Effect of the temperature of polyurethane dissolution on the mechanism of wet-casting membrane formation
出版日期:2003-03-01 00:00:00
著者:Cheng, Liao-ping; Huang, Yen-shih; Young, Tai-horng
單位:淡江大學化學工程與材料工程學系
出版者:Elsevier
著錄名稱、卷期、頁數:European polymer journal 39(3), pp.601-607
摘要:An analysis of data from scanning electron microscopy (SEM), gel permeation chromatography (GPC) and differential scanning calorimetry (DSC) for two series of polyurethane membranes is presented. Membranes were prepared by direct immersion of the casting solution of polyurethane, dissolved in dimethyl formamide at different temperatures, into either water or 1-octanol bath at 25 °C. Depending on the temperature of polyurethane dissolution, a gradual variety in the membrane structure was observed by SEM. As the temperature of polymer dissolution was increased, the membrane structure changed from dense to cellular or particulate morphologies. On the basis of the GPC and DSC results, polyurethane molecular weight decreased but the degree of microphase separation caused by clustering of some of the soft and hard segments into separate domains in the membrane increased with increasing the temperature of polymer dissolution. It is thus proposed that the change in membrane structure is due to the variation of molecular weight of polyurethane, which in turn can change polymer chain mobility during membrane formation. In addition, the extent of microphase separation was described and related to the particulate morphology when 1-octanol was used as the nonsolvent.
關鍵字:Polyurethane;Dissolution temperature;Particulate membranes
語言:en
ISSN:0014-3057
期刊性質:國外
審稿制度:否
國別:GBR
出版型式:紙本