摘要：

Three samples of poly(1,2-cyclohexene oxide) were prepared with ZnEt2, (EtZnOMe)4, and [{MeOCH2CH(Me)OZnO(Me)CHCH2OMe}2 · {EtZnO(Me)CHCH2OMe}2] ([Zn-MP]2,2), respectively, as initiator. Each polymer sample was treated with butyllithium to form various decomposition products having double bonds or hydroxyl groups as end groups. Two dimeric diols, were obtained from the decomposition products and were found to have isotactic (SSSS or RRRR) and syndiotactic (RRSS) structure, respectively. By comparison of the relative yield of the two dimeric diols from each sample with the relative intensity of the three major signals in their 1H NMR spectra, the latter were assigned to methine protons of isotactic, syndiotactic, and heterotactic triads (from downfield to upfield). It was found that most parts of the main chain of the polymer prepared with [Zn-MP]2,2 were composed of syndiotactic triads, SSRRSS (or RRSSRR), while the polymer prepared with ZnEt2 or (EtZnOMe)4 contained syndiotactic and heterotactic triads in comparable amounts.

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