Low-Field NMR Studies on the Structure and Dynamics of Nanocomposite Hydrogels

Abstract

Abstract:

The macroscopic properties of soft matters are largely determined by their composition and the molecular mobility of each component. In this work, we used low field solid-state NMR to study the composition and dynamics of nanocomposite hydrogels with different clay contents. It was found that the content of rigid phase increased, while and the content of soft phase decreased with increasing clay content. A turning point of 12% W_clay/W_water was found, above which the content of rigid phase tended to be a constant. The dipolar coupling constants were measured with double-quantum (DQ) experiments, and the results showed that the confinement of polymer chains and the crosslink density increased with the clay content.

Key words: low-field NMR, structure and dynamics, temperature-sensitive polymer, PNIPAm, nanocomposite hydrogels

CLC Number:

O482.53

ZHAO Shou-yuan1，WANG Yuan-yuan1，ZHANG Rong-chun2，CHEN Tie-hong1，SUN Ping-chuan1*?.

Low-Field NMR Studies on the Structure and Dynamics of Nanocomposite Hydrogels

[J]. Chinese Journal of Magnetic Resonance.

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