Aliphatic cyclic carbonates and spiroorthocarbonates as monomers

In this review the synthesis and polymerization of aliphatic cyclic carbona tes of different size and type are presented. The mechanisms of cationic, a nionic, coordination and enzymatic polymerization of cyclic carbonates are discussed for obtaining polymers with well-defined structures and oligomers with reactive pendant and end groups. The reactions of cyclic carbonates w ith different nucleophilic reagents leading to products with CO2 retention or with decarboxylation are reported. Special attention has been paid to th e synthesis and polymerization of spiroorthocarbonates, bicyclic acetals, w hich are the intermediates in the reaction of cyclic carbonates with cyclic ethers. The influence of the presence of neighboring groups such as methyl ene or epoxy groups on the polymerization mechanism of spiroorthocarbonates , as well as the volume expansion during polymerization is discussed. As a result of the above synthetic findings, a variety of novel materials have b een developed with versatile applications in different fields such as biome dicine and electronics. (C) 2000 Elsevier Science Ltd. All rights reserved.