Lignin/EVA复合材料的相容改性研究

Study on the Improvement of Compatibility in Lignin/EVA Composites

Lignin/EVA复合材料由EVA与碱木质素(Lignin)在转矩流变仪中共混后经平板硫化仪热压制得。主要研究了不同VA含量的EVA对Lignin/EVA复合材料性能的影响,扫描电子显微镜(SEM)和热分析(DSC)测试结果表明, VA含量较高的EVA与Lignin的相容性更好;力学性能测试结果表明VA含量高的Lignin/EVA复合材料的力学性能优于EVA,而VA含量低的Lignin/EVA复合材料不敌纯EVA;针对相容性不理想的Lignin/EVA复合材料,研究了不同相容剂硬脂酸(SA)、环氧树脂E44 (E44)、乙烯-醋酸乙烯酯共聚物接枝马来酸酐(EVA-g-MAH)、聚乙烯接枝马来酸酐(PE-g-MAH)对复合材料力学性能的影响。SEM结果表明,上述相容剂均在一定程度上改善了Lignin与EVA基体之间的相容性;从力学性能上看,改善相容性效果最佳的是E44,与未添加相容剂的Lignin/EVA复合材料相比,添加了E44的Lignin/EVA复合材料拉伸强度增加了10.4%。

Lignin/EVA composites were prepared by mixing EVA with alkali lignin（Lignin） in a torque rheometer.The effects of different VA content of EVA on the properties of Lignin/EVA composites were investigated. The results from scanning electron microscopy（SEM） and thermal analysis（DSC） testing showed that EVA with higher VA content had better compatibility with lignin. The mechanical properties of Lignin/EVA composites with higher VA content also were better than those of pure EVA while the Lignin/EVA composites with lower VA content were worse than those of pure EVA. Lignin/EVA composites with different compatibilizers including stearic acid（SA）, epoxy resin E44（E44）, ethylene vinyl acetate copolymer grafted maleic anhydride（EVA-g-MAH） and polyethylene dendrite maleic anhydride（PE-g-MAH） composites were studied. SEM results showed that these compatibilizers could improve the compatibility between lignin and EVA matrix. The addition of compatibilizers could also improve the mechanical properties of the composites while the tensile strength of the Lignin/EVA composites with E44 increased by 10.4% compared to the one without addition of compatibilizer.