低场固体NMR研究纳米复合凝胶结构与动力学

波谱学杂志

低场固体NMR研究纳米复合凝胶结构与动力学

赵守远1，王媛媛1，张荣纯2，陈铁红1，孙平川1*

1. 南开大学功能高分子材料教育部重点实验室，化学学院，天津300071；2. 南开大学物理科学学院，天津300071

收稿日期:2013-04-22 修回日期:2013-05-26 出版日期:2014-06-05 发布日期:2014-06-05
作者简介:赵守远(1987-)，男，浙江温岭人，硕士研究生，主要从事纳米复合水凝胶合成及NMR表征方面的研究. *通讯联系人：孙平川，电话：022-23508171，E-mail: spclbh@nankai.edu.cn.
基金资助:
国家自然科学基金资助项目(21174072)，国家杰出青年科学基金资助项目(20825416).

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

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

1. Key Laboratory of Functional Polymer Materials of Ministry of Education, College of Chemistry, Nankai University, Tianjin 300071, China;2. School of Physics, Nankai University, Tianjin 300071, China

Received:2013-04-22 Revised:2013-05-26 Online:2014-06-05 Published:2014-06-05
About author:*Corresponding author：SUN Ping-chuan , Tel: 022-23508171，E-mail: spclbh@nankai.edu.cn.
Supported by:
国家自然科学基金资助项目(21174072)，国家杰出青年科学基金资助项目(20825416).

摘要/Abstract

摘要：

纳米复合水凝胶复杂的微观结构和动力学决定了其宏观性能，阐明其结构和动力学的非均匀性对揭示凝胶相变机理、认识其宏观物理和化学性质和设计新型高分子凝胶都具有重要意义．通过合成不同粘土含量的系列聚异丙基丙烯酰胺(PNIPAm)/锂藻土纳米复合水凝胶，运用多种先进的低场固体NMR技术详细研究了凝胶微观结构和动力学的非均匀性．首先建立了分析多组分凝胶体系中刚性和柔性高分子组分相对含量的计算方法，然后在不同粘土含量下，通过测量凝胶FID信号和质子T₁定量研究了凝胶中刚性和柔性高分子组分的相对含量；通过偶极滤波双量子NMR实验，研究了体系中与交联密度关联的残余偶极作用参数随黏土含量的变化．结果表明：在纳米复合水凝胶中，随着粘土含量的增加，凝胶中聚合物的刚性相增加，而柔性相下降，当粘土含量达到12% (W_clay/W_water)时体系中的刚性相含量趋于平衡．多量子实验结果表明，随着粘土含量的增加，纳米复合水凝胶中高分子链的残余偶极作用参数逐渐增大，反映了体系中高分子链的受限运动和二维无机纳米片层形成的物理交联密度增大的趋势．

关键词: 低场核磁共振(low-field NMR), 结构与动力学, 温敏高分子, 聚异丙基丙烯酰胺, 纳米复合水凝胶

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

中图分类号:

O482.53

赵守远1，王媛媛1，张荣纯2，陈铁红1，孙平川1*. 低场固体NMR研究纳米复合凝胶结构与动力学[J]. 波谱学杂志.

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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