Frontal Polymerization of Deep Eutectic Solvents Composed of Acrylic and Methacrylic Acids

Frontal polymerization of deep eutectic solvents (DESs) made with acrylic or methacrylic acid as the monomer and hydrogen bond donor was studied. Fronts with acrylic acid and choline chloride propagated more uniformly than with pure acrylic acid, so an exploration into how the DES affected frontal polymerization was performed. The hydrogen bond acceptor of the DES was replaced by several analogs to determine the effect on the DES front behavior. The analogs used were talc, DMSO, lauric acid, and stearic acid, which acted as a heat sink, inert diluent, hydrogen bonding diluent, and inert phase change material, respectively. None of the methacrylic acid-analog systems were able to sustain a front. While the acrylic acid-analog systems did sustain a front (with the exception of stearic acid), none of the fronts replicated the acrylic acid DES behavior. The acrylic acid-talc sample behaved more violentlylike pure acrylic acid polymerizationthan the acrylic acid DES, and the DMSO and lauric acid samples produced slower fronts than that of the acrylic acid DES. We propose that the reactivity of the acrylic acid and methacrylic acid is enhanced in the DES. (c) 2017 Wiley Periodicals, Inc. J. Polym. Sci., Part A: Polym. Chem. 2017, 55, 4046-4050