Dispersion polymerization of methyl methacrylate in supercritical carbon dioxide using vinyl terminated poly(dimethylsiloxane)

PMMA has applications on the medical, pharmaceutical and engineering areas. Different processes may be employed for its production. Here, MMA polymerization was performed by supercritical carbon dioxide dispersion. CO2 is inert, easily retrievable and separated from the product. The monomer is soluble in dense CO2, unlike PMMA, requiring a stabilizer to maintain the dispersion. Here, vinyl terminated PDMS was used as a dispersing agent. The reactions were conducted at 16 MPa/80 degrees C for 4 h. Product characterization was performed by SEM, to evaluate the morphology at estimate the particle size, SEC, to determine the molar mass and polydispersion index, H-1 NMR and FTIR spectroscopy, in order to verify the chemical structure of the product, and also gravimetric analyses, to determine the residual monomer. The results confirmed the adequacy of the process and of the stabilizer for PMMA particles production. (C) 2015 Elsevier B.V. All rights reserved.