The crystalline structure of polypropylene waxes: An occurrence of [gamma] crystallographic form

The non-regressive interest in application of polypropylene in man-made technologies tends many research groups to further investigate the crystalline structure of that polymer. Current research was focused on the issue of crystallization and supermolecular structure of polypropylene waxes, commonly used in composites technology. With use of Fourier-transform infrared spectroscopy, polarized-light microscopy, differential scanning calorimetry, and wide-angle X-ray scattering, there were described the morphology and crystallinity of two main kind of waxes: thermally degraded and oxidized (both of them treated during various time). The results showed a strong dependence between the method of degradation, as well as its time, and the supermolecular structure of examined waxes. Moreover, the occurrence of significant amount of [gamma] polymorphic form of polypropylene was noticed for degraded waxes samples, especially in anaerobic conditions. It is reasonable to underline that presented kind of research was not published previously and supplied important information about the supermolecular structure of polypropylene waxes. KEYWORDS crystallization, gamma form of polypropylene, polypropylene, polypropylene waxes, supermolecular structure
1 | INTRODUCTION The waxes, well-known and commonly applied substances, are the subject of many investigations related to modification of their properties and applications. The first and still used today [...]