含不同金属离子的EPDM磺酸盐离聚物的研究

合成了含不同金属离子Na~+、Mg~(2+)、Zn~(2+)和Al~(3+)的四种乙丙三元共聚物(EPDM)磺酸盐离聚物, 红外光谱和氧瓶燃烧法测定了磺酸基的存在和含量。动态力学结果表明, 离聚物中碳酸盐基团可能以多重离子对形式聚集; 热重法指出, EPDM磺酸盐的热稳定性为钠盐>锌盐>镁盐>铝盐。考察了它们在二甲苯-正己醇混合溶剂中, 比浓粘度随浓度、温度变化的规律, 初步分析了各种金属盐的差异及其原因。

STUDY ON SULFONATED EPDM IONOMERS CONTAINING VARIOUS IONS

Sulfonated EPDM ionomers containing Na~+,Mg~(2+), Zn~(2+) and Al~(3+) have been synthesized and identified with IR spectra. Dynamic mechanical analyses showed that the ionic groups in ionomers have been aggregated to mutiplets instead of clusters. Ther-mogravimetry showed that the thermal stability of the ionomers is in an order as Na>Zn>Mg>Al. Viscometric behaviors of ionomers in xylene-5% hexanol mixed solvent are quitedifferent from that of EPDM owing to the interaction between ionic groups. The strengthof interaction of metallic ions with _-SO_3~- is in the order Na>Mg>Zn. This fact wasinterpreted by considering the different hexanol-solvation ability of different metallicions and the stability of the solvation layer around them.