聚甲基丙烯酸乙酯链结构核磁共振(NMR)研究

INVESTIGATION OF THE CHAIN STRUCTURE OF PEMA BY NMR

本文用~1H-NMR,^(13)C-NMR和化学位移相关谱(COSY)研究了聚甲基丙烯酸乙酯(PEMA)的链结构.虽然质子峰的重叠给谱的识别带来一些困难,但是利用H-H COSY和C-H COSY提供的信息讨论了PEMA的~1H谱和^(13)C谱中各谱峰的归属.归属β-CH_2的四元组立构序列仍有一些问题.最后计算了无规PEMA的五元组立构序列分布.

In this article the chain structure of PEMA was studied by 1H-NMR, 13C-NMR and COSY spectroscopy. Some difficulties in recognition of the spectra of PEMA come from the overlap of proton peaks. The assignment of the peaks in spectra of PEMA was discussed deeply with information provided from H-H COSY and C-H COSY spectra. But there are still some problems about the assignment of 13C peaks of β-CH2 in tetrad level. Finally the pentad sequences of atactic PEMA were calculated based on the discussion mentioned above.