作　　者： ; ; ;

机构地区： 华南理工大学

出　　处： 《涂料工业》 2007年第4期28-31,共4页

摘　　要： 提出了要想在薄膜蒸发器中分离出TDI,得到合格的聚氨酯固化剂产品,需要从合成固化剂入手,相对分子质量小、反应完全的聚氨酯固化剂更适合在薄膜蒸发器中进行分离,研究探讨了聚氨酯合成工艺。研究显示:分段升温反应有利于降低固化剂黏度;TDI和TMP的配比越大,固化剂黏度越小,但为了给后处理减小蒸馏负荷,确定TDI/TMP的质量比为4.6∶1;研究了酸碱度对反应的影响,反应体系偏碱性加速副反应,酸性较强也会加速副反应,研究显示加入少量磷酸有利于黏度的降低,提出了副反应抑制机理。合成的预聚物在分离过程中未见堵塞设备现象。 In order to distil free TDI from the PU curing agent with thin -film Evaporator, a suitable curing agent should be a small molecular weight and reacted thoroughly. It is shown that step temperature increasing will be favor to reduce the viscosity of curing agent, higher ratio of TDI/TMP will be also favor to viscosity reduction, but mole ratio 4. 6/1 is better for less distillation of TDI latter. The influence of pH value on reaction is discussed, high alkali or acidity will accelerate the side - reactions. Small amount of phosphoric acid will be favor to reduction of viscosity. Measures for inhibition of side - reactions is preposed. No plugging in evaporator happens during distillation of TDI from prepolymer.

关 键 词： 薄膜蒸发 聚氨酯 预聚物

领　　域： [化学工程]