乳液pH值对乳胶粉及其涂料分散涂膜的影响  

Influences of pH Value of Spray Emulsion on Dispersibility and Film Properties of Polymer Powders and Their Paints

作　　者：司徒粤[1] 周利庄[1] 蓝仁华[1] 夏正斌[1] 陈焕钦[1] 

机构地区：[1]华南理工大学化学与化工学院,广东广州510640

出　　处：《建筑材料学报》2011年第4期486-491,共6页Journal of Building Materials

基　　金：科技型中小企业技术创新基金初创期小企业创新项目(08C26214402212)

摘　　要：采用喷雾干燥法制备可再分散苯丙乳胶粉,探讨喷雾乳液pH值对苯丙乳胶粉及其再分散乳液性能的影响,并分析其作用机理;以不同pH值喷雾乳液制备的乳胶粉为成膜物质配制干粉涂料,研究各涂料样品的施工稳定性,并观察漆膜断面微观形貌.结果表明:随着喷雾乳液pH值增大,乳胶粉的再分散性提高、堆积密度增大,再分散乳液粒径变小,施工稳定性增强,漆膜中成膜物质对颜填料包裹更充分,但乳胶粉分散再成膜的吸水率有所升高;再分散乳液ζ电位随喷雾乳液pH值增大而先升高后降低,证实乳胶粉的再分散稳定机理为形成亲水"发状结构".综合各项性能,喷雾乳液最佳pH值为8.5.Redispersible styrene-acrylic polymer powders were prepared by spray drying.The influence of pH value of spray emulsion on the properties of redispersible polymer powders and their redispersed emulsions was discussed.Polymer powders obtained with different pH value for spray emulsion were adopted to prepare dry powder paints.The stability of the redispersed dry powder paints and the microtopography of paint films were investigated.The results show that the redispersibility and bulk density of redispersible polymer powders,the stability of corresponding dry powder paint and the water absorption of polymer film increase with the increase of pH value of spray emulsion,meanwhile the particle size of redispersed emulsion decreases.The SEM photography has been shown that with higher pH value for spray emulsion,pigments and fillers were bonded more tightly by styrene-acrylate polymer and an uniform paint film was obtained.ζ potential of redispersed emulsion elevated and decreased afterward with the increase of pH value,demonstrated that the hydrophilic hairy structure was obtained at the surface of particles.Taking the comprehensive properties of polymer powder into consideration,the optimal value of pH for spray emulsion was 8.5.

关 键 词：可再分散苯丙乳胶粉 干粉涂料 喷雾乳液pH值 

分 类 号：TQ331.4[化学工程—橡胶工业]