Synthesis and characterization of sugar-based methacrylates and their random copolymers by ATRP
Abstract
Various sugar-based methacrylate monomers have been prepared and randomly copolymerized with methyl methacrylate (MMA) using classical atom transfer radical polymerization (ATRP). Firstly, four different sugar-based methacrylates are synthesized by two-step method: (i) etherification of protected monosaccharides with epichlorohydrin and (ii) following ring-opening reaction of obtained epoxides with methacrylic acid (MAA) in the presence of triethylamine. Next, these monomers are copolymerized with MMA via ATRP at 90 degrees C to obtain corresponding random copolymers. The molecular weights of the copolymers are determined by both GPC (gel permeation chromatography) and H-1-NMR (nuclear magnetic resonance spectroscopy) analyses and found as 10600 similar to 16800 and 12200 similar to 18500 g/mol, respectively. Moreover, the copolymer compositions are also determined by H-1-NMR analysis using characteristic signals of the monomers and found as about 94.1 similar to 97.8%, which are good agreement with feeding ratio. In addition, the glass transition temperatures of copolymers are found as 101.2 similar to 102.9 degrees C by changing type and composition of sugar-based methacrylate monomers. Overall, a series of well-defined random copolymers comprising different sugar-based methacrylates and methyl methacrylates were successfully synthesized by classical ATRP method.