Kinetics of the thermal polymerization of styrene in stretched polytetrafluoroethylene films

Resumo

Polytetrafluoroethylene–polystyrene composite films are prepared by polymerizing styrene in a stretched polytetrafluoroethylene (PTFE) matrix immersed into a styrene monomer solution at 90°C. The kinetics of the thermal polymerization of styrene sorbed into the pores formed in the matrix is studied. A model of the polymerization process is proposed capable of describing the kinetics of polystyrene (PS) accumulation in the film, which, in particular suggests that the polymerization occurs in the bulk of growing PS inclusions at a constant concentration of monomer in them and that the formation of active sites most efficiently proceeds at their interface with the matrix. Stretched PTFE–PS composites containing up to 70 wt % PS in the matrix are prepared.