纤维素/聚乙二醇共混物相变行为及在DMSO/PF和DMAC/LiCl中相容性的研究

Phase change behavior of polyethylene glycol-cellulose blends and their miscibilities in DMSO/PF & DMAC/LiCl

纤维素和聚乙二醇在二甲基亚砜／多聚甲醛（DMSO/PF）、二甲基乙酰胺／氯化锂（DMAC/LiCl）溶剂体系中表现出不同的相容性，同时再生共混物也表现出不同的相变行为。在DMSO体系下，聚乙二醇和纤维素在溶液状态下具有较好的相容性，再生共混物的相变焓较大，相变性质为固一固态相转变；而在DMAC／LiCl体系中，纤维素和聚乙二醇的相容性较差，再生后共混物的相变焓很小，相变性质为固一液相转变。纤维素在该两溶剂体系中的溶解机制及分子间的相互作用状态不同是导致它和聚乙二醇的共混相容性差异和再生共混物相变行为不同的原因。

The phase chang behavio of polythylen glycol(PEG)/celluose blends prepared from the solutio of DMAC/LiCl and those from the solutions of DMSO/PF were found completelydifferent.The differences of the phase change boehaviors bo haavio of the blends axe Probah ds to theirthe ndscaibilities in the two solven systems. Ih DMAC/CiCl, the ndscthlity of the two poly-mere is limited,PEC widri the blends obtaind meted into litwd at itS melting poin,just as aPare PEG does. However, in DMSO/P, the nhacthility of the two polyzners is high, the blends ob-tained whthited a solid - solid phase change transition,insead of the fusion in the instead of the fhaion in the case ofDMAC/LiCl.The differences of miscibilities and phase change behaviors of the blends are pre-sumed to be the result of the fifferent dissolving mechanisms and the different intermolecular reac-tions in these two solutions.