| Acrylate polymers are widely used because of their superior performance. The acrylate coating exhibits good chemical resistance, weather resistance, light maintenance, color maintenance. And the resin for medical use exhibits good water resistance, transparence, adhesive strength and low toxicity. This thesis was devoted to the preparation of methyl methacrylate/ethyl acrylate (MMA/EA) copolymers for coating application by bulk polymerization and that for medicine application by emulsion polymerization. Influences of polymerization recipe and conditions on the polymerization kinetics, molecular weight, size and size distribution of copolymer latex particles, were investigated.Influences of concentrations of initiator and chain transfer agents, polymerization temperature and feeding monomer composition on bulk polymerization kinetics were investigated. The polymerization rate (Rp) increased as concentration of initiator benzoyl peroxide (BPO) and polymerization temperature increased. Rp and the gel effect decreased as concentration of mercaptoethanol (ME) increased, which resulted from the redox reaction between ME and initiator. Rp decreased at first and then increased as the MMA molar fraction in feeding monomer increased. The molecular weight of MMA/EA copolymer decreased as concentrations of initiator, chain transfer agents and polymerization temperature increased. The molecular weight distribution increased as concentration of chain transfer agents increased. The molecular weight of MMA/EA copolymer decreased at first and then increased as MMA molar fraction in feeding monomer increased.Tg of MMA/EA copolymer increased as the MMA molar fraction in feeding monomer increased. Tg obtained by using the revised Barton & Johnson equation fitted well with experimental results. MMA/EA bulk copolymerization was carried out at following conditions: molar fraction of MMA:EA was 65:35, concentrations of BPO 0.15wt%, concentrations of ME 0.25-0.30wt% to total monomer weight, polymerization temperature 85 ℃. And the MMA/EA copolymer gained had Tg of63 ℃ and Mw of about 140000, which were expected for the coating application.Influence of concentrations of initiator, emulsifier, polymerization temperature and feeding monomer composition on the kinetics of MMA/EA emulsion copolymerization, were investigated. The initial polymerization rate (Rp) was proportional to the 0.78 power of the concentration of initiator (KPS). Rp increased as the concentration of emulsifier (OP) increased. The number of particles per volume unit increased as the concentrations of initiator and emulsifier increased. The average number of radicals per particle was higher than the theoretic value 0.5 as the concentrations of initiator and emulsifier varied and it decreased as the concentration of emulsifier increased. Rp increased as polymerization temperature increased. Rp decreased at the first stage and then increased as the MMA molar fraction in feeding monomer increased. The molecular weight of MMA/EA copolymer decreased as concentration of initiator and polymerization temperature increased. The number-average molecular weight was proportional to the -0.68 power of the concentration of initiator. The molecular weight of MMA/EA copolymer increased as concentration of emulsifier increased.The mean size of latex particles decreased as the concentrations of initiator and emulsifier increased, and increased as the polymerization temperature increased. The distribution of particle size increased as the concentration of initiator and polymerization temperature increased, and decreased as the concentration of emulsifier increased. The coagulation ratio decreased as the concentration of emulsifier increased and increased as polymerization temperature increased.
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