作　　者： ; ; ;

机构地区： 华南理工大学材料科学与工程学院

出　　处： 《弹性体》 2004年第3期18-22,共5页

摘　　要： 测试了三元乙丙橡胶(EPDM)混炼胶的结合橡胶含量,硫化胶的表观交联密度,采用FT IR表征了不饱和羟基脂肪酸在EPDM硫化胶中的反应,DMTA研究了硫化胶的动态力学性能,SEM观察了EPDM硫化胶中炭黑的表面形貌。结果表明:EPDM混炼胶的结合橡胶含量随着不饱和羟基脂肪酸的加入出现一个峰值,表观交联密度略有下降;不饱和羟基脂肪酸参与了EPDM硫化胶的反应,提高了常温范围内EPDM硫化胶的损耗因子;适量的不饱和羟基脂肪酸可以改善炭黑在EPDM橡胶中的分散。最后提出了一个不饱和羟基脂肪酸补强橡胶的模型,认为不饱和羟基脂肪酸在EPDM硫化胶中起到柔性桥键的作用,阻碍了炭黑聚集体的形成,是硫化胶屈挠疲劳性能显著改善的主要原因。 In this paper the bound rubber of EPDM compounds and apparent crosslinking density of EPDM vulcanizates were measured,the reactions of unsaturated hydroxyl fatty acid in EPDM vulcanizates filled with carbon black were proved by means of FT-IR,the dynamical-mechanical properties of EPDM vulcanizates and the dispersion of carbon black in EPDM vulcanizates were investigated by DMTA and SEM,respectively.The results showed that the unsaturated hydroxyl fatty acid reacted with both carbon black and EPDM macromolecules,the bound rubber of EPDM compounds passed through a maximum as the concentration of unsaturated hydroxyl fatty acid increased,whereas the apparent crosslinking density decreased slowly with the increasing of unsaturated hydroxyl fatty acid,the loss factor of EPDM vulcanizates increased at the room temperature regions as the concentration of unsaturated hydroxyl fatty acid increased,too.The dispersion of carbon black in EPDM vulcanizates was enhanced remarkably with the addition of unsaturated hydroxyl fatty acid.And at last,a model of modified in-situ EPDM vulcanizates filled with carbon black by unsaturated hydroxyl fatty acid was designed,the action of unsaturated hydroxyl fatty acid was similar to 'flexible bridge bonds',which combined tightly carbon black and EPDM macromolecules,hindered the formation of carbon black aggregates,and with the results the better flex cracking and good vibration damping properties at the room temperature regions of EPDM vulcanizates were achieved.

关 键 词： 不饱和羟基脂肪酸 原位改性 炭黑 补强 结构 形态 三元乙丙橡胶 混炼胶

领　　域： [化学工程]