阅读说明：本技术 一种asa高胶粉的制备方法 (Preparation method of ASA high-glue powder ) 是由 刘伯军 胡艺伟 刘香池 张明耀 王佰佳 罗雪妍 刘孟恩 汤千熠 杜宇航 吴高澄 于 2021-08-24 设计创作，主要内容包括：本发明公开了一种ASA高胶粉的制备方法,属于合成树脂领域。本发明采用反应型乳化剂即含有不饱和双键的硫酸盐或磺酸盐为乳化剂直接将乳化剂分子作为功能单体直接聚合在丙烯酸酯橡胶上,并且通过喷雾干燥的方式进行絮凝干燥。制备ASA高胶粉所含有的吸附型乳化剂含量为零,进而提升了ASA高胶粉的颜色耐热稳定性,使其长时间高温条件下白度保留值高,易用来制备对颜色和光泽要求较高的制品。(The invention discloses a preparation method of ASA high-glue powder, belonging to the field of synthetic resin. The invention adopts a reactive emulsifier, namely sulfate or sulfonate containing unsaturated double bonds as an emulsifier to directly polymerize emulsifier molecules as functional monomers on acrylate rubber, and performs flocculation drying in a spray drying mode. The adsorption emulsifier content in the prepared ASA high-glue powder is zero, so that the color heat-resistant stability of the ASA high-glue powder is improved, the whiteness retention value of the ASA high-glue powder is high under the long-time high-temperature condition, and the ASA high-glue powder is easy to prepare products with high requirements on color and gloss.)

1. A preparation method of ASA high-glue powder is characterized by comprising the following steps:

(1) putting 1-5 parts of reactive emulsifier, 0.1-3 parts of electrolyte and 0.1-2 parts of initiator I into a reaction kettle in parts by mass, adding 40-70 parts of deionized water, and stirring until the materials are completely dissolved;

(2) adding 5-30 parts of acrylate monomer, 0.1-3 parts of cross-linking agent and 0.1-3 parts of grafting agent into the reaction kettle in the step (1) by mass part, heating the mixture to 50-85 ℃ in a nitrogen environment, and reacting for 0.5-2 h;

(3) dropping 30-60 parts of acrylate monomer, 0.1-3 parts of cross-linking agent and 0.1-3 parts of grafting agent into the reaction kettle in the step (2) by mass for 1-5 hours, and keeping the temperature at 85 ℃ for 0.5-2 hours after dropping to obtain polyacrylate latex, and diluting the polyacrylate latex with deionized water until the solid content is 30%;

(4) taking 100 parts by mass of the diluted polyacrylate latex obtained in the step (3), placing the diluted polyacrylate latex in a grafting reaction kettle, adding 0.1-1 part by mass of an initiator II, 0.1-1 part by mass of a chelating agent, 0.01-1 part by mass of a co-reducing agent and 0.001-0.1 part by mass of a reducing agent, heating the mixture to 40-75 ℃ in a nitrogen environment, dropwise adding 15-30 parts by mass of a styrene monomer, 5-10 parts by mass of an acrylonitrile monomer and 0.01-1 part by mass of the initiator II for 1-6 hours, heating the mixture to 85 ℃ after the dropwise adding is finished, and keeping the temperature for 0.5-1 hour to obtain ASA latex;

(5) and (4) drying the latex obtained in the step (4) to obtain the ASA high-glue powder.

2. The method for preparing ASA high-glue powder according to claim 1, wherein the reactive emulsifier in step (1) is one or more selected from acrylamide isopropyl sodium sulfonate, sodium vinyl sulfonate, 2-propyl ether 3-hydroxy propane-1-sodium sulfonate, allyl ether hydroxy propane sodium sulfonate, allyl polyether sulfate, alkyl phenol allyl polyether sulfate, and allyl alcohol ether-containing sulfate.

3. The method for preparing ASA high-glue powder according to claim 1, wherein the electrolyte in step (1) is one or more of potassium carbonate, sodium carbonate, potassium bicarbonate, sodium chloride, sodium sulfate, and potassium sulfate.

4. The method for preparing ASA high-glue powder according to claim 1, wherein the initiator I in step (1) is one or more of potassium persulfate, ammonium persulfate and sodium persulfate.

