STUDIES OF REACTIVITY RATIOS IN CO POLYMERS

Abstract

Synthetic/polymeric materials have become the most useful commodities of the modern world , in the form ofelastomers, plastics & fibers. In recent years the emphasis in research and production of synthetic macromolecules has been directed toward preparation of cost-effective multi components polymer systems like copolymers. For prediction of copolymers behaviour several models have been proposed by authors like simple end termination model and penultimate model and experience has shown that the former is applicable for the most of the copolymer systems.To apply this modelfor predicting the properties of the copolymers, two constant parameters R1 and R2 called reactivity ratio of monomer 1 and 2 are calculated. However several methods for finding these parametersare are available in the literature but most of them have not enough accuracy in predicting the values of these parameters , therefore, the major purpose of the present work was to develop a new method for finding out the values of reactivity ratios of monomers and comparing them with the reported values calculated by the other methods in the same conditions. In an attempt to.prove the validity of the methods used for the calculation of the reactivity ratios, author has taken experimental data for eighteen copolymer systems from the literature and used them in all ten methods to calculate the values of the reactivity ratios. Author arrived at a conclusion that method no.5 and 7 are able to provide better results in most of the chosen systems in comparison to seven other methods but application of tenth method which has been derived by author, was found to be the best one. All of attempts would be done by computer aid.