Design of macromolecular topologies by electrostatic self-assembly and covalent fixation with telechelics having cyclic ammonium salt groups

Reactions of uniform-size telechelic polymers possessing moderately straine d 4- or 5-membered cyclic ammonium salt groups have been investigated in or der to exploit an efficient synthetic method for various macromolecular arc hitectures. In particular, telechelic poly (tetrahydrofuran)s having 5-memb ered cyclic ammonium (pyrrolidinium) salt groups were found to be attractiv e, since they were capable of forming the macromolecular assemblies through the Coulombic interaction with plurifunctional carboxylate counteranions a t ambient temperature, and their pre-organized structures can be permanentl y fixed through the ring-opening reaction by the nucleophilic attack of car boxylate anions at elevated temperatures. By making use of this unique feat ure of the cyclic ammonium salt groups, a series of branch and network poly (tetrahydrofuran)s has been synthesized, Furthermore, a new polymacromonom er architecture with mixed branch segments of different lengths has been co nstructed through reshuffling of poly (tetrahydrofuran) segments in an elec trostatic self assembly and subsequent covalent fixation process.