5. The method for preparing ASA high-glue powder according to claim 1, wherein the acrylate monomer in step (2) and step (3) is one or more of butyl acrylate, butyl methacrylate, isooctyl acrylate and ethyl acrylate; one or more of divinylbenzene, ethylene glycol dimethacrylate, triallyl isocyanurate and dicyclopentenyl acrylate as the crosslinking agent are mixed; the grafting agent is one or a mixture of allyl methacrylate and allyl acrylate.

6. The method for preparing ASA high-adhesive powder according to claim 1, wherein the initiator II in the step (4) is cumene hydroperoxide; the chelating agent is one of sodium pyrophosphate or disodium ethylene diamine tetraacetate; the auxiliary reducing agent is one of fructose, glucose and sodium formaldehyde sulfoxylate; the reducing agent is ferrous sulfate.

7. The process for preparing ASA high-adhesive powder according to claim 1, wherein the drying in step (5) is spray drying or flocculation precipitation drying.

8. A process for preparing ASA high-gum powder according to claim 7, wherein the spray drying is air or nitrogen spray drying.

9. The method for preparing ASA high-glue powder according to claim 7, wherein the flocculating agent in the flocculation precipitation drying is one or more of sulfuric acid, magnesium sulfate, calcium chloride, potassium chloride and sodium chloride.

Technical Field

The invention relates to the technical field of synthetic resin, in particular to a preparation method of ASA high-rubber powder.

Background

The ASA high-glue powder is a plastic modifier with rubber content of 40-70% obtained by grafting a layer of styrene and acrylonitrile copolymer (SAN) on the surface of polyacrylate latex through emulsion grafting reaction and then flocculating and drying. The ASA high-glue powder can be blended with engineering plastics to form alloy so as to improve the toughness of the plastics, for example, the most common ASA resin is a product obtained by melt blending the ASA high-glue powder and SAN resin. The common composite materials prepared by ASA high-glue powder also comprise PC/ASA alloy, PVC/ASA alloy, PBT/ASA alloy and the like. The core technology for preparing the ASA high-adhesive powder comprises the following two steps: firstly, a preparation process of core layer latex polyacrylate latex; the second is surface grafting of polyacrylate latex. In recent years, there are many patents and articles disclosing processes for preparing ASA powder. For example, CN 104231185A adopts adsorptive anionic surfactants such as alkyl sulfate, alkyl sulfonate or alkyl benzene sulfonate as emulsifiers to prepare small-particle-size polyacrylate latex, then ASA latex with particle size of 160-170nm is prepared by emulsion graft polymerization, and then ASA high-rubber powder is obtained by flocculation demulsification and drying; in patent CN 109293842A, anionic and nonionic mixed emulsifiers are adopted to prepare polyacrylate latex, and then the polyacrylate latex is subjected to flocculation drying to prepare ASA resin high-gel powder; in patent CN 109651571A, acrylate modified polyurethane is used as initial seed latex, then polyacrylate latex is prepared by using sodium dodecyl sulfate, sodium dodecyl sulfate and sodium dodecyl benzene sulfonate as anionic emulsifiers based on the seed latex by using a diameter expanding method, ASA latex with the particle size of 150-230nm is prepared by grafting, ASA high-rubber powder is obtained after flocculation drying, and high-impact ASA resin is obtained after mixing with SAN resin. The CN 109071737A patent adopts polyfunctional carboxylic acid with more than 20 carbon atoms or salt thereof as an emulsifier to prepare ASA high-rubber powder, thereby improving the whiteness of the ASA resin and reducing color difference.

Summarizing the preparation method of ASA high-adhesive powder disclosed at present, it can be seen that the emulsifiers used in the preparation process of ASA high-adhesive powder can be divided into several types: an adsorption type anionic emulsifier represented by sodium lauryl sulfate; one is a mixed emulsifier which takes adsorptive anionic emulsifier as the main part and takes nonionic emulsifier as the auxiliary part; one is a polyfunctional carboxylic acid having 20 or more carbon atoms or a salt thereof as an emulsifier. The emulsifier is in principle a small molecule, and the presence of the emulsifier directly affects the mechanical properties as well as the apparent properties of the material. In particular fields, the presence of emulsifiers also directly affects the surface gloss and the dyeing properties of the materials. Although the patent CN 109071737 a reports that the multifunctional carboxylic acid with more than 20 carbon atoms or the salt thereof is adopted as the emulsifier to solve the problems, the emulsifier is expensive and is added in a large amount in emulsion polymerization, which greatly increases the production cost of ASA high-adhesive powder.

