【摘要】 采用接枝共聚法将具有相变特征的聚乙二醇(PEG)接枝到具有较高熔点的聚乙烯醇(PVA)主链上,得到系列性能稳定的PEG/PVA高分子固固相转变材料,利用DSC法对PEG受限状态下非等温结晶行为进行研究。结果表明,随着降温速率增大,峰值温度Tp向低温移动,半结晶时间t1/2逐渐减小,结晶速度G逐渐增大。接枝共聚体系Tp低于纯PEG4000,半结晶时间t1/2大于纯PEG4000。对于接枝共聚体系而言,接枝率对半结晶时间t1/2影响不大,共聚体系中的Avrami指数大多数在2~3之间,比等温结晶更加复杂。运用Jeziorny方法和莫志深方法比较适用于本体系非等温结晶动力学的研究。更多还原

【Abstract】 New serials of PVA-g-PEG graft copolymers with the characterization of solid-solid phase change were prepared.The confined of PEG in PVA-g-PEG graft copolymers was investigated by differential scanning calorimetry.The crystallization kinetics was discussed by several methods.The results showed that the lower temperature peak(Tp) shifted to the lower temperature and its peak intensity also decreased with increasing the cooling rates,t1/2 decreased and G increased.The Tp of graft copolymers were lower than pure PEG and t1/2 of which were higher than pure PEG.The graft ratio had litter influence on t1/2.Avrami parameters were all in 2-3.The results also showed that both Jeziorny method and the new method combing the Avrami equation and Ozawa equation by Mo et al.described this system very well.更多还原