and a proper amount of water into a flask, quickly and uniformly stirring, then adding butyl acrylate, vinyl versatate, vinyl acetate, a crosslinking monomer and a functional monomer, and quickly stirring for 30-40 minutes to prepare a pre-emulsion for later use;

step two, adding a proper amount of water into the redox initiator in the formula respectively to prepare an oxidant aqueous solution and a reducing agent aqueous solution for later use;

adding 20% of surfactant and the balance of water into a reaction bottle, heating to 68 ℃, adding 5% of pre-emulsion, 1/4 of oxidant aqueous solution and 1/4 of reducing agent aqueous solution after the temperature is stable, reacting for 20 minutes, preparing seed emulsion, dropwise adding the rest of pre-emulsion and redox initiator aqueous solution, controlling the time to be 4 hours, controlling the temperature to be 69-71 ℃, and preserving the heat for 1 hour after the dropwise adding is finished;

and step four, finishing heat preservation, cooling to below 45 ℃, and adding a proper amount of defoaming agent and bactericide to obtain the modified tertiary vinegar emulsion of the non-protective adhesive system.

The invention has the beneficial effects that: the modified tertiary vinegar emulsion of the non-protective glue system stabilizes the emulsion through the reactive emulsifier and the nonionic emulsifier, abandons the polyvinyl alcohol of the conventional method, adopts the semi-continuous pre-emulsification process, and has positive influence on the polymerization of the emulsion through the application of the oxidation-reduction reaction system. And the addition of special crosslinking monomers is utilized to establish crosslinking points of the emulsion, so that the compactness of the formed film of the emulsion is improved, and the addition of the vinyl versatate utilizes the ester group tight grafting of the highly branched functional group of the vinyl versatate to the vinyl acetate to greatly improve the water resistance of the emulsion, so that the application range of the emulsion is also improved, and the emulsion can be applied to inorganic heat-insulating paste materials and building coatings.

Detailed Description

The technical solutions of the present invention are described clearly and completely below, and it is obvious that the described embodiments are only a part of the embodiments of the present invention, not all of the embodiments. All other embodiments, which can be derived by a person skilled in the art from the embodiments given herein without making any creative effort, shall fall within the protection scope of the present invention.

Example 1:

3.5g of sodium alkyl allyl succinate sulfonate, 3.5g of isomeric tridecanol ether, 1g of allyloxy fatty alcohol vinyl ether ammonium sulfate, 4.8g of diallyl phthalate, 11g of acrylamide, 4.3g of acrylic acid, 71.4g of butyl acrylate, 48.5g of vinyl versatate, 365.4g of vinyl acetate, 2.8g of ammonium persulfate, 2.7g of sodium bisulfite, 490.5g of deionized water, 1.5g of defoaming agent and 1.5g of bactericide.

The reaction process is as follows:

(1) 3.5g of alkyl allyl succinate sodium sulfonate, 2.5g of isomeric tridecanol ether and 120g of deionized water are added into a flask and quickly and uniformly stirred, then butyl acrylate, vinyl versatate, vinyl acetate, a crosslinking monomer and a functional monomer are added, and the mixture is quickly stirred for 30 to 40 minutes to prepare a pre-emulsion for later use.

(2) 2.8g of oxidant is added into 50g of water to prepare an oxidant aqueous solution for standby.

(3) 2.7g of reducing agent is added into 50g of water to prepare a reducing agent aqueous solution for standby.

(4) 1g of allyloxy fatty alcohol vinyl ether ammonium sulfate, 3.5g of isomeric tridecanol ether and 270.5g of water are added into a reaction bottle, the temperature is raised to 68 ℃, after the temperature is stabilized, 5% of pre-emulsion, 1/4 of oxidant aqueous solution and 1/4 of reducing agent aqueous solution are added, after 20 minutes of reaction, seed emulsion is prepared, the rest of pre-emulsion and redox initiator aqueous solution are dropwise added, the time is controlled to be 4 hours, the temperature is controlled to be 69-71 ℃, and after the dropwise addition is finished, the temperature is kept for 1 hour.

