高相对分子质量丙烯酸酯共聚物的制备及表征

以丙烯酸丁酯、丙烯酸乙酯和丙烯腈为主要单体,甲基丙烯酸羟乙酯和甲基丙烯酸羟丙酯为功能单体,采用悬浮聚合法制备高相对分子质量和高转化率的丙烯酸酯共聚物.考察引发剂种类和用量、聚合反应温度、分散剂类型和质量浓度、介质pH值等因素对聚合反应转化率和聚合物重均分子质量的影响,并用凝胶渗透色谱(GPC)、傅里叶变换红外光谱(FT-IR)和热重分析仪(TGA)对产物进行表征.结果表明:选择质量分数为0.66%的偶氮二异丁腈作为引发剂,质量分数为1.5%的自制无机-有机高分子(PVA混合物)作为分散剂,pH 值为7.5,65 ℃下聚合反应6 h,制得的共聚物重均分子质量可达6.86×10⁶,涂层抗渗水水柱高度超过2 000 mm,热分解温度为320 ℃,单体转化率为98.11%,聚合反应稳定,产品性状好.

Synthesis and Characterization of High Molecular Weight Acrylate Copolymer

The acrylate copolymers of high molecular weight and high conversion rate was synthesized with butyl acrylate, ethyl acrylate and acrylonitrile as main monomers, hydroxyethyl methyacrylate and hydroxypropyl methyacrylate as functional monomers by suspension polymerization. The effects of the type and concentration of initiators, polymerization temperature, the kind and concentration of dispersing agents, and pH value on the final molecular weight of the copolymer and conversion rate of monomers were investigated. The final products were characterized by GPC, FT-IR and TGA. The results showed that the weight-average molecular weight of copolymer could reach to 6.86×10⁶, the final conversion rate was 98.11%, the thermal decomposition temperature was above 320 ℃ and water colunm height was above 2 000 mm at following conditions, the amounts of initiator AIBN and homemade inorganic-organic macromolecular dispersing agent(PVA mixture)were 0.66% and 1.5% respectively, and the temperature and time of the suspension polymerization were 65 ℃and 6 h under pH=7.5 of reaction media.