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用溶液高分辨￣（１３）ＣＮＭＲ谱首次研究了由二苯甲酮（ＢＰ）光引发低密度聚乙烯模型化合物直链烷烃ｎ－Ｃ＿（２４）Ｈ＿（５０）交联所产生的Ｈ型交联点的结构特征．现已检测和鉴定了光交联样品中与Ｈ型交联点相联系的－ＣＨ，α－ＣＨ＿２和β－ＣＨ＿２上碳的共振谱线，其数据与Ｈ型交联点模型化合物、γ－辐射交联正烷烃和聚乙烯所得到的结果符合得很好．在４０．８３ｐｐｍ处出现的一个新峰可指认为Ｈ型文联点的次甲碳，其相应的３１．５７和２８．３７ｐｐｍ处的另外两个新峰分别指认为相邻的α－ＣＨ＿２和β－ＣＨ＿２上碳的共振．本工作中的定量研究表明：在真空和熔融态条件下莱外光照３－５ｍｉｎ的样品中Ｈ型交联点的数目据估计为每１００００个碳原子８．５～１１．０个．
The H-type interaction of n-C_ (24) H_ (50) cross-linked linear paraffins from benzophenone (BP) photoinitiated LDPE model compounds was first studied by high resolution 13CNMR spectroscopy The structural characteristics of the joint. The resonance spectra of carbon on -CH, α-CH_2 and β-CH_2 linked to H-type crosslinking sites in the photocrosslinked samples have been detected and identified. The data are consistent with the H-type crosslinking compounds, γ- The results obtained by radiation crosslinking n-alkanes and polyethylenes are in good agreement. A new peak appearing at 40.83 ppm can be identified as the methine carbon of the H-type sibling, with the other two new peaks at 31.57 and 28.37 ppm corresponding to the adjacent α-CH_2 and β Resonance of carbon on -CH_2. Quantitative studies in this work show that the number of H-type cross-linked points in samples exposed to extra-corneous light for 3 to 5 minutes under vacuum and in molten state is estimated to be 8.5 to 11.0 per 10,000 carbon atoms.