The optical properties of chiral centers used as tools for studying irreversible or reversible reactions of synthetic polymers in solution

The optically active manifestations (ORD and CD) of asymmetric centers of synthetic macromolecules are discussed. Well known for conformational studies, they can also detect or give quantative information about the covalent or associative reactions of these polymers when important contributions of rigid or ordered structures are absent. The Moffitt equation can not only characterize the helical conformation of polypeptides but it is also, and in a more general manner, satisfied when at least one of the Cotton effects of sufficient amplitude contributing to the ORD of the polymer is of opposite sign to the other ones. These contributions are met in several cases which are classified and illustrated. An example is given where the b0 constant of the Moffitt equation is used to determine the composition of a copolymer resulting from a chemical modification of some of the monomeric units of a polymer. The results are discussed.