| In the presence of β-cyclodextrin (β-CD), reversible addition-fragmentation chain transfer (RAFT) polymerization technique has been successfully applied to controlmolecular weight and polydispersity (M|—_w)/(M|—_n) in miniemulsion polymerization of butylmethacrylate, using 2-cyanoprop-2-yl dithiobenzoate (CPDB) as chain transfer agent (CTA or RAFT agent) and 2,2'-azoisobutyronitrile (AIBN) as initiator. β-Cyclodextrin acted as both a stabilizer and a solubilizer to assist the transportation of the water-insoluble, small-molecular-weight RAFT agent into polymerization loca (i.e. droplets or latex particles), so to ensure the RAFT agent to be homogeneous in polymerization loca. The polymers produced in the system of β-CD exhibited narrower polydispersity(1.2<(M|—_w)/(M|—_n)<1.3) than that of the case without β-CD. Moreover, the molecular weight(M|—_n) in the former case could be controlled by a definite amount of the RAFT agent.Significantly, β-cyclodextrin has been proved as a favorable effect on the stability of polymer latex, and no coagulum was observed. The effects of concentrations of the RAFT agent and AIBN on the conversion, the molecular weight and its distribution, as well as the particle size of latexes have been investigated in detail. Furthermore, the influences of the variations of surfactant (sodium dodecyl sulfate, SDS) and co-stabilizer (hexadecane, HD) on the RAFT/miniemulsion polymerization were also studied.On the base of upwards studies, the block copolymerizations of butyl methacrylate and fluorinated monomer(2, 2, 2-trifluoroethyl methacrylate(TFEMA) and 2, 2, 3, 4, 4.4-hexafluorobutyl methacrylate(HFBMA)) were investigated. The influences of the macro-CTAs synthesized by different polymerization techniques on the block copolymerizations were studied, too. Their structures were confirmed by FT-IR> 1~H NMR and (19)~F NMR. Their molecular weights and molecular weight distributions were analyzed by GPC.
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