摘要
以苯乙烯（St）、丙烯酸异辛酯（EA）和丙烯酸丁酯（BA）为主要单体，丙烯酸（AA）为功能单体，十二烷基苯磺酸钠（SDS）和壬基酚聚氧乙烯醚（OP-10）为复合乳化剂，γ-甲基丙烯酰氧基丙基三甲氧基硅烷（KH570）、乙烯基三甲氧基硅烷（A-171）和八甲基环四氧硅烷（D4）为有机硅改性剂，通过乳液聚合合成了不同有机硅改性苯丙乳液。研究了复合乳化剂的用量及配比，软硬单体质量比，以及复合有机硅改性剂的配比与用量对苯丙乳液性能的影响，确定了合成有机硅改性苯丙乳液的较佳用量：有机硅的质量分数为6％，软单体（EA、BA）和硬单体（St）的质量比为1：2，OP-10与SDS的质量比为3：2，且复合乳化剂的用量为3％。通过红外光谱和热重分析对苯丙乳液，KH570、A-171或D4单一改性以及复合改性苯丙乳液进行了表征，测试了各种乳液及其涂膜的性能。结果表明，有机硅改性后苯丙乳液的综合性能明显提高，复合有机硅改性苯丙乳液的性能最好。当复合有机硅中KH570、A-171和D4的质量比为1：2：1时，合成的复合有机硅改性苯丙乳液的固含量为41．33％，粒径80．09nm，黏度127mPa·s，其漆膜硬度为2H，吸水率9．34％，失重温度区间在450～520℃，高于苯丙乳液的350～420℃以及由KH．570、A．171或D4单一改性苯丙乳液的390～430℃。
Different organic silicon modified styrene acrylic emulsions were synthesized by emulsion polymerization with styrene （St）, 2-ethylhexyl acrylate （EA）, and n-butyl acrylate （BA） as main monomers, acrylic acid （AA） as functional monomer, sodium dodecylbenzene- sulfonate （SDS） and polyoxyethylene nonylphenol ether （OP-10） as composite emulsifier, and γ-methacryloxypropyl-trimethoxysilane （KH-570）, vinyltrimethoxysilane （A-171） or/and octamethylcyclotetrasiloxane （D4） as organic silicon modifiers. The effects of the dosage and mixing ratio of composite emulsifier, the mass ratio of soft to hard monomers as well as the mixing ratio and dosage of composite organic silicon modifier on the properties of styrene-acrylic emulsion were examined. The optimal conditions for synthesis of organic silicon-modified styrene-acrylic emulsion were determined as follows： mass fraction of organic silicon 6%, mass ratio of soft monomers （EA and BA） to hard monomer （St） 1：2, mass ratio of OP-10 to SDS 3：2, and dosage of composite emulsifier 3%. The styrene-acrylic emulsion with and without modification by single and combination of KH-570, A-171, and D4 were characterized by infrared spectroscopy and thermogravimetry. The properties of various emulsions and their coatings were studied. The results showed that the comprehensive performance of the styrene-acrylic emulsion is remarkably improved by modifying by organic silicon. The styrene- acrylic emulsion modified by composite organic silicon has the best performance. The styrene-acrylic emulsion modified by KH-570, A-171, and D4 at a mass ratio of 1：2：1 has a solid content of 41.33%, particle size 80.09 nm, and viscosity 127 mPa.s. The coating obtained therefrom has a hardness of 2H, water absorption 9.34%, and weight loss temperature in range of 450-520 ℃, which is higher than that of the unmodified styrene-acrylic emulsion （350-420 ℃） and that of the styrene-acrylic emulsion modified by single KH-570, A-171, or D4 （390-430 ℃）.
出处
《电镀与涂饰》
CAS
CSCD
北大核心
2014年第14期598-603,共6页
Electroplating & Finishing
关键词
苯丙乳液
硅烷
改性
乳液聚合
styrene-acrylic emulsion
saline
modification
emulsion polymerization