(5) And (3) after the heat preservation is finished, cooling to below 45 ℃, and adding 1.5g of defoaming agent and 1.5g of bactericide to obtain the modified tertiary vinegar emulsion of the non-protective adhesive system.

Example 2:

4g of sodium allylhydroxypropyl sulfonate, 3g of isomeric tridecanol ether, 1g of allyloxy fatty alcohol vinyl ether ammonium sulfate, 4.8g of 2-methyl-3 ethyl-oxybutyrate ester, 11g of acrylamide, 4.3g of methacrylic acid, 51.4g of butyl acrylate, 58.5g of vinyl versatate, 375.4g of vinyl acetate, 2.8g of ammonium persulfate, 2.7g of sodium bisulfite, 490.5g of deionized water, 1.5g of defoaming agent and 1.5g of bactericide.

The reaction process is as follows:

(1) 4g of sodium allylhydroxypropyl sulfonate, 1.5g of isomeric tridecanol ether and 120g of deionized water are added into a flask and quickly and uniformly stirred, then butyl acrylate, vinyl versatate, vinyl acetate, crosslinking monomer and functional monomer are added and quickly stirred for 30-40 minutes to prepare pre-emulsion for later use.

(2) 2.8g of oxidant is added into 50g of water to prepare an oxidant aqueous solution for standby.

(3) 2.7g of reducing agent is added into 50g of water to prepare a reducing agent aqueous solution for standby.

(4) Adding 1g of allyloxy fatty alcohol vinyl ether ammonium sulfate, 1.5g of isomeric tridecanol ether and 270.5g of water into a reaction bottle, heating to 68 ℃, adding 5% of pre-emulsion, 1/4 of oxidant aqueous solution and 1/4 of reducing agent aqueous solution after the temperature is stable, reacting for 20 minutes, preparing seed emulsion, dropwise adding the rest of pre-emulsion and redox initiator aqueous solution, controlling the time to be 4 hours, controlling the temperature to be 69-71 ℃, and preserving the heat for 1 hour after the dropwise adding is finished.

(5) And (3) after the heat preservation is finished, cooling to below 45 ℃, and adding 1.5g of defoaming agent and 1.5g of bactericide to obtain the modified tertiary vinegar emulsion of the non-protective adhesive system.

Example 3:

5g of sodium vinyl alkyl ester sulfonate, 2g of alkylphenol polyoxyethylene, 1g of allyloxy fatty alcohol vinyl ether ammonium sulfate, 4.8g of diallyl phthalate, 8.5g of acrylamide, 7g of acrylic acid, 91.4g of butyl acrylate, 38.5g of vinyl versatate, 355.4g of vinyl acetate, 2.8g of ammonium persulfate, 2.7g of sodium bisulfite, 490.5g of deionized water, 1.5g of defoaming agent and 1.5g of bactericide.

The reaction process is as follows:

(1) 5g of sodium allylhydroxypropylsulfonate, 1g of alkylphenol polyoxyethylene and 120g of deionized water are added into a flask and quickly and uniformly stirred, then butyl acrylate, vinyl versatate, vinyl acetate, crosslinking monomer and functional monomer are added and quickly stirred for 30-40 minutes to prepare pre-emulsion for later use.

(2) 2.8g of oxidant is added into 50g of water to prepare an oxidant aqueous solution for standby.

(3) 2.7g of reducing agent is added into 50g of water to prepare a reducing agent aqueous solution for standby.

(4) Adding 1g of allyloxy fatty alcohol vinyl ether ammonium sulfate, 1g of alkylphenol ethoxylate and 270.5g of water into a reaction bottle, heating to 68 ℃, adding 5% of pre-emulsion, 1/4 of oxidant aqueous solution and 1/4 of reducing agent aqueous solution after the temperature is stable, reacting for 20 minutes, preparing seed emulsion, dropwise adding the rest of pre-emulsion and redox initiator aqueous solution, controlling the time to be 4 hours, controlling the temperature to be 69-71 ℃, and preserving the heat for 1 hour after the dropwise adding is finished.

