ABSTRACT:Anionic cyclopolymerizabilities of N-methyldiacrylamide (MDA), N-propyldimethacrylamide (POMA), and N-methyldimethacrylamide (MOMA) were studied. MDA initiated by tert-butylmagnesium chloride at -78°C yields polymers which consists almost exclusively of 5-membered ring as repeating unit, even though the nature of solvents employed are varied widely. This indicates that MDA has strong tendency toward head-to-head and tail-to-tail additions even in anionic polymerization. NMR spectroscopic studies showed that conjugation between C=C and C=O double bonds of MDA is as effective as that of acrylic esters. Favorable conformation of MDA for the 5-membered ring formation and higher electron density of propagating anion (--CH2-CH--CO-) in spite of the fact that its acryloyl groups have conjugative nature are regarded as possible reasons for the unusual addition behavior. Attempted anionic polymerizations of POMA and MOMA were unsuccessful. NMR spectroscopic studies revealed that conjugation between olefin and C = 0 double bonds in these monomers is ineffective owing to the twisted conformation between the two double bonds. This unconjugative nature of the methacryloyl groups of POMA and MOMA is considered to be responsible for their lower polymerizability in the anionic polymerization.KEY WORDS

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