蓖麻油TDI聚氨酯预聚体的制备

利用双键含量、异氰酸酯根(-NCO)含量和游离甲苯二异氰酸酯(TDI)含量的测定,研究了反应条件对蓖麻油聚氨酯预聚体(CO-PU)合成的影响。结果表明,随着反应温度的升高,CO-PU中剩余-NCO的含量逐渐减少,游离TDI含量逐渐降低;增加nNCO/nOH,CO-PU中剩余-NCO和游离TDI含量增大;延长反应时间,-NCO含量减小;加入二丁基二月桂酸锡(DBTDL)后,酯化反应速率加快,体系中-NCO含量明显降低。在-NCO与羟基的反应过程中双键比较稳定,CO-PU中的双键含量基本不变。

Preparation of castor oil TDI polyurethane prepolymer

In this paper,effect of reaction conditions on synthesis of castor oil-based polyurethane prepolymer(CO-PU) was studied by testing the contents of double bond,isocyanate(NCO) groups and free toluene diisocyanate(TDI).The results showed that the remaining content of NCO and free TDI in CO-PU decreased gradually with increasing temperature,the remaining content of NCO and free TDI of CO-PU increased with increasing the ratio of nNCO/nOH;the remaining NCO content in CO-PU decreased by extending reaction time;esterification rate accelerated and the content of NCO in the system decreased obviously after adding organic metal catalysts of dibutyltin dilaurate(DBTDL).The double bonds were relatively stable during reacting of NCO and hydroxyl groups and the content of double bonds of CO-PU was basically unchanged.