| Vinyl chloride-isobutyl vinyl ether (VC-IBVE) exhibits good chemical resistance, weather resistance and adhesive strength with metals, so it is one of useful base resins for coating and ink. This paper was devoted to the preparation of VC-IBVE copolymers by emulsion copolymerization. Influences of polymerization recipe and conditions on the polymerization kinetics, molecular weight and copolymer composition, and relationship between structure and properties of copolymers, were investigated. The results would provide base for producing of VC-IBVE copolymer in industrial scale.VC-IBVE copolymer was synthesized by emulsion copolymerization, using (NH4)2S2O8/Na2SO3/CuSO4 as the initiator system and sodium dodecyl sulfonate (SDS) as the emulsifier. Influences of feeding monomer composition, polymerization temperature, concentrations of initiator system and SDS, and feeding policy on polymerization kinetics were investigated. VC-IBVE emulsion copolyization could be carried out in relatively lower temperature by using ternary redox initiator system. The polymerization rate (Rp) increased as concentration of initiator and polymerization temperature increased. Rp decreased as the molar fraction of IBVE in feeding monomers increased. Rp tended to be uniform when VC was added steply. SDS concentration had no obvious influences of Rp, but the stability of the resulting emulsion was lower when SDS concentation was lower. The instrinc viscosity of VC-IBVE copolymer decreased as IBVE molar fraction in feeding monomer and polymerization temperature increased, while it changed no more as the concentrations of initiator and SDS varied.VC-IBVE copolymers with relatively uniform composition distribution and good solubility in toluene were prepared by controlling the conversion in batch emulsion copolymerization and adding of VC steply in semi-batch emulsion copolymerization. By modifying the reacting monomer compostion or reactivity ratio, the copolymercompostion~conversion relationship obtained by using copolymerization composition equation fitted well with experimental results.IBVE mainly existed in single unit in VC-IBVE copolymer and the methylene group of VC mainly bonded with methylidyne group of IBVE. The solubility of VC-IBVE copolymer inreased as VC molar fraction in copolymer increased, and VC-IBVE copolymer could be soluble in toluene when VC molar fraction was lower than 0.95. The glass temperature of copolymer decreased as IBVE fraction increased. Copolymers prepared by semi-batch emulsion copolymerization had narrower glass transition than copolymer prepared by batch copolymerization.
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