Cationic ring-opening polymerization cyclic imino-ethers

The above listed monomers polymerize exclusively by cationic ring-opening polymerization. Polymerization of cyclic imino ethers has been reviewed by Saegusa1,4,). In this section we follow mostly the conclusions of the Kyoto group summarizing the applied synthetic methods. Subsequently we describe initiating systems, peculiarities of chain growth, side reactions, copolymerization systems and possible applications, in this order. [Pg.209]

Living cationic ring-opening polymerization (CROP) techniques represent important methods for the polymerization of a wide variety of heterocyclic monomers, such as cyclic ethers, cyclic amines, and cyclic imino ethers [7, 84-87]. The main differences between carbocationic polymerization of vinyl monomers and CROP of heterocyclic monomers arise from the nucleophilic heteroatoms... [Pg.172]

Cationic ring-opening polymerizations are also nucleophilic substitution reactions e.g. equation (7). Two experiments are frequently employed to follow the cationic polymerization of heterocyclic monomers. The first is based on the polymerization of a low molar ratio of monomer and initiator directly in an NMR sample tube. This experiment requires a low rate of polymerization and allows direct identification of all growing species and determination of the rate constants of all individual reaction steps by HNMR spectroscopy. Cyclic imino ethers were the first to be studied by this method. Subsequently, cationic polymerization of other heterocyclic monomers has been investigated." ... [Pg.1058]