采用差示扫描量热法(DSC)对树脂传递模塑(Resin Transfer Molding,简称RTM)工艺应用双酚A型乙烯基酯树脂体系的固化工艺进行研究,分析不同升温速率对固化体系的DSC曲线的影响,并利用Kissinger方程、Crane经验方程等固化动力学方程,确定该固化体系的反应动力学方程t=1-[1-5 584.65exp(-4 352.90/T)t]6.67,采用温度-升温速率(T-β)外推法从理论上得到体系的凝胶温度、固化温度和后固化温度等固化工艺参数为61.66,74.55,95.49℃。在实际应用中,由于内部反应热存在,适当降低使用温度。固化动力学方程及固化工艺参数对树脂传递模塑(RTM)工艺有重要意义。
Two kinds of 2.5D deep straight-joint structure ultra-high molecular weight polyethylene(UHMWPE)(twisted and original) fibers woven fabric reinforced epoxy resin composites were prepared by the hand lay-up method. Subsequently, the flexural property, microstructures, and failure mechanisms of the composites were also investigated. The average flexural strength of 2.5D deep bend-joint structure twisted fiber and original fiber woven fabric composites were 176.66 MPa and 204.45 MPa, respectively. The results of the characteristics indicated that the twist was the main factor which affected the flexural performance. Flexural property vitally relied on the strength of the fiber itself. Twist decreased the strength of the yarns, which meant that when the mechanical property of woven fabric reinforced composites was improved, the yarns must be kept straight in the woven fabric. The study are extremely valuable to guide the improvement of the mechanical property of the woven fabric reinforced composites.
