含氟丙烯酸酯三元共聚物乳液的研究

THE STUDY OF THE ACRYLATE COPOLYMER EMULSION CONTAINING FLUORINE

以丙烯酸全氟烷基酯 (ZonylTM)、甲基丙烯酸甲酯 (MMA)、丙烯酸丁酯 (BA)为原料 ,在阴离子乳化体系中制备了含氟丙烯酸三元共聚物乳液 .研究了聚合反应动力学、转化率的各种影响因素 ,得出了聚合速率方程 ,并得出反应的表观活化能 (Ea)为 5 0 75 8kJ mol.考察了乳液的稀释稳定性、贮存稳定性、离心稳定性、耐热、耐寒稳定性 ,及乳胶膜的吸水性和耐溶剂性 .并用Wilhelmy方法测定了乳胶膜与水的接触角 。

Fluoropolymer films have so low surface energy that they have good special surface properties, such as water-resistant, oil-resistant and self-cleaning properties. Nowdays, surface properties of polyacrylates can be modified by introducing fluorine-containing groups to polymer chains. The acrylate copolymer emulsion containing fluorine was prepared, with fluoromoner ( Zonyl TM), butyl acrylate ( BA), methyl methylacrylate (MMA) as monomers, sodium dodocyl sulfonate ( SDS) as emulsifier. The solid content of copolymer emulsion was about 25wt%. The kinetics of emulsion copolymerization was studied by the weight method. The effects of the concentration of emulsifier, initiator, monomer and polymerization temperature on polymerization rate (R-p) were investigated in detail. The results showed that R-p proportional to [SDS](0.28), R-p proportional to [I](0.98). The apparent activation energy was 50.756 kJ.mol(-1). The copolymer emulsions had no change after stored at room temperature for 72 h, at 60degreesC for 48 h and at -5degreesC for 24 h respectively. The centrifugal stability of emulsions was characterized at 12000 r/min for 120 min. The sedimentation ratios showed that the centrifugal stability of emulsions increased with increasing the amount of emulsifier, while decreased with increasing the amounts of initiator and fluoromonomer respectively. The latex films could be dissolved in THF and toluene, while could be swelled in methanol and ethanol. The water absorption of latex films decreased with increasing the amount of fluoromonomer. The surface property of films was determined by Wilhelmy method. The contact angles for latex films to water increased apparently by introducing fluorine-containing groups, above 100degrees. This result showed the water-resistant property of copolymer latex films containing fluorine was improved.