FORMULATION AND POLYMERIZATION OF MICROEMULSIONS CONTAINING A MIXTURE OF CATIONIC AND ANIONIC MONOMERS

A series of polyampholytes of sodium-2-acrylamido-2-methylpropanesulfonate (NaAMPS) and 2-(methacryloyloxy) ethyltrimethylammonium chloride (MADQUAT) has been synthesized by free radical polymerization in microemulsions. The optimization of the formulation was, by a selection procedure, based on the hydrophile-lipophile balance (HLB) of the nonionic surfactants and solubility parameters of the different components. Both ionomers play an important role in the formulation owing to their amphiphilic and electrolyte characters as confirmed by surface tension and turbidimetry experiments. These effects control the HLB and interfacial properties of the microemulsions. The results are semi-quantitatively interpreted from the cohesive energy ratio (CER) concept. The reaction products are stable inverse latexes consisting of high molecular weight copolymers entrapped in water droplets particles and dispersed in an isoparaffinic oil.