EVA热压粘接PP/m-LLDPE的性能研究

Study on properties of hot-pressure bonding of EVA with PP and m-LLDPE

通过接触角和剥离强度的测试,研究了乙烯-醋酸乙烯共聚物(EVA)作为热熔胶热压粘接聚丙烯(PP)和茂金属催化线性低密度聚乙烯(m-LLDPE)的性能,并采用红外、扫描电镜分析了PP/EVA40-2/m-LLDPE复合材料剥离后的破坏区间。结果表明,EVA接触角较小,表面能较高,润湿性较好,采用EVA能有效改善PP/m-LLDPE的粘接性,EVA40-2与PP、m-LLDPE之间的剥离强度分别达到了14.7N/25mm和18.3N/25mm(PP和m-LLDPE剥离强度只有0.8N/25mm);另外,扫描电镜观察PP/EVA40-2/m-LLDPE的剥离表面以及剥离界面,发现在剥离界面处产生大量的无规则塑性形变并存在有少量破坏后的纤维丝,破坏区域发生在PP层和EVA层之间,剥离后,EVA表面凹凸不平,PP表面则较为平滑。

The properties of hot-pressure bonding of hot-melt adhesive EVA with PP and m-LLDPE were investigated by means of contact angle and peel strength tests,and the fractured zone of PP/EVA40-2/m-LLDPE composite after being peeled was analyzed by SEM and ATR-FTIR measurements.The results show that EVA,with properties of small contact angle,higher interface energy and better wettability,can effectively improve the bonding performance between PP and m-LLPDE,and the peel strengths of EVA40-2/PP and EVA40-2/m-LLDPE reach 14.7 N/25mm and 18.3 N/25mm,respectively,and the peel strength between PP and m-LLDPE is just only 0.8 N/25mm.Furthermore,the peeled surface and interface which were observed by SEM reveal that the interface emerges a large number of inconstant plastic deformation and a small amount of the damaged fibers,and the fracture occurs between PP-layer and EVA-layer.After peeling,the EVA surface is uneven but the PP surface is smooth.