THERMOREVERSIBLE GELATION OF CELLULOSE-ACETATE SOLUTIONS STUDIED BY DIFFERENTIAL SCANNING CALORIMETRY

被引:13
作者
ALTENA, FW
SCHRODER, JS
VANDEHULS, R
SMOLDERS, CA
机构
[1] Twente Univ of Technology, Enschede, Neth, Twente Univ of Technology, Enschede, Neth
关键词
CALORIMETERS; -; Applications; GELS; Manufacture;
D O I
10.1002/polb.1986.090240808
中图分类号
O63 [高分子化学(高聚物)];
学科分类号
070305 ; 080501 ; 081704 ;
摘要
Thermoreversible gels of cellulose acetate can be obtained by cooling concentrated cellulose acetate solutions in solvent-nonsolvent mixtures of dioxane and water. Upon heating the gels, endothermic effects were observed with differential scanning calorimetry. The heat effects are ascribed to the melting of a crystalline phase consisting of cellulose triacetate units. The endothermic peaks appear only after long aging periods of up to several days. Melting points generally decrease and heats of melting increase with increasing polymer concentration and with increasing nonsolvent content. The maximum degree of crystallinity is estimated as 8%. The kinetic effects of varying the water content in the solvent mixture are discussed.
引用
收藏
页码:1725 / 1734
页数:10
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