辐射引发乳液共聚制备的羧基交联型丙烯酸酯橡胶的性能研究及与常规方法制备的同类橡胶的比较(英文)

A comparison of properties between carboxylated acrylic rubbers prepared by γ-ray irradiation and chemical method

由60Coγ射线引发或化学引发剂(K2S2O8)引发的乳液共聚法,制备了以丙烯酸或衣康酸为交联单体的羧基交联型丙烯酸酯橡胶(ACM)。用红外光谱(FT-IR)表征了产物分子结构,用非水滴定方法分析了产物的酸值,用凝胶渗透色谱(GPC)测定了聚合物分子量和分子量多分散系数。用硫化仪分析、凝胶含量测定、机械性能测试和动态力学性能分析研究了交联单体的种类和用量对橡胶的硫化和性能的影响。结果表明,在相同的配方条件下,同化学法制备的聚合物相比,辐射法制备的聚合物的酸值较低,分子量较高,分子量多分散系数较小。以衣康酸为交联单体的ACM的硫化特性和机械性能好于以丙烯酸为交联单体的ACM。对于以衣康酸为交联单体的ACM,辐射法制备的橡胶比化学法制备的橡胶拥有更好的硫化特性、更高的凝胶含量和更优异的机械性能。

Acrylic rubbers （ACM） carboxylated by acrylic acid or itaconic acid were prepared by ^60Co γ-ray or chemical-initiator （K2S208） induced emulsion copolymerization. The polymers were characterized by Fourier transform infrared spectroscopy （FF-IR）. Acid value, molecular weight and polydispersity index （PDI） of the polymers were determined by non-aqueous titration method and gel permeation chromatography （GPC）, respectively. Vulcanization and mechanical properties of the filled ACM were studied by rheometric measurement, gel fraction analysis, mechanical property tests and dynamic mechanical thermal analysis （DMTA）. The results show that the ACMs prepared by γ-ray irradiation have lower acid value, higher molecular weight and narrower PDI than chemically prepared ACMs of the same composition. The itaconic acid carboxylated ACM has better cure characteristics and mechanical properties than the acrylic acid carboxylated ACM. The itaconic acid carboxylated ACM prepared by γ-ray irradiation has higher gel fraction and better cure characteristics as well as mechanical properties than that prepared by chemical method.