Molecular design of functional polymers having amino groups

Abstract

Three topics on molecular design of functional polymers having amino groups will be discussed. The first topic is on the synthesis of functional isoprene oligomers with one amino end group. The best condition for the synthesis is to seed a small amount of the amino-ended oligomer into a reaction system where isoprene was polymerized with lithium diisopropylamide as initiator. The highly active behavior of the amino-ended oligomer as chain transfer agent was ascribed to a “macromolecular effect”. The second topic is concerned with a study on the soluble poly(1,4-divinylbenzene) which was formed by polymerizing 1,4-divinylbenzene with lithium diisopropylamide in the presence of excess diisopropylamine in THF. Structural analyses with 400MHz1H NMR and 25 MHz13C NMR showed that there were 2 or 3 branchings per 100 monomeric units along the main chain. Population of the triad tacticities suggested the steric course of polymerization to proceed according to the Bernoulli statistics with respect to diad placements, m and r. Third topic is on a polyamine macromer which was prepared by allowing an ethylenediamine homologue, N,N′-diethylethylene-diamine (DEDA), to react with 1,4-divinylbenzene in the presence of lithium diisopropylamide as catalyst. Results on syntheses and properties of polystyrene-polyamine (SA) and poly(2-hydroxyethyl methacrylate)-polyamine (HA) graft copolymers will be presented with the emphasis on their biomedical behavior.