A novel methacrylate with a bisphosphonate group: RAFT polymerization and flame retardant property of the resultant polymers

A number of phosphorus-based monomers have been evaluated by free radical polymerization or photopolymerization, but fewer examples have been involved in the “living”/controlled radical polymerization (LRP) of such type of monomers, whereas LRP techniques allow the synthesis of well-defined polymers with designable structures, compositions and properties. In this work, a novel methacrylate based monomer with a bisphosphonate group 4-(bis(diethoxyphosphoryl)methyl)phenyl methacrylate (BPMA) was synthesized first and then polymerized by reversible addition-fragmentation chain transfer (RAFT) polymerization. The polymerization showed typical “living” features such as the polymerization, which indicates first order kinetics with respect to monomer concentration, and the molecular weights of the resultant polymers increase with monomer conversion. Furthermore, the resultant polymers demonstrated better thermal and flame-retardant properties. According to the thermal gravimetric analyzer (TGA) test, the amount of residual carbonaceous mass (char) increased with the molecular weight of the resultant polymers. Furthermore, the micro-scale combustion calorimetry (MCC) test also confirmed its superior flame-retardant performance.