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Conformational Transition between Random Coil and Helix of Copolymers of N-Propargylamides

✍ Scribed by Jianping Deng; Junichi Tabei; Masashi Shiotsuki; Fumio Sanda; Toshio Masuda

Publisher
John Wiley and Sons
Year
2004
Tongue
English
Weight
162 KB
Volume
205
Category
Article
ISSN
1022-1352

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✦ Synopsis

Abstract

Summary: Copolymerization of two N‐propargylamides bearing pendent groups with different lengths [monomer 4, HCCCH~2~NHCO(CH~2~)~4~H; monomer 8, HCCCH~2~NHCO(CH~2~)~8~H] was carried out and the conformational transition behavior of copolymers with different compositions was examined systematically. The copolymers could form relatively stable helices even though both of the corresponding homopolymers, poly(4) and poly(8), could not take a stable helical conformation under the same conditions. The helix content of copolymers reached a maximum when the content of monomer 8 was 61%. These results are explained in terms of the idea that the copolymers have higher cis‐content and that the intramolecular hydrogen bonding is more effective in these copolymers compared with the corresponding homopolymers.

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