聚乙二醇/二醋酸纤维素共混物的相变行为

PHASE CHANGE BEHAVIOR OF POLYETHYLENE GLYCOL/DIACETATE CELLULOSE BLENDS

用静态热机械分析(TMA)、差示扫描量热(DSC)等方法研究了不同分子量聚乙二醇(PEG)与二醋酸纤维素(CDA)经溶液共混形成固态共混物的相变行为和热力学性质。当共混物中CDA质量比高于15%时,即使温度高于PEG熔点20℃～30℃,共混物中的PEG不再表现为液体状态,共混物表现出固态相变行为。PEG的分子量对共混物的相变行为无影响,当共混物中CDA质量比高于15%时,不同分子量的PEG与CDA形成固态共混物均可表现出固态相变性质。联合热重-差示热分析(TG-DTA)表明该共混物具有很好的热稳定性能。

The phase change behavior of polyethylene glycol(PEG) and acetate cellulose(CDA) blends prepared from mixed solution of acetone was investigated by means of DSC and TMA. It was found that when the CDA fraction in the blends was larger than 15%, PEG within the blends did not exhibit solidliquid phase change behavior as the pure PEG, but solidsolid one, even temperature was 20 ℃~30 ℃ higher than the melting point of polyethylene glycol. The blend of CDA and PEG with different molecular weight exhibited the same solidsolid phase change behavior as PEG was less than 85%. The measurement of the combined thermogravimetricdifferential thermal analyzer(TGDTA) indicated that blends exhibite good thermal stability.