摘要
研究了用包括过渡金属离子在内的二价(或三价)金属离子或胺中和的磺化乙丙橡胶离聚体,在Brabender塑性仪上的熔融加工性能和力学性能。结果表明,用胺中和的离聚体比用金属离子中和的离聚体容易加工。用乙胺中和的离聚体随离子增塑剂用量的增加,其拉伸强度及扯断伸长率均先增大而后减小,永久变形时逐步增大。当磺化度小于0.14mmol/g时,用异丙胺中和的离聚体拉伸强度低,而扯断伸长率及永久变形大;当磺化度大于0.25mmol/g时,则呈现热塑性弹性体行为。用不同胺类中和的离聚体的拉伸强度依下列次序递减:异丙胺,乙胺,二乙胺;用金属离子中和的离聚体的拉伸强度为(>表示优于):Pb^(2+)>Cu^(2+),Ba^(2+),Co^(2+)>Ni^(2+),Ce^(3+)>Al^(3+)。
The melt flow behavior and mechanical propedrties of the sulfonated EPDM ionomers neutralized with different divalent or bivalent cations , including transition metallic ions , as well as amines were studied .The ionomers were prepared through sulfonation of EPDM in petroleum ether solution using sulfuric acid and acetic anhydride as sulfonating agent , followed by neutralization with alcoholic solution of metallic salts or amines . The melt viscosity was represented by mixing torque value measured by Brabender Plasticorder with a shear rate of 30 r/min .Mechanical properties were measured on a XL-100 A Tensile Tester .The results showed that the amine neutralized ionomer can be processed much easier than metallic ion neutralized ionomer due to the higher ionic potential of the metallic ion . Torque value decreased with increasing neutralization degree . This can be explained by a change of ionic crosslinkage to ionic association .At neutralization degree of 1 molar ratio , torque value of ionomers neutralized with different metallic ions decreased in the following order :Cu2+>Ce3+>Ni2+>Pb2+In the case of ethylamine neutralized ionomer , with increasing amount of ionic plasticizer zinc stearate added , tensile strength and ultimate elongation increased at first and then decreased .while permanent set increased gradually .This is because ionic plasticizer can make the ionic domains of the ionomer distribute more uniformly , while excess ionic plasticizer merely acts as filler . More zinc stearate is needed in the case of lead ion neutralizedionomer than in the case of amine neutralized ionomer and the effect on increasing tensile strength is more obvious in the former case . The effect of lead stearate on increasing tensile strength of the ionomer is less effectivethan that of zinc stearate . The amine neutralized ionomer with sulfonation content below 0.14 mmol/g EPDM showed low tensile strength and large ultimate elongation and permanent set , similar to the unvulcanized EPDM rubber . The ionomer with sulfonate content above 0.25 mmol/g EPDM exhibited thermoplastic rubber behavior . The ionomer with neutralization degree at 1 molar ratio showed better mechanical properties than those with smaller or excess molar ratio , since excess amine inserts between ionic pairs and weakens the interaction . The tensile strength of the ionomers neutralized with different amines decreased in the following order : isopropyl amine > ethylamine >diethylamineThe sulfonated EPDM ionomer neutralized with differ ent amines can be processed without using ionic plastieizer . Although its tensile strength is lower than that of amine neutralized sulfonated IIR ionomer , its ultimate elongation is still high and permanent set very low .Tensile strength of the sulfonated EPDM ionomers neutralized with various metallic ions decreased in the following order :Pb2+>Cu2+ ,Ba2+ ,Co2+>Ni2+ ,Ce3+>Al3+
出处
《合成橡胶工业》
CAS
CSCD
北大核心
1992年第1期44-47,共4页
China Synthetic Rubber Industry
基金
国家自然科学基金
关键词
弹性体
离聚体
磺化
乙丙橡胶
ethylene-propylene-diene rubber
sulfonation
ionomer
thermoplastic elastomer
mechanical property
melt flow property
