Synthesis and characterization of emulsion polymers using isopropenyl acetate

Abstract

Background: Isopropenyl acetate (IPA) is one of the monomers from acetate family having an unsaturation with a methyl group attached to the ethylenic carbon. The unsaturation present in the monomer can be utilized for free radical polymerization. Irrespective of this, IPA is not studied much in emulsion polymer synthesis. In the current study, we report the preparation of emulsion polymers using IPA and other acrylic monomers. Terpolymers of butyl acrylate (BA), methyl methacrylate, and IPA were prepared via seeded emulsion polymerization with varying IPA proportions on molar basis. Potassium persulfate was employed as an initiator along with Dowfax 2A1 as surfactant (anionic). Results: The emulsions prepared thereof were characterized for particle size, zeta potential and molecular weight using gel permeation chromatography. The emulsion films were evaluated using Fourier transform infrared spectroscopy, as well as their thermal (differential scanning calorimetry, thermo gravimetric analysis) and mechanical properties to study the effect of isopropenyl acetate on their overall properties. Conclusions: With increasing proportion of IPA in the formulation, lower conversion was observed which could be due to the lower reactivity of IPA for radical polymerization in the presence of these comonomers. More study for the utilization of IPA in polymer synthesis is needed which, on successful optimization, would give a cost-effective alternative to various commercial acrylic monomers.