Polymers have been widely used nowadays owing to their versatile properties, which firmly relate to their molecular physical and chemical structures. Therefore, the quantitative and quasi-quantitative characterization of polymer chemical and physical structures is essential in developing novel polymer materials. Among various characterization methods, solid-state nuclear magnetic resonance (SSNMR) plays an essential role in quantitative investigation, which is capable of providing quantitative information on chemical structure of polymers, phase composition of multi-phase systems as well as component content of block copolymers or polymer blends. However, traditional SSNMR quantitative method consumes very long experimental time for most of the systems. Cross polarization (CP) method, as a widely-used SSNMR technique, is capable of providing a spectrum within much shorter time. However, CP is mostly not quantitative. Therefore, several quantitative CP methods were proposed in past years, which are both quantitative and time-saving. In this article, we present an overview of the SSNMR quantitative methods, including the traditional techniques and the newly proposed CP methods in past twelve years. Basic principle and properties of each method are elucidated. In addition, several application examples are introduced which is aimed to assist the researchers in their works of polymer quantitative study.
Contents
1 Introduction
2 SSNMR quantitative techniques and the applications for polymer study
2.1 Direct polarization techniques (DP and DD)
2.2 Cross polarization technique (CP)
2.3 Quantitative CP methods
3 Conclusion