硫化体系对氢化丁腈橡胶高温拉伸性能的影响

Effects of curing systems on high temperature tensile properties of hydrogenated nitrile rubber vulcanizates

研究了硫黄、过氧化物和给硫体3种硫化体系对氢化丁腈橡胶(HNBR)高温拉伸性能的影响,采用热重分析考察了HNBR硫化胶的耐热性能,并通过核磁共振波谱测定了不同温度下HNBR硫化胶的交联密度。结果表明,随着温度从30℃升至180℃,采用不同硫化体系硫化HNBR的拉伸强度和扯断伸长率均明显下降,交联密度减小。当测试温度为90℃时,过氧化物硫化HNBR的拉伸强度为13.2 MPa,分别比硫黄和给硫体硫化者高出3.9 MPa和3.2 MPa;当测试温度为180℃时,过氧化物硫化HNBR的扯断伸长率为150%,是硫黄硫化者的2倍。过氧化物硫化HNBR的起始分解温度分别比硫黄和给硫体硫化者高12.0℃和5.0℃。采用过氧化物硫化HNBR的高温拉伸性能和耐热性能要优于硫黄和给硫体硫化者。

The effects of different curing agents, such as sulfur, peroxide and sulfur donor, on the high temperature tensile properties of hydrogenated nitrile rubber （HNBR） were studied. The heat re- sistance properties of HNBR vulcanizates were inves- tigated by thermogravimetric analysis, and the crosslinking density of HNBR vulcanizates at differ- ent temperatures was measured by nuclear magnetic resonance spectroscopy. The results showed that the all tensile strength, elongation at break and crosslinking density of HNBR cured with different curing systems decreased significantly with increas- ing test temperature from 30 ℃ to 180 ℃. At 90 ℃ , the tensile strength of HNBR cured withperoxide was 13.2 MPa, 3.9 MPa and 3.2 MPa more than that of HNBR cured with sulfur and sulfur donor, respectively. The elongation at break of per- oxide cured HNBR was 150% at 180 ℃, doubled that of sulfur cured HNBR. The initial decomposi- tion temperature of HNBR cured with peroxide was 12.0 ℃ and 5.0 ℃ higher than that of HNBR cured with sulfur and sulfur donor, respectively. The peroxide cured HNBR showed better high tem- perature tensile properties and heat resistance than HNBR cured with sulfur and sulfur donor.