EPDM-g-MS接枝率及MES冲击性能的研究

Study on Graft Ratio of EPDM-g-MS and Impact Properties of MES

用溶液接枝共聚法合成三元乙丙橡胶(EPDM)与甲基丙烯酸甲酯及苯乙烯(MMA-St)接枝共聚物(EPDM-g-MS),并与甲基丙烯酸甲酯与苯乙烯共聚物(MS树脂)熔融共混制备了耐老化黄变高抗冲材料(MES),研究了EPDM和MMA-St接枝共聚合反应条件与产物接枝率之间的关系及其对MS树脂的增韧作用的影响。结果表明,EPDM-g-MS的接枝率与MES的缺口冲击强度具有紧密的相关性。随着EPDM-g-MS接枝率的提高,MES的相结构由"取向"结构转变为"溶胀"结构,MES的断裂形变机理由空穴化转变为轻度剪切屈服,使得MES的缺口冲击强度显著提高。

EPDM-g-MS was synthesized by means of solution grafting copolymerization of methyl methacrylate （MMA） and styrene （St） onto ethylene-proplene-diene terpolymer （EPDM）. The high impact plastics （MES）, which had excellent resistance to weatherability and yellow discoloration and ageing property, were prepared by blending EPDM-g-MS with MS resin. The relationship between reaction conditions of the grafting copolymerization and were grafting ratio of the grafting products, and the effect of the grafting ratio on the toughening effect of MS resin studied. The results showed the graft ratio of EPDM-g-MS and the notched impact strength of MES were closely correlated. With ＂swelling＂ structure the increase of the grafting ratio of EPDM-g-MS, the phase structure of MES changed into from ＂orientation＂ structure, and the toughening mechanism of MES changed into slight shear yielding of matrix from the damage mode, which improved the notched impact strength of MES obviously.