摘要
综述了利用核磁共振波谱(NMR)表征弹性体类高聚物的支化度、支链长度、支链序列分布的方法。核磁共振氢谱可通过甲基的化学位移表征短链支化(<6 C)的支化密度,而核磁共振碳谱可以通过支链点附近C原子的化学位移判断支链类型并计算支化密度,不仅适用于短链支化,还可表征较长链支化(≥6 C)的支化结构,及支链在主链上的序列分布。超长链支化的表征是NMR研究支化结构的盲区。针对文献中报道的某些接枝型支化高聚物的NMR结果,总结并提出了利用核磁共振氢谱计算支化密度及支链长度的方法。
This paper reviews the characterization of branching degree,length and distribution of branches in elastomers with the help of nuclear magnetic resonance(NMR)spectrum.1H-NMR can be used to characterize the branching density of short chains(<6C)by chemical shift of methyl,while13C-NMR is applied to distinguish the branching structure and calculate the density of branches by carbon chemical shift near the branch-point,which applies to characterization of not only short chains but also structure of long chains(≥6C)as well as sequence distribution of branches in main chains.Characterization of very long-chain branching is difficult via NMR.Calculation for branching density and length of branches via1H-NMR is proposed on the basis of NMR results of graft branched polymers in previous literatures.
作者
罗俊杰
卜少华
黄铃
Luo Junjie;Bu Shaohua;Huang Ling(Yanshan Branch of Beijing Research Institute of Chemical Industry(BRICI),SINOPEC, Beijing 102500, China)
出处
《合成树脂及塑料》
CAS
北大核心
2017年第5期92-97,共6页
China Synthetic Resin and Plastics
关键词
核磁共振波谱
弹性体
支化度
支化密度
支链长度
nuclear magnetic resonance
elastomer
branching degree
branching density
length of branch
