炭黑对丁苯橡胶耐热氧和紫外老化性能的影响  

Effect of carbon black on thermal-oxidative and ultraviolet aging resistance of styrene-butadiene rubber vulcanizates

作　　者：刘宏敏[1] 杨其[1] 冯彦龙[1] 刘小林[1] 

机构地区：[1]四川大学高分子科学与工程学院高分子材料工程国家重点实验室,四川成都610065

出　　处：《合成橡胶工业》2009年第1期53-57,共5页China Synthetic Rubber Industry

基　　金：国家自然科学基金重点资助项目(50533080);贵州省重点技术创新项目(061008)

摘　　要：研究了填充不同量炭黑对丁苯橡胶耐热氧和紫外老化性能的影响,测试了各试样的交联密度及物理机械性能,并用扫描电镜观察了其表面形貌。结果表明,丁苯橡胶在热氧老化开始时内部发生了以交联为主的反应,表面氧化缓慢;而在紫外老化开始时表面的变化较大,在老化过程中交联密度出现峰值;热氧和紫外老化120h后,橡胶的硬度增加,表面变得致密,使热氧和紫外线侵入至橡胶内部变得困难,邵尔A硬度等物理机械性能的变化趋势减缓;炭黑填充量大于20份(质量)时SBR的耐紫外老化性能得到改善,老化360h后物理机械性能保持率仍然较高,这是因为炭黑对紫外线有很好的屏蔽作用,而炭黑对SBR耐热氧老化性能的影响却相反。The thermal-oxidative and ultraviolet （UV） aging resistance of styrene-butadiene rubber （SBR） vuleanizates filled with different amount of carbon black were investigated, its erosslinking density and mechanical properties were measured, and its surface morphology was observed with scanning electron microscope. The results showed that the crosslinking occurred mainly in the inner SBR vulcanizate in the initial period of thermal-oxidative aging, but its surface oxidation was slow. However, the ozonition reaction occurred on the surface of SBR vulcanizate at the beginning of UV aging treatment, and the maximum value of erosslinking density appeared during the aging process. After 120 h of thermal-oxidative and UV aging, the hardness of the vulcanizate increased, its surface got densified, and it was difficult for oxygen and UV to go into the inner vulcanizate, so the variation for the mechanical properties such as Shore A hardness slowed down. As the level of carbon black was more than 20 phr, the UV aging resistance of the vuleanizate was improved, and after 360 h of aging, the percentage retention of mechanical properties was still higher because of the shielding effect of carbon black from UV. But the influence of carbon black on the thermal-oxidative aging resistance was just opposite to it.

关 键 词：丁苯橡胶 炭黑 热氧老化 紫外老化 交联密度 物理机械性能 

分 类 号：TQ333.1[化学工程—橡胶工业]