微交联SAM共聚物对PC/ABS合金性能的影响

通过将微交联苯乙烯(St)–丙烯腈(AN)–马来酸酐(MAH)三元共聚物(SAM)、聚碳酸酯(PC)、丙烯腈–丁二烯–苯乙烯塑料(ABS)熔融共混,制备了一种低光泽PC/ABS合金,研究了SAM中MAH含量以及添加量对PC/ABS合金性能的影响。结果表明,SAM的添加可有效降低PC/ABS合金的光泽度,当其中MAH的含量超过12%后,其消光效果优于传统有机消光剂高交联苯乙烯-丙烯腈共聚物(SAN),随着MAH含量的进一步增加,光泽度下降不再明显,且缺口冲击强度和熔体流动速率(MFR)大大降低,最优的MAH含量为12%。随着SAM(MAH含量为12%)添加量的增加,PC/ABS合金的光泽度出现先明显降低后明显放缓的趋势,同时缺口冲击强度和MFR逐渐降低;当SAM添加量为7.5%时综合性能最佳,此时光泽度为5.3%,降低至空白样品的28.6%,缺口冲击强度为49kJ/m2,弯曲弹性模量为2512MPa,MFR为12g/(10min)。SAM降低PC/ABS合金光泽度的机理是由于其分子结构中交联SAN以及MAH基团与PC反应形成的支化交联复合物的双重作用使得合金表面粗糙度增加。目前该低光泽PC/ABS合金材料已经成功应用于多个汽车品牌的内饰件。

Effects of Micro-Crosslinking SAM Copolymer on Properties of PC/ABS Alloy

Low gloss polycarbonate (PC)/acrylonitrile-butadiene-styrene plastic (ABS) alloy was prepared through melting blend with micro-crosslinking styrene (St)-acrylonitrile (AN)-maleic anhydride (MAH) terpolymer (SAM),PC and ABS together. The effects of MAH content in SAM and SAM amount on the properties of PC/ABS alloy were studied. The results show that SAM can effectively reduce the gloss of PC/ABS alloy,and it is more efficient than traditional high cross-linked styrene-acrylonitrile (SAN),especially when MAH content is higher than 12%. Instead of more significant improvement of gloss reduction with further increasing of MAH content,the notched impact strength and melt flow rate (MFR) are obviously decreased,the optimal MAH content is 12%. The gloss of PC/ABS alloy decreases rapidly after increasing SAM amount (MAH content is 12%),but with further increasing,the gloss of alloy significantly slowes down,meanwhile notched impact strength and MFR keep decreasing. PC/ ABS alloy with SAM amount of 7.5% has the best comprehensive properties,which gloss is 5.3%,28.6% of blank sample,notched impact strength is 49 kJ/m2,flexural modulus is 2 512 MPa,and MFR is 12 g/(10 min). The mechanism of SAM for reducing gloss of PC/ABS alloy is that it can make the surface become more roughness with effects of both cross-linked SAN and branched compounds generated from reaction between MAH and PC. This kind of low gloss PC/ABS alloy material has been used for interior trim parts of multiple automobile brand vehicles.