THE INVERSE EMULSION POLYMERIZATION OF ACRYLAMIDE WITH PENTAERYTHRITOLMYRISTATE AS EMULSIFIER - 1 - EXPERIMENTAL STUDIES

The inverse emulsion polymerization of aqueous acrylamide solutions in isooctane as dispersing media with the emulsifier pentaerythritolmyri state and an oil-soluble azo initiator was studied, particularly with respect to the influence of the chemically pure emulsifier. In this fr ee radical polymerization, a water-in-oil emulsion with droplet sizes around 10 mu m is converted into a latex with average particle diamete rs between 80 and 200 nm containing a polymer with molar masses up to 16 x 10(6) gmol(-1) Kinetic data were measured by adiabatic as well as by isothermal calorimetry. The influences of various parameters on po lymerization kinetics, particle numbers and molar mass averages were s tudied. Experimental results show a positive influence of the emulsifi er concentration on the reaction rate and indicate the dominance of a bimolecular termination reaction with respect to the polymer radicals above a certain initiator concentration. (C) 1998 SCI.