关键词:

TiO₂, 含甲基丙烯酸共聚物, 复合粒子, 乳液聚合, 动力学

Abstract:

The TiO₂/methyl-methacrylate-butyl acrylate-methacrylic acid copolymer ［TiO₂/P(MMA-BA-MAA)］composite particles were synthesized by emulsion polymerization.The emulsifier concentration and molar concentration ratios of monomers exhibited a great influence on the morphology of the composite particles.The effects of operation variables, such as emulsifier concentration, initiator concentration, molar concentration ratios of monomers, co-emulsifier concentration, polymerization temperature on the kinetic features were also investigatedThe TEM images, FTIR spectra and TG analysis indicated that the composite particles of TiO₂/P(MMA-BA-MAA) with smooth surface, good dispersibility and spherical core-shell structure were obtained.The kinetics data showed that under the conditions studied the rate equation for the whole reaction of coating polymerization was educed,and the apparent activation energy was 163.0 kJ.mol^-1, which suggested that the possible reaction mechanism could be “TiO₂/surfactant” micelle nucleation and homogeneous coagulative nucleation mechanism of the emulsion polymerization of MMA-BA-MAA.Thermal analysis showed that the thermal stability of composite particles was higher than that of copolymer particles formed under the same conditions.Compared with nano-TiO₂, the measurements of ζ-potential and contact angles of composite particles indicated that the hydrophilicity of composite particles decreased and the hydrophobicity increased.

Key words:

TiO₂, 含甲基丙烯酸共聚物, 复合粒子, 乳液聚合, 动力学