Effect of different parameters in emulsion copolymerization of vinyl chloride/vinyl acetate

Emulsion copolymerization of vinyl chloride with vinyl acetate comonomer was performed. Different conditions of initiators, emulsifier, and comonomer concentration were chosen in order to investigate the copolymerization reaction. Potassium per-sulphate, a mixture of stearyl alcohol and sodium lauryl sulphate (SLS) were used and reactions were performed at 55 degrees C in a pressurized reactor. Two region of pressure change were distinguished in the pressure-time curves in which by increasing the initiator concentration the flat region was shortened and the descending region showed a higher slope indicating higher reaction rate. Higher initial pressure was found in higher emulsifier concentration while higher pressure drop was achieved in the second region of pressure-time curves. Effect of comonomer content on heat release during copolymerization was studied. Conversion and intrinsic viscosity of the copolymers and their correlation with reaction parameters were also investigated.