NONIONIC SURFACTANT EFFECTS ON POLYMER DIFFUSION IN POLY(BUTYL METHACRYLATE) LATEX FILMS

The influence of non-ionic surfactant molecules on polymer interdiffus ion in poly(butyl methacrylate) (PBMA) latex films was investigated us ing the non-radiative energy transfer technique. It was found that non ylphenoxypoly(ethylene oxide) surfactants such as NP-20 and NP-100 act as plasticizers to enhance the polymer diffusion rate. The increase i n diffusion rate with the increase in surfactant concentration is in c omplete accord with the Fujita-Doolittle free volume model. This sugge sts that by the time the latex dispersion is dry, the surfactant has d iffused uniformly into the latex polymer.