热压罐始加压预浸料用高温树脂体系的制备与性能研究

PREPARATION AND PROPERTIES OF HIGH TEMPERATURE RESISTANT RESIN SYSTEM FOR HOT PRESSURE TANK INITIAL PRESSURE PROCESSING PREPREG

本文设计合成了一种噁唑烷酮环结构高温韧性环氧树脂(OXEP),采用化学流变剂调节和OXEP改性四官能团环氧树脂,制备符合热压罐始加压成型工艺的热熔法专用树脂体系。研究了OXEP含量对树脂体系拉伸性能、韧性和耐热性的影响,利用热压罐始加压成型工艺制备碳纤维复合材料,并与常规热压罐工艺复合材料力学性能进行对比。结果表明:化学流变剂反应120 min可达到始加压工艺要求;OXEP的加入可有效改善固化树脂的力学性能,加入OXEP改性环氧32 phr时,改性树脂的拉伸强度和冲击强度相对于未改性树脂分别提升了29%和73%,断裂韧性提高了3.3倍;改性树脂试样断裂面微观形貌较为粗糙,且有较深的沟壑,断裂耗散的能量较多,增韧效果明显;热压罐始加压热熔法复合材料力学性能优于常规热压罐工艺,复合材料0°拉伸强度和层间剪切强度提升明显,分别提高了34.5%和38.6%。

A high temperature resistant toughened epoxy resin(OXEP)was designed and synthesized.A tetrafunctional epoxy resin were modified by chemical rheological agent and OXEP to prepare a hot melt resin system which conformed to hot pressing tank initial pressure forming process.The effect of OXEP content on tensile,toughness and heat resistance of the resin system was studied.Mechanical properties of composites prepared by hot pressing tank initial pressure forming process and traditional process were compared.The results showed that the reaction time of chemical rheological agent should be controlled at 120 min.The addition of OXEP can effectively improve the mechanical properties of the cured resin.When OXEP modified epoxy is added at 32 phr,the tensile strength and impact strength of the modified resin are increased by 29%and 73%,respectively,and the fracture toughness is improved by 3.3 times.Tough fracture surface with deep ravines indicated high fracture energy dissipation,and thus remarkable toughening effect.The mechanical properties of the autoclave-compressed hot-melt composites are better than those of the conventional autoclave.The 0°tensile strength and shear strength of the composites are significantly improved,which are increased by 34.5%and 38.6%,respectively.