(5) And (3) after the heat preservation is finished, cooling to below 45 ℃, and adding 1.5g of defoaming agent and 1.5g of bactericide to obtain the modified tertiary vinegar emulsion of the non-protective adhesive system.

Comparative example:

1.5g of alkylphenol polyoxyethylene, 30g of polyvinyl alcohol, 91.4g of butyl acrylate, 38.5g of vinyl versatate, 355.4g of vinyl acetate, 2.8g of ammonium persulfate, 2.7g of sodium bisulfite, 490.5g of deionized water, 1.5g of defoaming agent and 1.5g of bactericide.

The reaction process is as follows:

(1) 2.8g of oxidant is added into 50g of water to prepare an oxidant aqueous solution for standby.

(2) 2.7g of reducing agent is added into 50g of water to prepare a reducing agent aqueous solution for standby.

(3) Butyl acrylate, vinyl versatate, vinyl acetate and crosslinking monomer are added into a flask and uniformly stirred for later use.

(4) Adding the rest water and 30g of polyvinyl alcohol into a reaction bottle, stirring and heating to 90 ℃ to completely dissolve the polyvinyl alcohol, cooling to 65 ℃, adding 5% of premixed monomer solution, 1/4 of oxidant aqueous solution and 1/4 of reducing agent aqueous solution, reacting for 20 minutes, preparing seed emulsion, dropwise adding the rest premixed monomer solution and the redox initiator aqueous solution, controlling the time to be 4 hours, controlling the temperature to be 69-71 ℃, and preserving the heat for 1 hour after the dropwise adding is finished.

(5) After the heat preservation is finished, the temperature is reduced to below 45 ℃, and 1.5g of defoaming agent and 1.5g of bactericide are added

And (3) performance detection:

the emulsions of experiments 1-3 and comparative examples described above were tested for their properties as follows:

detecting items	Example 1	Example 2	Example 3	Comparative example
					Viscosity (MPa.S)	859	950	874	3447
Average particle diameter (nm)	118	121	125	340
					Water absorption (%)	10.4	12.3	12.4	43.4
pH value	4.5	4.3	4.6	4.7
					Residue (%)	0.15	0.2	0.14	0.3

As shown in the table, when the properties of examples 1 to 3 of the present invention and the comparative examples are compared, the particle size and viscosity of the emulsion are greatly reduced, and the water absorption of the emulsion is also reduced, which indicates that the water resistance of the emulsion is improved, and the residue rate is also significantly reduced compared to the comparative example, thereby showing that the stability of the emulsion is also improved.

The modified tertiary vinegar emulsion of the non-protective adhesive system stabilizes the emulsion through the reactive emulsifier and the nonionic emulsifier, abandons the polyvinyl alcohol of the conventional method, adopts the semi-continuous pre-emulsification process, and has positive influence on the polymerization of the emulsion through the application of the oxidation-reduction reaction system. And the addition of special crosslinking monomers is utilized to establish crosslinking points of the emulsion, so that the compactness of the formed film of the emulsion is improved, and the addition of the vinyl versatate utilizes the ester group tight grafting of the highly branched functional group of the vinyl versatate to the vinyl acetate to greatly improve the water resistance of the emulsion, so that the application range of the emulsion is also improved, and the emulsion can be applied to inorganic heat-insulating paste materials and building coatings.

The above description is only for the specific embodiments of the present invention, but the scope of the present invention is not limited thereto, and any person skilled in the art can easily conceive of the changes or substitutions within the technical scope of the present invention, and all the changes or substitutions should be covered within the scope of the present invention. Therefore, the protection scope of the present invention shall be subject to the protection scope of the claims.