摘要
采用室温下为固体的3,5-二甲基吡唑(DMP)为封闭剂与对甲苯二异氰酸酯(TDI)反应,制备了可用于熔融挤出成型和注射成型聚氨酯复混配方的封闭型异氰酸酯单体。采用红外光谱,示差扫描量热分析和热重分析对反应过程及产物结构进行了研究。结果表明, 80℃下DMP可与TDI反应封闭完全,解封温度为180℃左右,解封产物室温即可与乙二醇反应发生加成反应,形成聚氨酯。
The blocked isocyanate monomer which could be used in melt extrusion molding and injection molding polyurethane compounding formula was prepared by reacting toluene diisocyanate(TDI)with blocking agent 3,5-dimethylpyrazole(DMP)which was solid at room temperature. The reaction process and product structure were studied by infrared spectroscopy,differential scanning calorimetry and thermogravimetric analysis. The results showed that TDI could be completely blocked with DMP at 80 ℃,and the deblocking temperature was about 180 ℃. The deblocked product could react with ethylene glycol by addition reaction at room temperature to form polyurethane.
引文
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