Solid-State NMR Studies on the Structure and Confined Segmental Dynamics of PMMA Nanocomposite

doi:10.11938/cjmr20150103

Abstract

Abstract:

Solid-state NMR techniques were used to study the structure and confined dynamics of poly-methyl methacrylate (PMMA)/laponite nanocomposite. ¹H magic angle spinning (MAS) spectra and relaxation experiments indicate that organic modifiers (AIBA) interact strongly with laponite nano-sheets, and the structure of PMMA nanocomposite is homogenous at the scale of several nanometers. The results of ¹³C spin-lattice relaxation times (T₁,C) experiments indicate that mobility of the PMMA segments, especially the carbonyl groups, in nanocomposite decreases under the confinement of laponite nano-sheets. ¹³C SUPER experiments further indicate that the incorporation of laponite induce a slight change of the CSA line shape of PMMA carbonyl groups.

Key words: solid-state NMR, structure, dynamics, PMMA, laponite, nanocomposite

CLC Number:

O482.53

LIU Yuan，CHEN Sheng-li，WU Qiang，CHEN Tie-hong，SUN Ping-chuan. Solid-State NMR Studies on the Structure and Confined Segmental Dynamics of PMMA Nanocomposite[J]. Chinese Journal of Magnetic Resonance, 2015, 32(1): 23-32.

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