干摩擦条件下氧化锌对丁腈橡胶摩擦磨损行为的影响

Effect of Zinc Oxide on Friction and Wear Behavior of NBR Under Dry Sliding

运用环-块摩擦磨损试验机研究了不同类型氧化锌对丁腈橡胶干摩擦磨损性能的影响。将不同类型氧化锌加入丁腈橡胶,对试样进行常规制备,磨损后橡胶表面分子结构利用红外光谱仪进行分析。结果表明,与添加普通氧化锌、纳米氧化锌和改性普通氧化锌的胶料相比,添加改性纳米氧化锌胶料表现出了优异的耐摩擦磨损性能。其磨损量为0.021g,仅为添加普通氧化锌胶料磨损量的1/4;摩擦系数为0.4,是添加4种氧化锌胶料中最低的;且胶料仅发生了磨粒磨损,未出现其他更为严重的磨损形式。文章对于添加不同类型氧化锌胶料摩擦磨损性能出现差异的原因进行了分析。分析结果表明,摩擦生热导致的硫化返原是造成胶料磨损程度不同的根本原因。即摩擦生热引起多硫键断裂及主链改性,造成胶料交联密度的下降,降低了胶料的耐摩擦磨损性能。

The friction and wear behavior of nitrile-butadiene rubber （NBR） filled with different kinds of zinc oxide （ZnO） were studied through ring-on-block tester under dry sliding. Based on samples preparation, the molecular structure of worn surface was measured by FT-IR. The results show that, compared with NBR containing conventional ZnO （c-ZnO）, nano-ZnO （n-ZnO）, and modified c-ZnO, NBR containing modified n-ZnO exhibits more outstanding wear resistance. Its wear loss is 0. 021 g, which is a quarter of wear loss of NBR containing e-ZnO. The frictional coefficient of NBR containing modified n-ZnO is the lowest （about 0.4）. There is no else worn form except for abrasive wear about NBR containing modified n-ZnO. The reason for the variation of friction and wear behavior of NBR containing different kinds of ZnO was discussed. The analysis results indicate that cure reversion induced by the generation of heat by friction is the root cause of the difference about friction and wear behavior. Namely, the decrease of crosslinking density results from breakage of multi sulfur bond and main chain modification caused by frictional heat, which results in reduction of the wear resistance.