Semicontinuous Heterophase Polymerization of Methyl and Hexyl Methacrylates to Produce Latexes with High Nanoparticles Content

Abstract

The semi-continuous heterophase polymerization (SHP) under monomer-starved conditions of methyl methacrylate and hexyl methacrylate is reported, at various monomer addition rates to elucidate the effect of monomer solubility on the mechanism of particle nucleation and growth. Polymer particles in the nanometer range from both monomers were obtained, which decreased in size as monomer addition rate was decreased. Molar masses of both polymers also diminished as monomer addition rate was slowed down. The propagation rate constant dictates how fast the starved condition is achieved rather than the monomer solubility in the aqueous phase. A slow particle rate of growth helps to obtain a narrower PSD.

Keywords:

• Free-radical heterophase polymerization
• monomer solubility
• particle size distribution
• nanotechnology

Acknowledgements

This research was supported by a grant from the Mexican Council of Science and Technology (CONACYT CB-2007-82437). Two of us (MGPG and AAM) thank CONACYT for scholarships to obtain their Ph.D. degrees.