RAFT Copolymerizationof Glycerol-Derived Vinyl EthersPossessing Acetal-Protected Diols for Biobased Hydrophilic and ThermoresponsivePolymers

Here, we synthesized a vinyl ether with acetal-protected diols from glycerol and acetone. The glycerol-derived vinyl ether was copolymerized with common vinyl monomers, methyl acrylate (MA) and <i>N</i>-isopropylacrylamide (NIPAM), via the reversible addition–fragmentation chain transfer (RAFT) mechanism. Through the monomer reactivity ratio analysis, relatively high copolymerization reactivity was observed with MA, while for NIPAM copolymerization, the reactivity ratio changed slightly depending on the polymerization solvent. The acetal deprotection reaction following the copolymerization proceeded nearly quantitatively, yielding well-defined copolymers with glycerol-derived diol groups. For the NIPAM copolymers, the thermoresponsive behavior was investigated before and after deprotection, resulting in tunable cloud points ranging from 20 to 46 °C by incorporating just 10% of glycerol-derived monomers into poly(NIPAM).