丙烯酸型亲水涂料乳胶粒表面羧基分布的研究  

Study on Carboxyl Group Distribution on the Surface of the Latex Particles of Acrylate Based Hydrophilic Coatings

作　　者：王连盛[1] 徐楠[1] 刘亚康[1] 

机构地区：[1]北京化工大学材料学院,北京100029

出　　处：《涂料工业》2006年第7期41-45,共5页Paint & Coatings Industry

摘　　要：研究了以苯乙烯为核,丙烯酸酯类为壳的核壳乳液,采用丙烯酸为功能性单体,成膜后羧基为极性基团分布在涂膜表面达到亲水目的。讨论了功能单体丙烯酸(AA)在乳胶粒表面的分布情况及其加量对涂膜亲水性的影响,通过电导滴定发现当AA的加入量为3%时,水相中游离的丙烯酸含量为5.57%,聚合物表面的羧基含量为36.11%,涂膜的亲水性达到最佳,水接触角为51.1°。本文还讨论了核壳法和核壳翻转法对乳胶粒表面羧基分布及涂膜亲水性能的影响,两者的电导滴定曲线形状一致,由两个当量点可以计算出水相中游离的丙烯酸含量为1.47%,而乳胶粒表面羧基分布的含量为43.59%,可见,用核壳翻转法合成的乳液,乳胶粒表面羧基分布含量比普通聚合方法合成的乳胶粒表面羧基分布含量高,涂膜亲水性进一步提高,水接触角降低为44.5°。The title hydrophilic coatings has been prepared by use of core - shell structure emulsion （ styrene as core, acrylate as shell and acrylic acid as functional monomer）. The carboxyl groups are distributed on the film surface to improve the hydrophile. The distribution of acrylic acid （AA） on particle surface and influence of its amount on hydrophile of film are discussed. It is found that when amount of AA is 3% , the free AA in water phase is 5.57% and carboxyl group on particle surface is 36. 11%. hydrophile of film shows the best and water contact angle is only 51.10°. The influence of core - shell structure and reverse core -shell structure on carboxyl distribation and hydrophile are also discussed, with a same conductometric titration curves. The calculation shows that free AA is water phase is 1.47% and 43.59% of carboxyl groups on the surface. It is concluded that the emulsion prepared by use of reverse core - shell structure process can imorove the film hvdrophile and water contact angle is only 44. 5°.

关 键 词：丙烯酸 羧基分布 水接触角 亲水性 

分 类 号：TQ630.72[化学工程—精细化工]