Glass transition behavior of emulsion‐polymerized polymer films containing a surface‐active agent

摘要

AbstractThe glass transition behavior of emulsion‐polymerized poly(methyl methacrylate) and polystyrene films containing sodium laurylsulfate as emulsifier was studied by measurements of dynamic mechanical properties and thermal depolarization current. The film specimens of the emulsion‐polymerized polymers were prepared by casting from their benzene solutions. The glass transition temperatures of the emulsion‐polymerized films are higher than those of the bulk‐polymerized films. The higher glass transition temperature of the emulsion‐polymerized films is attributed to the colloidal properties of sodium laurylsulfate in the process of the film formation. The restriction of the molecular chains in the emulsion‐polymerized films is attributed to the interaction between the hydrophobic groups of sodium laurylsulfate and the polyme