酸酐化LLDPE/PS增容母料的制备及其应用

摘要

通过Friedel-Crafts烷基化反应和聚烯烃熔融接枝马来酸酐(MAH)技术,制备了酸酐化线型低密度聚乙烯(LLDPE)/聚苯乙烯(PS)增容母料,并用该母料增容LLDPE/PS/聚酰胺(PA)6三元共混物,考察了母料用量对LLDPE/PS/PA 6三元共混物结构及性能的影响.结果表明:酸酐化增容母料中主要含有MAH接枝LLDPE-g-PS与MAH接枝LLDPE,可用于提高LLDPE与PS和PA 6的相容性;该母料能有效增容LLDPE/PS/PA 6三元共混物,使三相之间界面作用增强,分散相粒径显著减小,力学性能提高;随着母料用量增加,共混物的熔体流动速率下降,LLDPE的结晶温度上升,而PA 6的结晶温度和PS的玻璃化转变温度呈下降趋势;当母料用量为8 phr时,共混物的力学性能和耐热性能最佳.%Maleated line low density polyethylene (LLDPE)/polystyrene (PS) compatibilized master batch was prepared via the combination of Friedel-Crafts alkylation and polyolefin melt-grafting maleic anhydride (MAH).Then the master batch was used to compatibilize LLDPE/PS/polyamide 6 (PA 6) ternary blends.The impact of the amount of the master batch on the structure and properties of LLDPE/PS/PA 6 ternary blends were investigated.The results reveal that the maleated master batch is mainly composed of (LLDPE-g-PS)-g-MAH and LLDPE-g-MAH,which can improve the compatibility of LLDPE with PA 6 and PS.It can compatibilize effectively the LLDPE/PS/PA 6 ternary blends,enhance the interfacial interaction between phases,the dispersed particle size decreases significantly and the mechanical properties of the ternary blends are also improved.The melt flow rate of ternary blends decreases,the crystallization temperature of LLDPE rises,and the crystallization temperature of PA 6 and glass transition temperature of PS descend with the increasing of the master batch.The optimal mechanical and thermal properties of the ternary blends are obtained when the master batch is 8 phr.