含氟丙烯酸酯与苯乙烯共聚物的RAFT合成及表征

通过可逆加成-断链链转移(RAFT)溶液聚合,以三硫代碳酸酯为RAFT试剂,偶氮二异丁腈(AIBN)为引发剂,1,4-二氧六环为溶剂,制备甲基丙烯酸(2,2,2-三氟)乙酯(TFEMA)和苯乙烯(St)共聚物.详细研究了不同引发剂的用量、RAFT试剂与引发剂摩尔比以及聚合温度等实验条件对聚合反应过程的影响.通过GPC、FTIR测试共聚物的分子量、分子量分布和分子结构,并用静态接触角仪和AFM分别表征聚合物膜的接触角、表面能及膜的表面形貌.

RAFT PREPARATION AND CHARACTERIZATION OF TRIFLUOROETHYL METHYLACRYLATE AND STYRENE COPOLYMERS

The copolymers of 2,2,2-trifluoroethyl methylacrylate(TFEMA) and styrene(St) were synthesized using reversible addition-fragmentation chain transfer(RAFT) polymerization in 1,4-dioxane solution,using S-1-dodecyl-S′-(α-methyl-α′-acetic acid)trithiocarbonate as the RAFT agent and 2,2′-azobisisobutyronitrile(AIBN) as initiator.The RAFT polymerization kinetics under different reaction conditions was discussed in detail.The molecular weight and chemical structure of P(TFEMA-co-St) were characterized by GPC and FTIR,respectively.The surface property and micro-topography of P(TFEMA-co-St) films were measured by contact angle method and AFM.The relatively suitable polymerization conditions were that the ratio value of TFEMA]/St]/RAFT]/AIBN]was 200∶200 ∶2∶1,and the polymerization temperature was 75℃.The results of copolymerization kinetics showed that the copolymerization was"living" and controllable.The activation energy of this polymerization was 36.49 kJ /mol.Plots of Mn versus conversion were linear.PDI of P(St-co-TFEMA) was between 1.2 and 1.4.FTIR and 1H-NMR results proved that P(TFEMA-co-St) were obtained,and that the copolymer chain showed a gradient-chain-structure character.The P(TFEMA-co-St) films had high water contact angles and relatively low surface energy,showing fluoropolymer’s characters.The micro-phase separation structure was observed in P(TFEMA-co-St) films.