INVERSE MICROEMULSION POLYMERIZATION OF ACRYLAMIDE IN THE PRESENCE OFA MIXTURE OF OLEOPHILIC HYDROPHILIC SURFACTANTS/

The effect of sodium dodecyl sulphate (SDS) on the formation of invers e micro-emulsion toluene/sodium bis(2-ethylhexyl)sulphosuccinate (AOT) /water/acrylamide (AAm)/SDS and on polymerization of acrylamide initia ted by oil soluble dibenzoyl peroxide was studied. The presence of SDS shifts the value of the volume fraction of aqueous phase (Phi(aw)) at which a two-phase Winsor II system forms, to higher values. It was sh own that an increase of the mass ratio of SDS/water led to a decrease of acrylamide polymerization rate, of polyacrylamide particle size and of polyacrylamide molecular mass distribution. It was also found that in the presence of SDS, a nearly constant value for acrylamide polyme rization rate in inverse micro-emulsion in the range of Phi(aw) values between 5% and 50% can be obtained. The polymerization kinetics and p olymer particle formation were explained as consequences of the initia tion of acrylamide polymerization in two reaction loci-in inverse mice lles and in the oil macrophase of the inverse micro-emulsion. (C) 1998 SCI.