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Synthesis of Copolymers by Living Carbanionic Alternating Copolymerization
Author(s) -
Liu Kun,
Ren Lei,
He Qing,
Xu Wei Jian
Publication year - 2016
Publication title -
macromolecular rapid communications
Language(s) - English
Resource type - Journals
SCImago Journal Rank - 1.348
H-Index - 154
eISSN - 1521-3927
pISSN - 1022-1336
DOI - 10.1002/marc.201600009
Subject(s) - copolymer , carbanion , styrene , zwitterion , polymer chemistry , polymerization , materials science , chemistry , polymer , molecule , organic chemistry
The synthesis and characterization of copolymers from styrene and 1,3‐pentadiene (two isomers) are reported. Styrene/1,3‐pentadiene (1:1) copolymerization with carbanion initiator yield living, well‐defined, alternating ( r 1 = 0.037, r 2 = 0.056), and highly stereoregular copolymers with 90%–100% trans ‐1,4 units, designed M n s and low Ð M s (1.07–1.17). The first‐order kinetic resolution and NMR spectra demonstrate that the copolymers obtained possess strictly alternating structure containing both 1,4‐ and 4,1‐enchaiments. Also a series of copolymers with varying degrees of alternation are synthesized from para ‐alkyl substituted styrene derivatives and 1,3‐pentadiene. The degree of alternation is strongly dependent on the polarity of solvent, reaction temperature, type of trans ‐ cis isomer of 1,3‐pentadiene and para ‐substituted group in styrene. The macro zwitterion forms (SPC) through the distribution of electronic charges from the donor (1,3‐pentadiene) to the acceptor (styrenes) are proposed to interpret the carbanion alternating copolymerization mechanism. Owing to the versatility of the carbanion‐initiating reaction, the present alternating strategy based on 1,3‐pentadiene (especially cis isomer) can serve as a powerful tool for precise control of polymer chain microstructure, architecture, and functionalities in one‐pot polymerization.