Therefore, the problem to be solved by those skilled in the art is how to provide a method for producing ASA high-adhesive powder with low cost and good performance.

Disclosure of Invention

In view of the above, the invention provides a preparation method of ASA high-glue powder, which is characterized in that a commercially produced sulfonate or sulfate type emulsifier containing vinyl is used as an emulsifier in the polymerization process of acrylate emulsion to prepare ASA emulsion, the particle size is regulated and controlled by electrolyte to directly prepare large-particle-size polyacrylate latex by one step, the ASA latex with the particle size of 250-700 nm can be finally obtained after emulsion grafting, and the ASA high-glue powder can be obtained after simple spray drying, and is high in toughening efficiency and good in whiteness.

In order to achieve the purpose, the invention adopts the following technical scheme:

a preparation method of ASA high-glue powder comprises the following steps:

(1) putting 1-5 parts of reactive emulsifier, 0.1-3 parts of electrolyte and 0.1-2 parts of initiator I into a reaction kettle in parts by mass, adding 40-70 parts of deionized water, and stirring until the materials are completely dissolved;

(2) adding 5-30 parts of acrylate monomer, 0.1-3 parts of cross-linking agent and 0.1-3 parts of grafting agent into the reaction kettle in the step (1) by mass part, heating the mixture to 50-85 ℃ in a nitrogen environment, and reacting for 0.5-2 h;

(3) dropping 30-60 parts of acrylate monomer, 0.1-3 parts of cross-linking agent and 0.1-3 parts of grafting agent into the reaction kettle in the step (2) by mass for 1-5 hours, and keeping the temperature at 85 ℃ for 0.5-2 hours after dropping to obtain polyacrylate latex, and diluting the polyacrylate latex with deionized water until the solid content is 30%;

(4) taking 100 parts by mass of the diluted polyacrylate latex obtained in the step (3), placing the diluted polyacrylate latex in a grafting reaction kettle, adding 0.1-1 part by mass of an initiator II, 0.1-1 part by mass of a chelating agent, 0.01-1 part by mass of a co-reducing agent and 0.001-0.1 part by mass of a reducing agent, heating the mixture to 40-75 ℃ in a nitrogen environment, dropwise adding 15-30 parts by mass of a styrene monomer, 5-10 parts by mass of an acrylonitrile monomer and 0.01-1 part by mass of the initiator II for 1-6 hours, heating the mixture to 85 ℃ after the dropwise adding is finished, and keeping the temperature for 0.5-1 hour to obtain ASA latex;

(5) and (4) drying the latex obtained in the step (4) to obtain the ASA high-glue powder.

Preferably, the reactive emulsifier in step (1) is one or a mixture of more of acrylamide isopropyl sodium sulfonate, sodium vinyl sulfonate, 2-propyl ether 3-hydroxypropane-1-sodium sulfonate, allyl ether hydroxypropane sodium sulfonate, allyl polyether sulfate, alkylphenol allyl propyl polyether sulfate and allyl alcohol ether-containing sulfate.

Preferably, the electrolyte in the step (1) is one or a mixture of potassium carbonate, sodium carbonate, potassium bicarbonate, sodium chloride, sodium sulfate and potassium sulfate.

Preferably, the initiator I in the step (1) is one or a mixture of potassium persulfate, ammonium persulfate and sodium persulfate.

Preferably, the acrylate monomer in the step (2) and the step (3) is one or a mixture of butyl acrylate, butyl methacrylate, isooctyl acrylate and ethyl acrylate; one or more of divinylbenzene, ethylene glycol dimethacrylate, triallyl isocyanurate and dicyclopentenyl acrylate as the crosslinking agent are mixed; the grafting agent is one or a mixture of allyl methacrylate and allyl acrylate.

