ABSTRACT
Copolymerization allows various monomers to be combined in such a way so as to provide materials with useful and sometimes unique properties. Linear polyethylene and isotactic polypropylene homopolymers are both semi-crystalline plastic materials, but a random copolymer of the two, in the appropriate proportions, is an elastomer. Both the Mayo-Lewis and Fineman-Ross methods depend upon use of the instantaneous copolymer equation and as such are subject to various errors. Monomers with very bulky groups could clearly have trouble polymerizing. If the monomer has a structure that allows a radical site to be resonance stabilized, then in general there is a decrease in the reactivity of this monomer, relative to one where there is no resonance stabilization. The advent of spectroscopic methods, particularly nuclear magnetic resonance (nmr) spectroscopy, not only facilitated the determination of overall copolymer composition, but allowed the measurement of sequence distributions.
