椰壳纤维/玻璃纤维增强酚醛树脂复合材料的性能研究

Properties of Coir Fiber/Glass Fiber Blended Phenolic Resin Composites

以椰壳纤维和玻璃纤维为增强材料,以酚醛树脂为基体,经非织造工艺制备预成型件,采用模压成型工艺制备不同纤维体积分数的复合材料,分别对复合材料的力学性能、吸湿性能及耐热性能进行测试。结果表明:提高椰壳纤维/玻璃纤维含量可有效提高复合材料的拉伸强度和拉伸模量。当纤维含量达60%时,复合材料的拉伸性能达到最大。当纤维含量达70%,复合材料的抗弯性能最好。对椰壳纤维材料碱预处理能够有效提高材料的力学性能。综合成本及材料特性,材料最优制备工艺为椰壳纤维/玻璃纤维的体积比为1∶1,纤维含量为70%。当纤维含量为70%,椰壳纤维/玻璃纤维增强酚醛树脂复合材料的冲击强度最高为1.62 J/mm^(2)。椰壳纤维的添加提高了材料在自来水、蒸馏水和海水等介质中的吸湿效率,但降低材料在250~550℃区间的热稳定性。

With coconut shell fiber and glass fiber as reinforcing materials,phenolic resin as matrix,the preforms were prepared by nonwoven process,and the composites with different volume fractions of reinforcing fibers were prepared by molding process.The mechanical properties,moisture absorption properties and heat resistance of the composites were tested respectively.The results show that the tensile strength and tensile modulus of the composites can be effectively improved by increasing the content of coconut shell fiber/glass fiber.The tensile properties of the composite reaches the maximum when the fiber content reaches 60%.When the fiber content reaches 70%,the bending resistance of the composite is the best.Alkali pretreatment of coconut shell fiber can effectively improve the mechanical properties of the material.Considering the cost and material characteristics,the optimum preparation process of the material is that the volume ratio of coconut shell fiber/glass fiber is 1∶1,and the fiber content is 70%.When the fiber content is 70%,the maximum impact strength of coconut shell fiber/glass fiber phenolic resin composite is 1.62 J/mm^(2).The addition of coconut shell fiber improves the moisture absorption efficiency of the material in tap water,distilled water and seawater,but reduces the thermal stability of the material at 250~550℃.