纳米ZnO-RTV复合材料的制备与抗紫外性能研究

Research on Preparation of Nano ZnO-RTV Composite Material and Its Ultraviolet Resistance

为了提高室温硫化硅橡胶(RTV)抗紫外性能,本文通过钛酸酯偶联剂(PN)对纳米氧化锌(ZnO)进行改性,将其作为填料掺入RTV制备得到不同质量分数的纳米ZnO-RTV复合材料,对纯RTV和纳米ZnO-RTV复合材料进行紫外光加速老化实验,并对比分析纳米ZnO对RTV抗紫外性能的影响。结果表明:纳米ZnO能有效改善RTV的紫外光屏蔽性能,质量分数为1.0%的纳米ZnO-RTV复合材料紫外光屏蔽率的提升幅度高达72.63%;添加纳米ZnO后,RTV的电气强度略微提高;2500 h紫外老化后,纯RTV表面静态接触角的下降幅度、表面微观形貌所反映的老化程度都远大于纳米ZnO-RTV复合材料,这与老化前后RTV分子链Si-(CH_(3))2、Si-CH_(3)和C=O的变化情况相印证。同时,2500 h紫外老化后,纳米ZnO-RTV复合材料的热稳定性明显优于纯RTV。

To improve the UV resistance of room temperature vulcanized silicone rubber(RTV),we used titanate coupling agent(PN)to modify nano zinc oxide(ZnO),and then nano ZnO-RTV composites were prepared by doping different mass fraction of modified nano ZnO into RTV.The ultraviolet accelerated ageing experiments were conducted on pure RTV and nano ZnO-RTV composites,and the effect of nano ZnO on the ultraviolet resistance of RTV was compared and analyzed.The results show that nano ZnO can effectively improve the UV shielding performance of RTV,and the UV shielding rate of nano ZnO-RTV composite with 1.0%of ZnO can increase by 72.63%;after adding nano ZnO,the electrical strength of RTV is slightly improved.After UV ageing for 2500 hours,the decreasing amplitude of static con-tact angle and the ageing degree which reflected by surface micro-morphology of pure RTV are far greater than that of nano ZnO-RTV composite,it is verified by the changes of Si(CH_(3))2,Si-CH_(3),and C=O of RTV molecular chains before and after ageing.At the same time,after UV ageing for 2500 hours,the thermal stability of nano ZnO-RTV composite is significantly better than that of pure RTV.