【摘要】 <正> 高分子弹性体受热与氧作用,会导致分子链的断裂或交联。Tobolsky采用间断和连续应力松弛对弹性体的热氧老化交联和降解过程进行了详细的研究。用应力松弛试验研究弹性体的热氧老化,除了化学引起松弛外,分子链滑移引起的物理松弛也必然掺入过程中,致使过程变得复杂了。更多还原

【Abstract】 The variation of dynamic modulus with frequency and aging time were determined during thermo-oxidation of the vulcanizatives of different cure systems and different carbon black fillers. According to the relationship among dynamic modulus,aging temperature and aging time,equation Et’/E’0=AeKt was used to calculate the rate constants and the related parameters of vulcanizatives on five samples of nitrile rubber-26 within 90-120℃. Arrhenius equation K = Ze-ERT was used to determine the apparent activation energies. It is definitely claimed that dynamic viscoe-lastic test is an excellent method to investigate the process of crosslinking and degradating during thermo-oxidation. It is also indicated that in order to evaluate the properties during thermo-oxidation of elastomers, the apparent activation energy must be combined together with the rate con-tants at different temperatures as well as the temperature coefficient of the rate constant.更多还原