Journal of Polymer Science Part A: Polymer Chemistry, Vol.39, No.16, 2813-2820, 2001
Emulsion polymerization of methyl methacrylate in the presence of novel addition-fragmentation chain-transfer reactive surfactant (transurf)
Reactive surfactants allow the surfactant molecules to become covalently bound to the particles and thus provide added stability to the colloid particles, longer shelf life, better shear resistance, and polymer particles that can be redispersed. This article reports for the first time the use of a novel addition-fragmentation chain-transfer reactive surfactant (transurf) in ab initio emulsion polymerizations of methyl methacrylate at 70 degreesC. It was found that the rate was lowered and average particle diameter nearly doubled when the transurf was used as compared with the SDS experiments (control). In addition the molecular weight distribution was very broad but had a lower Mn than observed in the sodium dodecyl sulfate experiment. Unfortunately because of the formation of many water-soluble oligomers, the amount of transurf incorporated could not be obtained accurately. However, it was estimated theoretically that only a very small amount of transurf would be consumed, but for an alternative method to increase the incorporation of transurf into the particles, the ratio of monomer to transurf must be kept as low as possible. The best way to achieve this would be to carry the experiments out under starved-feed conditions.