聚乙二醇/聚乙烯醇固-固相变材料等温结晶动力学及熔融行为研究

Confined Isothermal Crystallizing Kinetics and Melting Behavior of Polyethylene Glycol(PEG) / Poly (vinyl alcohol) (PVA) Solid-Solid Phase Change Materials

采用接枝共聚法将聚乙二醇(PEG)接枝到聚乙烯醇(PVA)主链上,得到了系列性能稳定的PEG/PVA高分子固固相转变材料,利用DSC法对PEG在受限状态下等温结晶及结晶后的熔融行为进行了研究。结果表明:PEG和共聚体系的Avrami指数n在2左右,说明结晶生长方式是二维生长,速率常数Z随温度升高而减小,样品的成核属非均相依热成核方式。结晶后的等温熔融行为表明PEG出现熔融双峰,共聚体系只显示一个与PEG低温峰相对应的吸收峰,该峰的高温侧出现肩峰,且随Tc升高而变得明显。

New serials of PVA-g-PEG graft copolymers with the characterization of solid-solid phase change were prepared. The isothermal crystallizing kinetics and meliting behavior of PEGwere discussed by DSC. The results showed that Avrami parameters were all in 2 their growth pattern were twodimensional crystal growth and Z decreased with increasing temperature. The melting behavior showed that PEG turned up double peaks, PVA-g-PEG graft copolymers turned up only one distinct peak correspoding to lower peak of PEG and acromions were appeared at high-temperature side, and became more clearer when T0 increased.