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An investigation was carried out on the effects of annealing treatment on the molecular structure and the mechanical properties of isotactic polypropylene fibers annealed in an air heated environment at temperatures ranging from 60 to 140 C. Analysis of the equatorial Xray diffraction traces showed the presence of a three phase system of amorphous-smectic-monoclinic forms and revealed the transformation of the metastable smectic form to the highly stable monoclinic form as the annealing temperature is increased, resulting in an enhanced degree of crystallinity and the crystallite size. The improvements in the degree of crystallinity and the crystallite size became more remarkable above 120 C. Evaluation of the crystallinity was carried out using an analysis of density, infrared spectroscopy, and X-ray diffraction methods whereas the state of the molecular orientation was evaluated using polarized infrared spectroscopy measurements only. Polarized infra-red spectroscopy measurements after the curve fitting procedure showed a slight increase of the molecular orientation of the helical chain segments present in the crystalline phase represented by the IR bands at 841 and 998 cm À1 whereas the amorphous structure represented by the IR band at 974 cm À1 showed no significant change with increasing annealing temperature. The improvement in the molecular orientation of the crystalline phase became more remarkable above 120 C. Tensile strength of the annealed fibers increased with increasing annealing temperature but the elongation at break and the initial modulus were not affected as much as the tensile strength.

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Natural dyes are the heritage of the history to human being. Although they were used for the colouration of goods from the ancient time, it is not common to use natural dyes commercially now. But at least in some special goods it is saving its popularities too. On the other hand, it can be foreseen that the demand on the ecological, natural and organic products in all consumable articles will make natural dyes popular again. Owing to this, it is important to continue the studies on the usability of natural dyes in textile colouration techniques. This study is focused on the printing of natural dyes differently on dyeing with natural dyes. For this aim four different natural sources were used. For the printing process, pigment printing was selected and the printing was managed on wool and cotton fabrics without use of any mordants. The colour values and the fastnesses of prints were evaluated. It was observed that the natural dyes can be used in pigment printing processes and different colour values with different fastnesses could be observed.

Thermally stabilized isotactic polypropylene fibers were developed using sulfonation procedure prior to carbonization stage. Sulfonation was performed to make the fibers infusible, intractable, and insoluble with concentrated sulfuric acid (approx. 95-97% conc.) at a temperature of 120 C for sulfonation times ranging from 0.5 to 8 h. Sulfonation results in highly crosslinked structures which are thermally stabilized thus making the structure suitable to withstand the high temperatures involved in the carbonization stages. Structural characterization of sulfonated polypropylene fiber was carried out using combination of elemental analysis, differential scanning calorimetry, thermogravimetric analysis, and infra-red spectroscopy techniques with the aim of following the structural developments at a molecular level. Precursor fibers sulfonated for sulfonation times of 6 h or longer retained up to 46% of their mass at 1000 C. DSC and IRspectroscopy observations indicate the gradual loss of isotacticity and crystallinity with the progress of sulfonation treatment.