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1575592654

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[求助] 如何根据聚乙烯核磁氢谱计算其支化度已有1人参与

根据得到的氢谱结果，在0.51，0.91以及1.33处有明显的峰，所用试剂为氘代四氯乙烷，所以怎么根据这三个峰计算其支化度。

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上面文章的摘要：
ABSTRACT: The crystallinity of polyethylene, which significantly affects
the properties of the polymer, is quite sensitive to the concentration of its
branches. Thus, it is necessary to estimate branch concentration with
reasonable accuracy. Currently, 13C NMR and gel permeation chromatography−Fourier transform infrared spectroscopy are widely-used analysis
methods for the analysis of branch concentration. Despite several advantages,
these methods sometimes have limitations. For instance, the preparation of
samples for 13C- NMR is tedious because high-concentration samples are
required and the time for analysis is greater than 12 h. To more efficiently
estimate the branch concentration of polyethylene, we developed a new highfield 1
H NMR method with an improved peak resolution by employing (1)
homonuclear decoupling and (2) 2D heteronuclear correlation. The new
method was observed to significantly reduce the experimental time to ∼30
min; furthermore, sample preparation was relatively simple because the
method did not require high-concentration samples.