Cyclopolymerization. V. Monomer design for the synthesis of highly cyclized polymer from unsymmetrical unconjugated dienes: Synthesis and polymerization of N‐methyl‐N‐allylmethacrylamide

Abstract N‐Methyl‐N‐allylmethacrylamide (MAMA) was synthesized and polymerized with radical initiators, and the structure of poly‐MAMA was studied, in order to establish the concept that difunctional monomers having monofunctional counterparts which do not polymerize are likely to give rise to highly cyclized polymer, if the cyclized polymer is in a lower free‐energy level than the monomer. The cyclopolymerizability of MAMA was considerably higher than that of N‐allylmethacrylamide, which was previously reported, and its monofunctional counterpart can be polymerized. The extent of cyclization of poly‐MAMA was about 93%, even in the polymer obtained by bulk polymerization. The repeating units of poly‐MAMA consist mainly of five‐membered rings; six‐membered rings and pendent methacryl groups were detected in addition as minor repeating components. The monofunctional counterparts of MAMA, i.e., N‐methyl‐N‐n‐propylmethacrylamide (MPMA) and N‐methyl‐N‐allylisobutyramide (MAIA), were also synthesized. Neither MPMA nor MAIA showed any tendency toward polymerization under the same experimental conditions as used for MAMA. The results thus obtained all support the concept mentioned above.