Hyperbranched polymers made from A(2), B-2 and BB '(2) type monomers, 2. Preparation of hyperbranched copoly(sulfone-amine)s by polyaddition of N-ethylethylenediamine and piperazine to divinylsulfone

The new approach for preparation of hyperbranched polymers from commerciall y available A(2) and BB'(2) type monomers was further extended to synthesiz e hyperbranched copolymers. In this work, hyperbranched copoly(sulfone-amin e)s were prepared by polyaddition of piperazine (B-2) and N-ethylethylenedi amine (BB'(2)) to divinylsulfone (A(2)) The polymerization mechanism was in vestigated with FTIR and LC-MSD. During the copolymerization, secondary-ami no groups of piperazine and N-ethylethylenediamine react rapidly with vinyl groups of divinylsulfone within 50 s, and then the residual vinyl groups r eact with primary-amino groups resulting in hyperbranched copoly(sulfone-am ine)s. The crystallization behaviors of the resulting polymers were charact erized with DSC and X-ray diffraction. When the initial mole ratio of B-2 t o BB'(2) is equal to or higher than three, r greater than or equal to 3, re sulting copolymers are semi-crystalline, while those with r < 3 are amorpho us. Interestingly, the resulting polymers with r = 3 exhibit the highest me lting temperature comparing with other semi-crystalline samples. The degree of branching of hyperbranched copolymers was determined by H-1 NMR. (C) 20 01 Elsevier Science Ltd. All rights reserved.