Studies of Domain Morphology of Polymer Blebds by Proton Spin Relaxation Time Distribution

• Main Authors: Lang, Chang-Ling, 郎長齡
• Other Authors: P. P. Chu
• Format: Others
• Language: zh-TW
• Published: 1997
• Online Access: http://ndltd.ncl.edu.tw/handle/11498176148649479123

碩士 === 國立中央大學 === 化學系 === 85 === Solid State NMR has proven its utilities in the studies of polymers, which provide vital information which are not accessible through other measurements. High resolution solid state NMR including arrays of tools such as cross polarization, magic angle sample spinning, multiple pulse, and dynamic angle sample spinning techniques provide molecular detail regarding miscibility and specific interactions between blend components. On the other hand, low field solid state NMR, handicapped with low frequency resolution, is much more powerful in resolving the time domain information. Taking advantage of this character, we have developed a method to reconstruct proton spin-lattice relaxation time distribution using low resolution solid state NMR which shows . The features of the distribution profile provide information regarding the heterogeneity of domain, structure, morphology and molecular dynamics present in polymer blend systems. The present study will demonstrate the usage of T1 spin-lattice time distribution profile method on the study of morphological changes in two polymer blend systems. The first system composed of immiscible blends of PVDF and syndiotatic Polystyrene where the miscibility, re-crystallization, and phase separation kinetic under various curing temperature and blending conditions will be studied via proton T1 spin-lattice time relaxation distribution. The second system pertains to the polymer solid electrolyte where the detail changes of PEO crystallinity upon doping with various degree of Li+ cation concentration is studied by proton spin lattice relaxation time distribution. These results revealed the kinetics and dynamic change of the polymers blends are either hard to obtain or no accessible through conventional measurements.The present results have fully demonstrated the versatilities, convenience, sensitivity, and effectiveness of proton spin lattice relaxation time distribution method in the study of polymer blend systems. The legitimacy and limitation of this method in the study of polymer morphology would be thoroughly examined.