Self-Emulsion Polymerization of Alkyl Alpha-Hydroxymethyl Acrylate:
Amphiphilic alkyl α-hydroxymethyl acrylates can be polymerized via self-emulsion polymerization (i.e., without surfactants) under conventional radical and reversible addition-fragmentation chain transfer polymerization conditions. The α-hydroxymethyl acrylates can be copolymerized at very low percentages (∼5%) with conventional monomers such as butyl acrylate under surfactant free conditions. The hydroxyl group of the α-hydroxymethyl acrylates in the resultant latex could potentially be used for further functionalization or for modulation of surface properties.
Densely functionalized polymers based on the Baylis-Hillman reaction:
The Joy Lab is keenly interested in developing polymers with dense functionality, for various biological and engineering applications. In line with this aim, we have utilized the Baylis-Hillman reaction for the development of densely functionalized polymers. The Baylis-Hillman reaction, which is a carbon-carbon bond forming reaction between an aldehyde and an activated alkene, was utilized to prepare densely functionalized monomers suitable for chain and step polymerization. By reacting formaldehyde with various alkyl acrylates, a series of alkyl a-hydroxymethyl acrylate monomers were synthesized. These monomers efficiently underwent RAFT polymerization to provide a-hydroxymethyl substituted polyacrylates with well controlled molecular weight and low polydispersity. The resulting homopolymers were also efficient macro-chain transfer agents for further RAFT polymerization. The Baylis-Hillman reaction was also utilized to synthesize alkene functionalized diols which underwent step-growth polymerization to provide polyesters and poly(ester urethane)s. Furthermore it was demonstrated that the alkene group can be quantitatively functionalized by thiol-ene click chemistry to provide a series of polymers with diverse physical properties.
|Nanoparticles formed from such Baylis-Hillman based polyacrylates. The amphiphilic nature of the polymers enable preparation of such nanoparticles without any surfactants|