氢化羧基丁腈橡胶/AO-2246复合材料阻尼性能研究

以氢化羧基丁腈橡胶(HXNBR)为基体,加入极性有机小分子2,2'-亚甲基双-(4-甲基-6-叔丁基苯酚)(AO-2246)进行改性,制取了HXNBR/AO-2246复合材料,对其阻尼性能进行研究。结果表明,AO-2246质量分数在40%以内时,随其用量的增加HXNBR/AO-2246复合材料阻尼性能逐渐提高,在40%时状态最佳,此时损耗因子(tanδ)峰值为2.21,对应玻璃化转变温度(T_g)为24.9℃,tanδ>0.3的有效阻尼温域为32.6℃。HXNBR/AO-2246复合材料阻尼性能的提高是基于HXNBR中氰基(—CN)和羧基中的C=O与AO-2246中的羟基(—OH)形成了氢键网络作用,以及AO-2246较大侧基所带来的位阻效应。同时,随着AO-2246用量逐渐增加,小分子达到饱和并开始自聚结晶,材料出现两相结构,在AO-2246质量分数为50%时,过多的小分子使得材料阻尼性能下降,但对应Tg继续往高温方向移动。

Study on damping property of HXNBR/AO-2246 composite

The HXNBR/AO-2246 composites were prepared with hydrogenated carboxyl nitrile rubber(HXNBR)as the substrate,and the polar organic small molecule 2,2’-methylenebis-(4-methyl-6-tert-butylphenol)(AO-2246)was added for modification.The damping properties were studied.The results shown that the damping performance of HXNBR/AO-2246 increased with the increase of AO-2246 mass ratio within 40%.The damping performance was best with the loss factor(tanδ)peak was 2.21 and corresponding glass transition temperature(T_g)was 24.9℃,the effective damping temperature range of tanδ>0.3 was 32.6℃when mass fraction of AO-2246 was 40%.The improvement of the damping property of HXNBR/AO-2246 was based on the cyano group(—CN)and the C=O in carboxyl group in HXNBR formed a hydrogen bond network with hydroxyl group(—OH)in AO-2246,and bringed the steric effect of the larger side group of AO-2246.At the same time,with gradually increasing the AO-2246,the small molecules reached saturation and begin to self-polymerizing and crystallized.The material exhibited a twophase structure.When increasing to 50%,too many small molecules caused the damping property of the material to decrease but the corresponding Tg continued to move toward the high temperature.