聚氨酯复鞣填充剂的合成

蓖麻油经马来酸酐酯化得到羟基官能度为2.0～2.2的改性蓖麻油（MCO），将其作为多元醇成分与异佛尔酮二异氰酸酯（IPDI）、聚乙二醇1000（PEG1000）和二羟甲基丙酸（DMPA）等反应合成脂肪族耐光型聚氨酯复鞣填充剂(CPUF)。重点探讨了MCO/PEG1000、加料顺序、反应温度、DMPA用量和中和剂对乳液稳定性的影响。利用IR对聚氨酯复鞣剂的结构进行了表征。确定了工艺过程：改性蓖麻油首先同IPDI在70 ℃预聚40min，然后加入PEG1000和DMPA在80 ℃扩链100 min生成羟基终端的聚氨酯，其中m(MCO)∶m(PEG1000)=1∶1；中和剂选择三乙胺，聚氨酯复鞣剂中—COOH的质量分数为4%～5%。

Synthesis of polyurethane retanning agent

A new type of polyurethane retanning agent (CPUF) with excellent lightfastness was synthesized by the reaction of maleic anhydride modified castor oil(MCO) with hydroxyl functionality of 2.0～2.2，isophorone diisocyanate(IPDI)，poly(ethylene glycol) (PEG1000) and dimethylol propionic acid(DMPA).The effects of MCO/PEG1000，addition sequence，reaction temperatures，concentration of DMPA and neutralizer on the stability of CPUF emulsion were investigated. Fourier transform infrared spectroscopy(IR) was utilized to characterize CPUF structure. A preferred synthesis process was given as follows：MCO and IPDI prepolymerized at 70℃ for 40min , then chain extended with PEG1000 and DMPA at 80℃ for 100 min to get a hydroxyl terminated polyurethane，TEA was chosen neutralizer，m(MCO)∶m(PEG1000)=1∶1，the total content of —COOH was 4%～5%.