Preferably, the initiator in the step (4) is cumene hydroperoxide; the chelating agent is one of sodium pyrophosphate or disodium ethylene diamine tetraacetate; the auxiliary reducing agent is one of fructose, glucose and sodium formaldehyde sulfoxylate; the reducing agent is ferrous sulfate.

Preferably, the drying in step (5) is spray drying or flocculating and precipitating drying.

Preferably, the spray drying is spray drying in a spray dryer under air or nitrogen conditions.

Preferably, the flocculating agent in the flocculation precipitation drying is one or a mixture of sulfuric acid, magnesium sulfate, calcium chloride, potassium chloride and sodium chloride.

According to the technical scheme, compared with the prior art, the invention discloses a preparation method of ASA high-glue powder, which has the following beneficial effects:

the adopted sulfonate or sulfate reactive emulsifier containing vinyl has stronger emulsifying capacity and stronger hydrophilicity of carboxylic acid or carboxylate with more carbon numbers. The molecular structure of the emulsifier contains polymerizable double bonds, and the emulsifier can be copolymerized with an acrylate monomer to finally form polyacrylate latex without free emulsifier molecules; in addition, the emulsifier is produced industrially in large scale, and is low in market price and wide in source.

Detailed Description

The technical solutions of the present invention will be described clearly and completely with reference to the following embodiments of the present invention, and it should be understood that the described embodiments are only a part of the embodiments of the present invention, and 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

(1) Putting 2 parts of acrylamide isopropyl sodium sulfonate, 0.5 part of sodium vinyl sulfonate, 0.5 part of sodium allyl ether hydroxypropane sulfonate, 0.3 part of electrolyte potassium carbonate, 0.5 part of sodium carbonate, 0.1 part of sodium chloride and 0.3 part of initiator potassium persulfate into a reaction kettle in parts by mass, adding 40 parts of deionized water, and starting a stirring device to stir until the mixture is completely dissolved;

(2) adding 5 parts of reaction monomer butyl acrylate, 0.2 part of crosslinking agent ethylene glycol dimethacrylate and 0.2 part of grafting agent allyl methacrylate into the reaction kettle in the step (1), removing air in the reaction kettle by using nitrogen, heating to 65 ℃, and reacting for 0.5 h;

(3) calculated by mass parts, dropwise adding 55 parts of reaction monomer butyl acrylate, 2 parts of crosslinking agent ethylene glycol dimethacrylate and 2 parts of grafting agent allyl methacrylate into the reaction kettle in the step (2), wherein the dropwise adding time is 3h, after the dropwise adding is finished, the temperature of the reaction kettle is set to be 85 ℃, and the heat preservation is carried out for 0.5h to obtain polyacrylate latex with the particle size of 270nm, and the polyacrylate latex is diluted by deionized water to have the solid content of 30%;

(4) taking 100 parts by mass of the polyacrylate latex diluted in the step (3), placing the polyacrylate latex into a grafting reaction kettle, adding 0.1 part of initiator cumene hydroperoxide, 0.2 part of chelating agent sodium pyrophosphate, 0.1 part of auxiliary reducing agent glucose and 0.002 part of reducing agent ferrous sulfate, removing air in the grafting reaction kettle by nitrogen, heating to 65 ℃, then dropwise adding 15 parts of styrene monomer, 5 parts of acrylonitrile monomer and 0.1 part of initiator cumene hydroperoxide, wherein the dropwise adding time is 2 hours, heating to 85 ℃ after the dropwise adding is finished, and keeping the temperature for 0.5 hour to obtain ASA latex;

(5) and (4) cooling the ASA latex obtained in the step (4) to room temperature, and then performing spray drying on the ASA latex by using a spray dryer under the condition of air or nitrogen to obtain the ASA high-rubber powder.

