【摘要】 目前已商业化的RIM体系主要是聚氨酯体系。本文研究了一种由三官能度以上的聚醚多元醇和液态MDI、乙二醇作扩链剂、二月桂酸二丁基锡(?)/或三乙撑二胺为催化剂组成的聚氨酯体系的流变性能;用自行研制的一种共轴圆筒式粘度计测定反应物料在凝胶化以前粘度随时间的变化;并据以确定对指导加工过程有重要意义的凝胶时间。结果表明:原料温度的上升、催化剂和扩链剂用最的增大,均可使凝胶时间缩短;有机锡催化剂比胺的催化活性高得多。更多还原

【Abstract】 RIM systems Which have now been commercialized are mainly polyuretnane systems. One morheology of polyurethane systems which consists of a polyether polyol (functionality>3), a liquid form of MDI, ethylene glycol as chain extender, dibutyltin dilaurate or triethylenediamine as catalysts is studied in this article. A concentric cylindric viscometer determined that the viscosity of the reaction mixture, would change with the time before gelation, and the gel time that is important to guide the processing was thus fixed. The results show that the gel time can be shortened with the rise in temperature of materials and the increase in dosage of a catalyst and chain extender. The catalytic activity of organotin catalysts is much higher than that of amine.更多还原