Transient NOE driven signal enhancement of INADEQUATE solid-state NMR spectroscopy for the structural analysis of rubbers  

作　　者：Zhiwei Yan Yue-Qi Ye Rongchun Zhang 

机构地区：[1]South China Advanced Institute for Soft Matter Science and Technology(AISMST),School of Emergent Soft Matter(SESM),South China University of Technology,Guangzhou,510640,China [2]JEOL(Beijing)Co.,Ltd.,Haidian District,Beijing,100190,China [3]JEOL Ltd.,Musashino,Akishima,Tokyo,196-8558,Japan [4]Guangdong Provincial Key Laboratory of Functional and Intelligent Hybrid Materials and Devices,South China University of Technology,Guangzhou,510640,China

出　　处：《Magnetic Resonance Letters》2024年第3期35-41,共7页磁共振快报（英文）

基　　金：support of National Natural Science Foundation of China(No.22173033,and 22241501);Natural Science Foundation of Guangdong Province,China(No.2023A1515011395).

摘　　要：INADEQUATE(Incredible Natural Abundance DoublE QUAntum Transfer Experiment)is one of the most important techniques in revealing the carbon skeleton of organic solids in solid-state NMR spectroscopy.Nevertheless,its use for structural analysis is quite limited due to the low natural abundance of^(13)C-^(13)C connectivity(~0.01%)and thus low sensitivity.Particularly,in semi-solids like rubbers,the sensitivity will be further significantly reduced by the inefficient cross polarization from 1H to^(13)C due to molecular motions induced averaging of^(1)H-^(13)C dipolar couplings.Herein,in this study,we demonstrate that transient nuclear Overhauser effect(NOE)can be used to efficiently enhance^(13)C signals,and thus enable rapid acquisition of two-dimensional(2D)^(13)C INADEQUATE spectra of rubbers.Using chlorobutyl rubber as the model system,it is found that an overall signalto-noise ratio(SNR)enhancement about 22%can be achieved,leading to significant timesaving by about 33%as compared to the direct polarization-based INADEQUATE experiment.Further experimental results on natural rubber and ethylene propylene diene monomer(EPDM)rubber are also shown to demonstrate the robust performance of transient NOE enhanced INADEQUATE experiment.

关 键 词：Transient NOE INADEQUATE Carbon skeleton RUBBERS 

分 类 号：O482.532[理学—固体物理]