Janusz Fabia

DSC, WAXD and SEM studies of biodegradation of poly(L-lactide-glycolide-trimethylene carbonate) shape memory terpolymer

Presented study is a part of structural project devoted to elaborating the basis of manufacturing technology of l-lactide–glycolide–trimethylene carbonate polymer system—a novel full biodegradable and resorbable shape–memory polymers. In this paper we took an attempt to describe the transformation of structure of studied shape–memory terpolymers under the influence of the process of biodegradation that occurred in time of implantation samples using first of all the differential scanning calorimetry and supplementary—the wide angle X-ray diffraction and scanning electron microscopy methods. After a 5-year-period of ageing the distinct increase of crystallinity of fibres was found.

Formation and properties of polypropylene/stearic acid composite fibers

This paper refers to the formation and properties of polypropylene/stearic acid (PP/SA) composite fibers. For the investigation, commercial metallocene-catalyzed PP polymer and SA were used. The fibers were produced in laboratory conditions using the single screw spin draw device. The textile-mechanical properties, surface composition, morphology and supermolecular structure of as-spun fibers were studied. Moreover, the nonisothermal crystallization of the PP/SA blend and melting behavior of fibers were analyzed. In the investigation Fourier transform infrared–attenuated total reflectance, scanning electron microscopy, differential scanning calorimetry and wide-angle X-ray analytical methods were used. The research showed that the PP/SA blend has lower viscosity compared to the pure polymer and that during the PP crystallization phase, separation is induced. SA delays crystallization of PP, and interaction between SA and PP is observed. The as-spun PP/SA fibers have higher linear density, higher elongation at break and slightly lower tenacity compared to fibers produced from pure PP. The fibers contain a structure with high content of mesophase. During fiber formation, SA migrates towards the fiber surface and forms droplets located beneath the surface of the fiber or crystallizes outside in the form of flake-like crystals.

Study of PET fibres modified with phosphorus–silicon retardants

In this study, flame-retardant poly(ethylene terephthalate) (PET) fibres were produced using a high-temperature bath method similar to dyeing fibres with disperse dyes. A mixture of aqueous solutions of silicon and phosphorus compounds was used as the flame retardant. Samples of the modified fibres were examined by thermogravimetric analysis. The residue left after limited oxygen index test was analysed by scanning electron microscopy. Effect of the flame retardant on changing the supermolecular structure of PET fibres was evaluated using wide-angle X-ray diffraction. Mechanical properties of the modified PET fibres as compared with standard fibres were also examined.

Study of Structure of Polypropylene Microfibres Modified with Multi-Walled Carbon Nanotubes

The paper presented is concerned with studies of a supermolecular structure and its transformation during the process of drawing new composite microfibres obtained from isotactic polypropylene (iPP) – as a matrix and multi-walled carbon nanotubes (MWCNT) used as the filler. The nanostructure of iPP/MWCNT microfibres as spun and after drawing at a temperature of 95°C was investigated using scanning electron microscopy (SEM), wide angle X-ray scattering (WAXS), small angle X-ray scattering (SAXS) and differential scanning calorimetry (DSC) methods.