沙柳液化产物制备聚氨酯/环氧树脂互穿网络聚合物泡沫的性能

摘要

为研究沙柳液化产物制备聚氨酯/环氧树脂互穿网络聚合物(PU/EP IPN)泡沫的最佳发泡工艺,以沙柳液化产物和异氰酸酯(MDI)、环氧树脂(EP)为主要原料,水为发泡剂,辛酸亚锡为催化剂,纳米有机蒙脱土(OMMT)为形核剂进行试验,探讨了EP、MDI、辛酸亚锡、水和OMMT的添加量对泡沫材料表观密度和压缩强度的影响,并应用扫描电镜和热重分析仪对泡沫材料进行表征.结果表明:各主要原料和发泡助剂对泡沫轻质材料力学性能的影响由大至小分别为:环氧树脂添加量>异氰酸酯添加量>催化剂辛酸亚锡添加量>发泡剂水添加量>OMMT添加量;通过单因素和正交试验得到的优化工艺所制泡沫材料的表观密度为0.091 g/cm3,压缩强度为0.835 MPa;随着EP添加量的增加,IPN泡沫的热稳定性有所增加,添加OMMT对泡沫材料的阻燃性能有很大的提升.%Barren?ground willow(Salix psammophila)is a species of flowering plant in the willow family, which is one of the plenty resources planted in China,but is currently under?utilized due to some properties that limit its appli?cation. In this paper,branches of the barren?ground willow were converted into liquefied products containing the hy?droxyl?OH and reactive products by the biomass pyrolysis technology to replace petrochemical resources which was used to make polyurethane/epoxy IPN rigid foam. In order to obtain the optimum process parameters for the prepara?tion of barren?ground willow liquefaction products of polyurethane/epoxy resin interpenetrating polyurethane foam (PU/EP IPN),the certain proportion of liquefaction of barren?ground willow, isocyanate(MDI), epoxy resin(E?51)were used as the main raw materials,water as foaming agent,stannous octanate as catalyst,organic montmoril?lonite(OMMT)as nucleating agent,DMP?30 as curing agent for the experiments. Through several groups of the sin?gle factor test and the orthogonal test,the effects of different amount of EP,MDI,stannous octanate,water and OM?MT dosage on the foam apparent density and compressive strength were analyzed. The scanning electron microscope and Thermogravimetric(TG)analyzer were used to characterize the foam material.The results showed that the effects of main raw materials and foaming auxiliaries on the mechanical properties of foams were as the following order:the EP dosage>MDI dosage>stannous octanate dosage>blowing agent dosage>OMMT dosage. The apparent density of the foam obtained by the optimized process was 0.091 g/cm3,and the compressive strength was 0.835 MPa. The results of the TG test showed that the thermal stability of the IPN foam increased with the amount of the EP. The analysis re?sults of the limiting oxygen index showed that the OMMT can not only made the cell uniform,but also as a modifier to improve the flame retardant properties of the foam, while the excessive OMMT on the flame retardant effect was not obvious.