【摘要】 采用无喷霜硫黄硫化体系,考察了硫黄用量对三元乙丙橡胶(EPDM)/白炭黑(WCB)混炼胶硫化特性及硫化胶物理机械性能、耐热老化性能、动态力学性能和压缩永久变形的影响。结果表明,在硫黄用量为0.5~1.5份的条件下,随着硫黄用量的增加,EPDM/WCB混炼胶的硫化速率减慢,硫化胶的拉伸强度先升高后下降,当硫黄用量为1.00份时达到最大值(22.4 MPa),同时扯断伸长率和永久变形逐渐下降,邵尔A硬度升高;热空气老化后,硫化胶的拉伸强度、撕裂强度和硬度均提高,但扯断伸长率下降幅度较大;随着硫黄用量的增加,硫化胶的玻璃化转变温度向高温方向移动,损耗因子峰值先升高后下降,储能模量增大,压缩永久变形略有减小。更多还原

【Abstract】 Based on a non-blooming sulfur cure system,effects of sulfur amount on curing characteristics of ethylene-propylene-diene monomer( EPDM) /white carbon black( WCB) compounds,and mechanical properties,heat aging resistance,dynamic mechanical properties and compression set of EPDM /WCB vulcanizates were investigated. The results showed that with increasing sulfur amount from0. 5 phr to 1. 5 phr,the curing rate of EPDM / WCB compounds decreased,tensile strength of vulcanizates increased firstly and then decreased, and reached the maximum( 22. 4 MPa) when sulfur was1. 00 phr,meanwhile,elongation at break and permanent set decreased,and Shore A hardness increased. After hot air aging,the tensile strength,tear strength and Shore A hardness of vulcanizates increased,but elongation at break decreased significantly. With increasing sulfur amount, the glass transition tempetature of the vulcanizates shifted to higher temperature,loss factor peak value increased firstly and then decreased, storage modulus increased and compression set decreased slightly.更多还原