摘要
利用原子力显微镜(AFM)、橡胶加工分析仪(RPA)、拉伸试验机以及动态力学分析仪(DMA)等技术研究了液体异戊二烯-丁二烯嵌段共聚物橡胶(LIR-390)对天然橡胶(NR)和顺丁橡胶(BR)微观形貌、加工性能、拉伸性能及抗开裂等行为的影响。AFM结果显示:液体嵌段共聚物橡胶LIR-390在NR和BR中自组装形成了胶束:在NR中,LIR-390形成了以丁二烯(PB)嵌段为核、异戊二烯(PI)嵌段为壳的胶束;在BR中,LIR-390却形成了反相胶束(PI嵌段为核、PB嵌段为壳)。另外,LIR-390的加入改善了NR、BR的加工性能,但也降低了拉伸性能、弹性模量,并且不利于降低硫化胶的滚动阻力。橡胶裂纹扩展测试结果显示:LIR-390胶束在NR基体中作为缺陷,破坏了NR硫化胶的抗开裂性能,裂纹生长速率加快,开裂后的表面形貌也变得更加平滑。
The effects of LIR- 390 on the morphologies, processing characteristics, tensile properties and fatigue crack growth resistance of NR and BR were investigated by atomic force microscopy （AFM）, rubber processing analysis （RPA）, tensile tester and dynamic mechanical analysis （DMA）. AFM results show that LIR- 390 forms micelles in NR and BR： in NR, LIR-390 forms micelles with PB cores and PI coronas; while in BR, LIR-390 forms inverted micelles with PI cores and PB coronas. The processing characteristics of NR and BR are improved, while the tensile properties and dynamic modulus of NR and BR vulcanizates slightly decrease, respectively. Meanwhile, the loading of a small amount of LIR -390 may increase the rolling resistance of NR and BR, respectively. The fatigue crack propagation measurement reveals the higher crack growth rate for NR/LIR vulcanizate, and the smoother crack surface morphology as observed in scanning electron microscopy （SEM）.
基金
化学工程联合国家重点实验开放课题(SKL-ChE-12D01)
宁波市"3315"计划(A类)(2012S0001)
浙江省重点科技创新团队计划(2011R50001)
宁波市科技局/农业与社会发展攻关项目(2011A31002)
