SURFACE FUNCTIONALIZATION OF POLYSTYRENE LATEX-PARTICLES WITH A LIPOSACCHARIDE MONOMER

Emulsifier-free latexes with immobilized carbohydrate residues have been prepared by batch or seed (co)polymerization of styrene in the presence of 11-(N-p-vinylbenzyl)amido undecanoyl maltobionamide (LIMA). The critical micelle concentration and the molecular surface area of LIMA were determined by surface tension and fluorescence measurements. Batch polymerization of LIMA with styrene was first performed using potassium persulfate, proving the efficiency of LIMA as emulsifier. Seed copolymerization was then investigated using polystyrene seed particles with varying experimental conditions (especially the LIMA surface coverage). Material balance of LIMA between aqueous phase and particles was obtained by separating both phases by ultracentrifugation and it was found that the surface-active monomer is preferentially on or in the particle (nearly 100% in batch and at most 70% in seed copolymerization). The presence of the carbohydrate residues at the particle surface was directly evidenced by H-1-nuclear magnetic resonance, electron spectroscopy for chemical analysis and electrophoretic mobility.