增韧剂改性聚乳酸材料性能研究

Study on the Properties of Polylactic Acid Modified by Toughening Agent

聚乳酸(PLA)材质韧性较差等缺陷限制了其在工业上的许多应用,为进一步拓宽PLA的应用范围,需对其进行适当的改性使其满足不同使用需求。本文主要通过改变PLA中聚己内脂(PCL)和聚己二酸/对苯二甲酸丁二酯(PBAT)两种可降解的增韧剂的添加量(0、5%、10%、15%、20%),探究其含量对PLA基复合材料熔体质量流动速率、热性能、力学性能等有关性能的影响,优化PLA材料增韧剂的选择与添加量。结果表明,同等添加量的PCL与PBAT相比,PCL的熔体流动性及热性能均展现出更优异的性能。同等含量的PCL改性PLA的拉伸强度和弯曲强度均优于PBAT,15%的增韧剂都可使复合材料的耐冲击强度达到最高,PCL改性PLA的冲击强度达到14.93 kJ/m~2,相比于纯PLA提高了70%。

The poor toughness of polylactic acid(PLA)material had limited many applications in industry.In order to further expand the application range of PLA,appropriate modification was carried out to meet different requirements.In this paper,by changing the addition amounts of polycaprolactone(PCL)and polyadipate/butylene terephthalate(PBAT),two degradable tougheners in PLA(0%,5%,10%,15%,20%),the influences of their contents on melt rate,thermal properties,mechanical properties and other related properties of PLA matrix composites were explored,and the selection and addition amount of PLA material tougheners were optimized.The results show that the melt fluidity and thermal properties of PCL show better performance than PBAT with the same amount of PCL.The tensile and bending strength of PCL modified PLA with the same content is better than PBAT.Even 15%toughening agent can make the impact strength of the composite reach the highest.The impact strength of PCL modified PLA reaches 14.93 kJ/m~2,which is 70%higher than that of pure PLA.