Synthesis and polymerization of styrene monomer carrying isothiocyanate moiety and its copolymerization with HEMA based on chemo-selectivity to nucleophiles

Abstract

Isothiocyanate is a very useful functional group for post-polymerization modification by the reaction with amine or alcohol. An isothiocyanate monomer, 4-vinylbenzyl isothiocyanate, was synthesized from 4-vinylbenzyl chloride without using any harmful reagents such as thiophosgene and CS2. The obtained monomer was successively polymerized by the conventional radical polymerization (AIBN, 1,4-dioxane, 60 °C) to afford the corresponding polymer. The obtained polymer was characterized by 1H NMR, FTIR, thermogravimetric analysis (TGA), and differential scanning calorimetry. In contrast to the isocyanate group, the isothiocyanate group was relatively tolerant to alcohols, and this character enabled us to synthesize a copolymer of 4-vinyl benzylisothiocyanate and (2-hydroxyethyl methacrylate). The copolymer is transformed into networked polymer by 1,8-diazabicyclo[5.4.0]undec-7-ene as a promoter of the reaction between isothiocyanate and alcohol to afford thiocarbamate. The formation of networked polymer was characterized by FTIR and TGA. © 2013 Wiley Periodicals, Inc. J. Polym. Sci., Part A: Polym. Chem. 2013, 51, 5215–5220