聚乙烯丙烯酸与聚(2-乙基-2-噁唑啉)接枝共聚物的合成及表征

选用聚乙烯 丙烯酸 (EAA)为接枝母体 ,首先摸索出 2 乙基 2 唑啉阳离子开环聚合的规律 ,得到高转化率端基为活性离子的聚 ( 2 乙基 2 唑啉 ) (PEOX) ,再与EAA羟基侧基进行接枝反应 ,考察了开环聚合条件及接枝反应条件对接枝率的影响 ,在一定的条件下得到了接枝率 >2 5%的聚乙烯 丙烯酸与聚 ( 2 乙基 2 唑啉 )的接枝共聚物 (EAA g PEOX) .该接枝物用于聚对苯二甲酸丁二醇酯 /聚丙烯 (PBT/PP)共混体系中作相容剂 ,可提高两者的相容性 .

SYNTHESIS AND CHARACTERIZATION OF GRAFT COPOLYMER OF EAA WITH POLY(2-ETHYL-2-OXAZOLINE)

The title graft copolymer was synthesized by a two-step polymerization process. In the first step the monomer of 2-ethyl-2-oxazoline (EOX) was polymerized by cationic ring-opening polymerization with MeOTs as initiator in toluene. The prepolymer of poly(N-propionyl-ethylenimine) (PEOX) having living propagating end of oxazolinium ion in toluene was obtained with average molecular weight less than 10,000g/mol .Then the EAA (ethylene-acrylic acid copolymer) was grafted through the reaction of pendant carboxy group of EAA with the terminated living oxazolinium ion of PEOX in toluene.The effect of various parameters such as reaction condition of cationic polymerization, grafting reaction time and temperature, reactive group in EAA and PEOX molar ratio, and carboxy group content in EAA on grafting degree and average degree of polymerization in the graft chain were evaluated.It was found that there was a maximum grafting degree of graft copolymers, when the EAA/PEOX molar ratio is in the range of 5～6.The graft copolymer EAA-g-PEOX with grafting degree>25% can be obtained under some specific conditions,such copolymer can be used as compatiblizer in PBT/PP blends to improve the compatibility of the two phases and the mechanical properties.