Chinese Journal of Magnetic Resonance >
Solid-State NMR Studies on the Structure and Confined Segmental Dynamics of PMMA Nanocomposite
Received date: 2014-05-01
Revised date: 2015-01-14
Online published: 2015-03-05
Supported by
国家自然科学基金资助项目(21174072)，高等学校仪器设备共建共享资助项目(CERS-1-61).
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
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 . DOI: 10.11938/cjmr20150103
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