In this study we propose to grow extended chain polymer crystals on individual SWNTs (not on bundles of SWNTs) using shear flow field in an appropriate solvent. The polymer coated SWNTs are termed as ?seed crystals?. Flexible polymers such as polyethylene, polypropylene, PET, nylon 6, and nylon 66 will be used in this study. These seed crystals will be harvested from solutions and characterized by high resolution transmission electron microscopy, wide-angle X-ray diffraction, and by differential scanning calorimeter. The seed crystals will be blended in the respective polymer in melt or in solution. Fibers will also be spun by melt or solution spinning. The idea is to use seed crystals to promote extended chain morphology in those polymers, where only semi-crystalline morphology with chain folds exists. Structure, morphology, and properties of the processed fibers will be studied.
Growth and study of the "seed crystals" will contribute to the fundamental understanding of interaction between polymer and the carbon nanotube. Use of such crystals in polymer processing would provide range of polymer morphologies that would broaden the structure-property relationship understanding. There is a significant performance and price gap between the commodity textile fibers such as PET, nylon, and polypropylene on one hand, and high performance polymeric fibers such as Kevlar® and Zylon® on the other. This study has the potential to close the performance gap between these two classes of fibers. Polymer-CNT seed crystals developed in this study may also find applications in injection molding and extrusion for influencing polymer orientation and crystallization in these processes. In addition polymer coated carbon nanotube seeds can find application in electronics where carbon nanotube act as conductor of heat and electricity and polymer as the insulating layer.
