炭黑用量对过氧化物硫化三元乙丙橡胶性能的影响

Effects of carbon black amount on properties of peroxide cured ethylene-propylene-diene rubber

以双叔丁基过氧化异丙基苯为硫化剂,通过无转子硫化仪、毛细管流变仪及橡胶加工分析仪考察了炭黑用量对乙烯含量不同的2种三元乙丙橡胶(EPDM)混炼胶硫化特性、流变行为、动态黏弹性能及硫化胶拉伸性能的影响。结果表明,随着炭黑用量的增加,2种EPDM混炼胶的焦烧时间(ts1)均缩短,正硫化时间均变化不大,门尼黏度均逐渐增大,混炼胶黏-切依赖性增大;在相同炭黑用量下,乙烯含量高的混炼胶的ts1较短,硫化程度和硫化速率提高,2种EPDM混炼胶均表现出剪切变稀行为,乙烯含量高的EPDM混炼胶的剪切弹性模量明显高于乙烯含量低的EPDM混炼胶;随着炭黑用量的增加,2种EPDM硫化胶的拉伸强度和100%定伸应力均不断提高,且高乙烯含量有助于提高EPDM硫化胶的拉伸性能。

Effects of carbon black amount on the curing characteristics,rheological behavior and dynamic mechanical properties of two kinds of ethylene-propylene-diene rubber（ EPDM） compounds with different ethylene contents and the tensile properties of EPDM vulcanizates were investigated usingα,α-bis-（ tert-butyl peroxy）-1,3-diisopropyl benzene as vulcanizator by moving die rheometer,capillary rheometer and rubber processing analyzer. The results showed that with the increase of carbon black,the scorch time of both EPDM compounds shortened,optimum cure time changed little,Mooney viscosity increased,and the shearing dependence of viscosity were enhanced. When the amount of carbon black was the same,the scorch time of EPDM compound with higher ethylene content was shorter,the degree and the rate of vulcanization increased,and both EPDM compounds exhibited obvious shear-thinning behavior with increasing shear rate. And shear modulus of EPDM compound with higher ethylene content was larger than that of the EPDM compound with lower ethylene content. With increasing carbon black, the tensile strength and modulus at 100% of EPDM vulcanizates increased,and with increasing ethylene content, the tensile properties of EPDM vulcanizates were improved.