蔗渣纤维增强聚乳酸复合材料的制备及性能分析

Preparation and Properties of Bagasse Pulp Fiber-reinforced PLA Composites

以造纸用蔗渣纤维和聚乳酸(PLA)为主要原料,制备了蔗渣纤维增强聚乳酸复合材料,研究了Na OH(蔗渣纤维处理剂)的质量分数、复合材料中蔗渣纤维添加量及热压温度对复合材料力学性能的影响。结果表明,蔗渣纤维添加量为30%时,蔗渣纤维与PLA混合较好,复合材料较均匀;采用质量分数为5%的Na OH处理蔗渣纤维,可以溶解蔗渣纤维中的半纤维素、果胶等,使纤维更细化,比表面积增大,从而有效改善复合材料力学性能;热压温度为170℃时,PLA的流动性有助于改善蔗渣纤维在PLA中分散的均匀性,且不会使蔗渣纤维和PLA降解。在此最优条件下,复合材料的拉伸强度和冲击强度分别达到最大值。

Bagasse pulp fiber-reinforced PLA composites was fabricated with bagasse pulp fibers and PLA, effects of mass fraction of bagasse fibers, modifier （NaOH） concentrations, as well as the hot-pressing temperature on composites＇ mechanical properties were investigated. The results showed that bagasse fibers could be uniformly mixed with PLA when its mass fraction was 30%, treatment of bagasse fibers with 5% NaOH could dissolve the hemicellulose and pectin of the bagasse fibers which led to further refine bagasse fibers, and increased its specific surface area, and finally improved composites＇ mechanical properties effectively. At 170℃ the flowability of PLA was very good to help im- prove the bagasse fibers dispersion in PLA uniformly, the bagasse fibers and PLA would not be decomposed at that temperature. The impact and tensile properties of the composites reached the maximum values of 44. 6 MPa and 10. 5 MJ/m2 respectively under such optimal prepara- tion conditions.