Macromolecules, Vol.38, No.16, 6939-6945, 2005
Emulsion polymerization of novel transparent latices by pulsed electron beam initiation
The use of electron irradiation as an alternative to chemical initiation in emulsion polymerization is a well-known but not widely used technique. The pulsed electron beam polymerization (PEBP) allows the synthesis of unique latices with small particle sizes at low surfactant concentrations. PEBP of methyl methaerylate (MMA), ethyl methacrylate (EMA), butyl methacrylate (BMA), vinyl acetate (VAO, and styrene (Sty) was performed with regard to the production of transparent latices at low surfactant concentrations. The development of novel polymers with the focus on bio- and nanornaterials is intensely investigated nowadays, and the developed latices might find an application in this area. The reason for the formation of small sized latex particles was identified in the high radical flux applied to the system by the high-frequency pulsed electron beam (PEB) resulting in a high degree of low molecular weight polymeric material. The presence of hydroxy-functionalized polymer chains seems to colloidally stabilize small latex particles and prevent coagulation even at low surfactant concentrations. A high k(p) in combination with a good water solubility of the monomer enhanced the possibility for the formation of transparent latices by PEBP.