Example 2

(1) Putting 1 part of reactive emulsifier 2-propyl ether 3-hydroxy propane-1-sodium sulfonate, 1 part of vinyl sodium sulfonate, 0.8 part of electrolyte potassium carbonate and 0.3 part of initiator ammonium persulfate into a reaction kettle, adding 40 parts of deionized water, starting a stirring device, and stirring until the deionized water is completely dissolved;

(2) adding 2.5 parts of reaction monomers of butyl acrylate, 2.5 parts of isooctyl acrylate, 0.1 part of cross-linking agent of divinylbenzene, 0.2 part of triallyl isocyanurate and 0.2 part of grafting agent of allyl acrylate into the reaction kettle in the step (1), removing air in the reaction kettle by using nitrogen, heating to 55 ℃, and reacting for 1 hour;

(3) calculated by mass parts, 27.5 parts of reaction monomers of butyl acrylate, 27.5 parts of isooctyl acrylate, 0.5 part of cross-linking agent of divinylbenzene, 1.5 parts of triallyl isocyanurate and 2 parts of grafting agent of allyl acrylate are dripped into the reaction kettle in the step (2), the dripping time is 3 hours, the temperature of the reaction kettle is set to be 85 ℃ after the dripping is finished, the temperature is kept for 0.5 hour, polyacrylate latex with the particle size of 262nm is obtained, and the polyacrylate latex is diluted by deionized water to have the solid content of 30 percent;

(4) taking 100 parts by mass of the polyacrylate latex diluted in the step (3), placing the polyacrylate latex into a grafting reaction kettle, adding 0.1 part of initiator cumene hydroperoxide, 0.2 part of chelating agent disodium ethylene diamine tetraacetate, 0.1 part of auxiliary reducing agent sodium formaldehyde sulfoxylate and 0.002 part of reducing agent ferrous sulfate, removing air in the grafting reaction kettle by nitrogen, heating to 65 ℃, then dropwise adding 22.5 parts of styrene monomer, 7.5 parts of acrylonitrile monomer and 0.1 part of initiator cumene hydroperoxide, wherein the dropwise adding time is 2 hours, heating to 85 ℃ after the dropwise adding, and keeping the temperature for 0.5 hour to obtain ASA latex;

(5) and (4) cooling the ASA latex obtained in the step (4) to room temperature, and then performing spray drying on the ASA latex by using a spray dryer under the condition of air or nitrogen to obtain the ASA high-rubber powder.

Example 3

The difference from example 2 is that the electrolytic potassium carbonate content in step (1) was adjusted to 1.2 parts, the steps and the amounts were the same, and the particle size of the acrylic latex obtained in step (3) was 357 nm.

Comparative example 1

The difference from example 2 is that the emulsifier in step (1) is replaced by 2 parts of the conventional adsorptive emulsifier sodium dodecyl sulfate, the rest steps and the amount are the same, and the particle size of the acrylic latex obtained in step (3) is 179 nm.

Test examples

The ASA latices obtained in the above examples and comparative examples were tested for their average particle size and distribution using a dynamic light scattering laser particle sizer (Malvern, ZS-90). The ASA high-gel powders obtained in the above examples and comparative examples were tested for initial whiteness and whiteness after air aging at 200 ℃ for 1 hour using a whiteness tester, and the test results are summarized in the following table:

results of tests on the performance of ASA graft emulsion and the performance of high rubber powder in examples and comparative examples

The above test results show that the materials prepared in examples 1 to 3 of the technical scheme of the present invention have better properties than those of the comparative example, and the summary examples are different from the comparative example in that the present invention prepares polyacrylate latex using a sulfonate or sulfate type reactive emulsifier containing double bonds and prepares ASA latex using the same, and the ASA latex has low impurity content of ASA high rubber powder obtained due to the fact that no adsorptive emulsifier is added in the whole process of ASA latex preparation, has higher whiteness, and the whiteness after aging is better than that of comparative example 1.

The embodiments in the present description are described in a progressive manner, each embodiment focuses on differences from other embodiments, and the same and similar parts among the embodiments are referred to each other. The device disclosed by the embodiment corresponds to the method disclosed by the embodiment, so that the description is simple, and the relevant points can be referred to the method part for description.

The previous description of the disclosed embodiments is provided to enable any person skilled in the art to make or use the present invention. Various modifications to these embodiments will be readily apparent to those skilled in the art, and the generic principles defined herein may be applied to other embodiments without departing from the spirit or scope of the invention. Thus, the present invention is not intended to be limited to the embodiments shown herein but is to be accorded the widest scope consistent with the principles and novel features disclosed herein.