Comparison of Three NMR Methods for Measuring Crosslink Density of Rubbers

doi:10.11938/cjmr20172571

Abstract

Abstract: NMR is a frequently used technique for measuring crosslink density of rubbers. In this work, three commonly used proton NMR methods for measuring crosslink density of rubbers[i.e., ¹H double-quantum (DQ) NMR, ¹H Hahn echo and ¹H CPMG echo] were compared. Different approaches showed different results, and the origin of such discrepancy was discussed. The echo time dependence of the crosslink density measured with the CPMG echo method was studied. The ways to improve theCPMG echo-based measurements are discussed.

Key words: ¹H CPMG echo, ¹H Hahn echo, ¹H double-quantum (DQ) NMR, natural rubber, crosslink density

CLC Number:

O482.53

GAO Peng-fei, CHU Lin-lin, YANG Yi, JIANG Ji-feng, WANG Jia-chen, YAO Ye-feng, ZHOU Bing. Comparison of Three NMR Methods for Measuring Crosslink Density of Rubbers[J]. Chinese Journal of Magnetic Resonance, 2017, 34(4): 408-420.

References

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