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BF_3络合的丙烯酸乙酯(EA)与丙烯(P)在25℃进行自由基共聚。聚合速率和引发剂浓度的平方根成直线关系。链转移剂CCl_4可显著影响共聚物的[η];溶剂的介电常数越小,共聚反应速率越大;两种单体浓度相等时共聚反应速率最大。~1H-NMR和 _13C-NMR表明,当[EA·BF_3]/[EA·BF_3]+[P]>O.5时所得共聚物为富于EA的无规共聚物。实验数据表明,共聚反应按三元络合物与二元络合物的无规共聚机理进行,当[EA·BF_3]/[EA·BF_3]+[P]<0.5时,得到交替共聚物,共聚反应按三元络合物均聚机理进行。UV光谱测得了戊烯-1(丙烯的同系物)与EA·BF_3三元络合物的存在,这对三元络合物的均聚机理是有力的证据。
BF_3-complexed ethyl acrylate (EA) was copolymerized with propylene (P) at 25 ° C. The polymerization rate is linear with the square root of the initiator concentration. The chain transfer agent CCl_4 can significantly influence the [η] of the copolymer. The smaller the dielectric constant of the solvent is, the higher the copolymerization rate is. The copolymerization rate is the highest when the two monomers are equal. ~ 1H-NMR and _13C-NMR showed that the copolymer obtained was an EA-rich random copolymer when [EA · BF 3] / [EA · BF 3] + [P] & gt; The experimental data show that the copolymerization reaction proceeds according to the random copolymerization mechanism of ternary complex and binary complex. When [EA · BF_3] / [EA · BF_3] + [P] <0.5, Copolymerization by ternary complex homopolymerization mechanism. UV spectroscopy measured the existence of pentene-1 (propylene homologues) and EA · BF_3 ternary complex, which is strong evidence for the homopolymerization mechanism of the ternary complex.