相容剂对rPET/mLLDPE共混物性能的影响

以回收聚对苯二甲酸乙二醇酯(rPET)为基体材料,茂金属线型低密度聚乙烯(mLLDPE)为共混材料,马来酸酐接枝线型低密度聚乙烯(LLDPE-g-MAH)、丙烯酸酯复合接枝苯乙烯-丁二烯弹性体为相容剂,制备了rPET/mLLDPE共混物。采用DSC和SEM分析了相容剂对共混物结晶性能及断面结构的影响,并检测了共混物的力学性能。结果表明:mLLDPE的加入使得rPET/mLLDPE共混物的熔体结晶峰向右移动,结晶温度提高了29.03℃;相容剂的加入使得共混物中rPET的玻璃化转变温度向低温方向移动,rPET与mLLDPE相容性增强;含3%LLDPE-g-MAH的rPET/mLLDPE共混物中,MAH基团与rPET中的羟基发生接枝反应,相界面模糊,rPET与mLLDPE界面黏结力增强,与纯rPET相比,其断裂伸长率提高了93.73%,缺口冲击强度提高了54.6%。

Effect of Compatibilizers on Properties of rPET/mLLDPE Blend

Taking recycled PET (rPET) as matrix material, mLLDPE as disperse phase, methacrylate-styrene- butadiene graft copolymer elastomer and maleic anhydride functionalized linear low density polyethylene (LLDPE-g-MAH) as compatibilizers, the rPET/mLLDPE blend was prepared. The effects of compatibilizers on crystallization behavior, fracture surface morphology and mechanical properties of rPET/mLLDPE blend were investigated by DSC, SEM and mechanical property test. The results show that the crystallization temperature for the rPET/ mLLDPE composite increases by 29.03 ℃ with the addition of mLLDPE; the glass transition temperature of rPET in the blend shifts to lower temperature with the addition of compatibilizer, and the compatibility between rPET and mLLDPE is improved; there exists grafting reaction between the hydroxyl groups of rPET and MAH groups with the addition of 3% LLDPE-g-MAH into rPET/mLLDPE blend, and the interaction between rPET and mLLDPE is improved; compared with pure rPET, the elongation at break of the blend increases by 93.73%, and the impact strength increases by 54.6%.