The results of the nanostructure investigations of selected polymers in non-isothermal conditions are presented. The main interest is focused on the formation and changes of the supermolecular structure during dynamic melting and crystallisation processes. The wide group of polymers including polyethylene, homogeneous ethylene copolymers, isotactic polypropylene (iPP), liquid crystal oligoester (LCO) and LCO-iPP blends were taken as the material for investigation.
These were chosen in view of the fact that both homogenous ethylene-l-alkene copolymers as well as liquid crystal oligoester are new polymers of great significance for industrial practice. The new type of polymer obtained from liquid crystal oligoester and isotactic polypropylene is of particular importance for materials science; this is one of the first such materials obtained from a thermoplastic polymer and a liquid crystal polymer with a low melting temperature, which enables it to be processed from a melt while exploiting the unique properties of the liquid crystal state.
The research carried out shows that the nanostructure of the polymers investigated is complex and depends on thermal conditions. This in turn means that both the qualitative and especially the quantitative description of the nanostructure require using of complementary research methods. The methodology, which is of particular significance in this respect, is that which combines small-angle X-ray scattering (SAXS) with wide-angle X-ray diffraction (WAXD) and differential scanning calorimetry (DSC). Real-time dynamic SAXS and WAXD measurements were performed using synchrotron radiation with very high beam intensity and very fast position sensitive detectors. This meant that distributions of intensity of radiation scattered over both angle ranges could be simultaneously recorded at very short time (for each sample 156 SAXS and WAXD curves were recorded).
This paper was supported by KBN - Grant No 7 T08E 027 20