碳纤维布增强酚醛环氧树脂的力学性能

Mechanical properties of phenolic epoxy resin reinforced with carbon fiber cloth

酚醛树脂具有较好的机械加工性能以及极佳的耐热性能,但是酚醛树脂性脆,韧性差,采用环氧树脂对其进行共混改性可以提高酚醛树脂的韧性,但是会损失一定的热性能.以碳纤维布作为增强材料,酚醛树脂,环氧树脂作为基体,经过浸渍,层压成型等工艺,制得碳纤维布增强酚醛环氧树脂复合材料.通过比较不同质量分数的酚醛/环氧树脂质量比所制得的材料的力学性能,热性能及扫描电镜表征出的复合材料的微观结构,得出在环氧树脂质量分数为25%时,该复合材料的弯曲强度达到262.5 MPa,冲击强度达到62.3 k J·m-2,相对于没有加入环氧树脂的碳纤维布增强酚醛环氧树脂复合材料,分别提高了23%和185%.热形变温度达到158.8℃,相对于没有加入环氧树脂的复合材料减少了13%.综合来看,环氧树脂质量分数在25%时,碳纤维布增强酚醛环氧树脂复合材料具有最佳的综合性能.

Phenolic resin owns favorable machining property and excellent heat resistant property, but it has brittleness and poor toughness. Using epoxy resin to conduct the blending modification to improve the toughness of phenolic resin, the thermal property of the resin will get a loss. The phenolic-epoxy resin composite reinforced by carbon fiber cloth was prepared by taking carbon fiber cloth as the reinforced material and phenolic resin and epoxy resin as the matrix via dipping and laminated, molding,etc. By comparing the mechanical property, thermal property and the microstructure of the composite prepared by different phenolic/epoxy mass fractions, we found that when the mass fraction of epoxy resin is 25%, the flexture strength of the composite reaches 262.5 MPa and the impact strength reaches 62.3 k J·m-2, which increases by 23% and 185%respectively compared with the phenolic-epoxy resin composite reinforced by the carbon fiber cloth without adding epoxy resin. Meanwhile,the thermal distortion temperature is 158.8℃, decreasing by 13% compared with the composite without adding epoxy resin. In general, the phenolic-epoxy resin composite reinforced by the carbon fiber cloth owns the best comprehensive properties when the mass fraction of epoxy resin reaches25%.