利用DSC、流变仪和能量损耗仪等测试仪器,系统研究了碳纳米管加入到聚苯乙烯基体中后对不同长度聚苯乙烯分子链运动的影响.结果表明,碳纳米管加入到聚苯乙烯中后对聚苯乙烯的玻璃转变和液-液转变都产生了影响.碳纳米管的加入引起自由体积的增加只在一个很小的范围内影响了分子链段的运动,当质量分数为0.1%的碳纳米管加入时,链段运动速度增加,玻璃转变温度明显向低温方向移动;而由于范德华力的存在,高分子链会在碳纳米管表面选择吸附,从而使得整链运动时,参与运动的链单元尺寸降低,所以造成了整链运动时链间的耦合降低了.
In this paper, the dynamics of polystyrene chain was studied by DSC, rheology and energy dissipation spectrum. It was shown that both the glass transiton and the liquid-liquid transition all changed for the appearance of MWNT in MWNT/PS composites. The appearance of free volume aroused by MWNT fillers influenced the mobility of segments in a small area and the speed of segment mobility increased leading to the decrease of glass transition temperature when 0.1 wt% added into polystyrene matrix. For the existence of van der Waals forces, the polymer chains adsorped selectively on the surface of nanotube which decreased the length of polymer chain that took part in the mobility of whole chain, i. e. , the intermolecular coupling decreased.