沉淀聚合法制备粉末涂料用聚丙烯酸酯树脂

Preparation of Acrylic Resin for Powder Coatings by Precipitation Polymerization

以乙醇和去离子水为反应介质，通过沉淀聚合成功地合成了甲基丙烯酸缩水甘油酯-甲基丙烯酸甲酯-丙烯酸丁酯（GMA—MMA—BA）三元共聚丙烯酸酯树脂。用数码照片记录了随着最终聚合物液体温度的降低，合成的三元共聚物与介质自动分离的过程。利用扫描电镜研究了聚合物粒子的形貌及分布状况；利用红外光谱与核磁共振氢谱表征了合成树脂的结构；用凝胶渗透色谱仪测定了树脂的相对分子质量及其分布；用差示扫描量热仪测试了合成树脂的玻璃化转变温度；用热重分析仪测试了合成树脂的热稳定性。结果表明：共聚单体的转化率很高，可以通过调整MMA／BA的比值来调控合成树脂的玻璃化转变温度在55—75℃之间。

A glycidyl methacrylate-methyl methacrylate-n-butyl acrylate （GMA-MMA- BA） terpolymer was successfully synthesized via precipitation polymerization at the presence of ethanol and deionized water as media. The obtained terpolymer was separated from the said media as its temperature decreased, which was investigated by digital photos. Diameter distri- butions and morphology of the terpolymer particles were investigated by the scanning electron microscopy （SEM）. The structure of the terpolymer was characterized by FT- IR and 1H-NMR. Number-average molecular weight and polydispersity of the resulted resins were de- termined by gel permeation chromatography. The experimental results showed that the conversion of the comonomers was much high. The glass transition temperature of the terpolymer was from 55℃ to 75℃ adjusted effectively by changing the MMA/BA mass ratio. The synthesized terpolymer resin was suitable for powder coatings application.