Application of a new pH-metric Method to the Kinetic study of copolymerization of polysaccharides Fucan N1 with PMMA in presence of Cerium Ce+4 .

Abstract

The copolymerization of a Poly-Acrylic PMMA with polysaccharide, Fucan N1 and Dextran T70,in presence of a ceric salt used as initiator in acidic medium ,was carried out under the following conditions : Fucan N1=0,5 g; []M.,CAN31063−= , []M2,0HNO3=; temperature =40°C with a relative ratio between the initiator and the monomer , initiator/monomer =1/10. Besides a pH study of the reaction medium , an infrared spectroscopy (IR) proved the appropriatness of these best conditions of synthesis , and this by showing the presence of a characteristic peak of the carbonyl grouping situated at 1733cm-1 for the copolymer Fucan PMMA in respect to the individual PMMA spectra and Fucan N1. In addition , a 13C NMR study has been conducted on the copolymer. A viscosimetry study of two Fucan fractions was performed in aqueous medium (H20), and also of the obtained copolymer in DMSO. An outcome of this work allows for us the suggestion of a plausible reaction mechanism , of which the copolymerization rate -Rp- is first order dependant to the monomer concentration, and to the square –concentration of both the initiator and the polysaccharide .