凹凸棒土的表面处理及在硅橡胶中的应用研究

Study on Surface Treatment of Attapulgite and Its Application in Silicone Rubber

以纳米凹凸棒土(AT)为补强剂,采用机械共混法对甲基乙烯基硅橡胶(MVQ)进行填充,制备了具有优异力学性能和高耐热性能的纳米AT/MVQ复合材料。具体考察了填料纳米AT和硅烷偶联剂的用量、改性方式等对材料的影响,同时通过热分析(TG、DTA)研究其耐热性能。结果表明,AT对MVQ具有较好的补强性能,且经湿法改性后有利于改善复合材料的性能,提高材料的耐热性能。力学性能测试表明,填料用量为10phr时,采用湿法改性AT填充所得复合材料的拉伸强度增加了19.5%。热分析表明,相比于生胶,填充改性AT的复合材料的初始分解温度提高了41.1℃。流变性能测试结果表明,通过改性可以增强AT与MVQ分子之间的界面结合力,降低了"Payne效应"。

Methyl-vinyl silicone rubber （MVQ） was reinforced with nano-attapulgite（AT） as reinforcing filler. Even more excellent mechanical and thermal stability reinforced silicone rubber nanocomposite was prepared by means of mechanically compounding. The effect of the addition level of nano-attapulgite and silane coupling reagent, the different modification technology of attapulgite on mechanical performance of composite were investigated in detail, and the thermal stability was also studied with TG-DTA. The results showed that nano-attapulgite exhibited the better reinforcement to the MVQ, and using the wet modified nano-attapulgite as filler could improve the mechanical properties and thermal stability of the nanocomposites. According the mechanical properties test, it was inferred that the tensile strength of the nanocomposites filled with the wet modified nano-attapulgite increased by 19.5% compared with MVQ when the addition level was 10 phr. Data from TG and DTA indicated that the thermal initial decomposition temperature of the composites increased by 41.1 ℃ compared with MVQ. The results of the rheological properties test showed that surface modification could promote adhesion between nano-attapulgite and MVQ molecules, and the so called ＂Payne effection＂ was reduced.