Amphoteric initiators suitable for emulsifier-free emulsion polymerization and the properties of the resulting latices

S. J. Fang, K. Fujimoto, S. Kondo, K. Shiraki, H. Kawaguchi

研究成果: Article査読

11 被引用数 (Scopus)

抄録

The soap-free emulsion polymerizations of styrene (St) and acrylamide (AAm) or methyl methacrylate (MMA) were carried out in the presence of three kinds of amphoteric initiators, and the polymerization kinetics and the colloidal properties of the latices produced were emphatically investigated. It was found that the number of carbon atoms between the amidino and carboxyl groups in each initiator exhibited an appreciable effect on the dissociation as well as on the solubility of the initiator in water, and therefore, that the properties of the colloidal particles depended on the structure of the initiators used. All the copolymerization runs, except for the polymerization using (2,2′-azobis(N-(2-caboxyethyl)-2-methylpropionamidine) under a strongly alkali condition, gave amphoteric latices, which indicated higher critical flocculation concentrations at lower or higher pHs than at a medium pH. The surface charge density measured by titration for poly(St/MMA) particles was about 3-10 times as high as that for the poly(St/AAm) ones, though these were prepared under the same conditions other than the monomer composition. The influence of the polymerization pH on both the polymerization rate and the surface charge density of the resulting latices was negligible even if the constants of the decomposition rate and the dissociation of the amphoteric initiators strongly depended on the pH of the medium.

本文言語English
ページ(範囲)589-596
ページ数8
ジャーナルColloid and Polymer Science
279
6
DOI
出版ステータスPublished - 2001 1月 1

ASJC Scopus subject areas

  • 物理化学および理論化学
  • ポリマーおよびプラスチック
  • コロイド化学および表面化学
  • 材料化学

フィンガープリント

「Amphoteric initiators suitable for emulsifier-free emulsion polymerization and the properties of the resulting latices」の研究トピックを掘り下げます。これらがまとまってユニークなフィンガープリントを構成します。

引用スタイル