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[en] Two factors of coating process of 100% polyester fabric with irradiated natural latex which content 10 phr (part hundred ratio of rubber) of isocianate i.e. time curing of 1, 1.5, 2, 2.5 minutes and total number of coating 1, 2, 3 times have been carried out. The importance properties of raining coat i.e. percentage of water absorption, hydrostatic pressure and pull strength have been evaluated. The results showed that by increasing of curing time and number of coating the hydrostatic and pull strength of polyster coated fablic increases, and the percentage of water absorption decrease. The polyster fabric coated by irradiated natural with the film thickness of 40 micron (two times coating), and the curing time of 2.5 minutes at 150 Celcius centigrade, can produce raining coat fabric as well as required. (authors). 7 refs, 3 figs, 2 tabs
[en] Compete text of publication follows. The capillary guiding phenomena is a result of a self-organizing process governing the charge deposition by the incident ions at the inner wall of the capillaries. The ions are deflected by charge patches so they do not suffer close collisions with the capillary wall, even when the capillary axis is tilted with respect to the incident beam direction. This 'fully elastic' guiding has been found to be significant in capillaries of different sizes and aspect ratios, made from different insulator materials, in a wide range of impact ion energies and charge states. In this work, guiding 3-keV Ne7+ ions through nanocapillaries in insulating polyethylene terephthalate was investigated as function of the capillary diameter. The experiments were conducted at the ZERNIKE-LEIF facility at the KVI Groningen (Netherlands). Highly parallel capillaries with a density of 4 x 106 cm2 and diameters of 100, 150, 200, 300, and 400 nm were utilized. The characteristic charges governing the charge evolution of the total ion yield were found to be independent of the capillary diameter. However, certain dynamic properties were found to change significantly with this diameter: The transmission profiles of the 100 nm capillaries are broad and structureless, whereas those for 300 nm are composed of three peaks and the mean angle oscillates with deposited charge. At equilibrium the total ion yield was studied as a function of the tilt angle. The results were used to evaluate guiding angles (see Fig. 1 (b)), which were found to be almost constant near 5.5 deg with varying capillary diameter similarly as the characteristic charge governing the charge evolution. Model considerations were applied to interpret the results. They have led to the conclusions that the effective potential and the capacity of the capillary samples are nearly independent on the diameter. These unexpected results imply the need for further investigations. Acknowledgements. B.S. and Z.J. were supported by the Hungarian National Science Foundation OTKA (No. K73703 and No. PD050000). The work was financially supported by the European Network ITS-LEIF RII3- 026015.
[en] The kinetics of nonisothermal crystallization of three different types of linear aromatic polyester, namely poly(ethylene terephthalate) (PET), poly(trimethylene terephthalate) (PTT), and poly(butylene terephthalate) (PBT), which are different in their number of methylene groups (i.e. 2, 3, and 4 for PET, PTT, and PBT, respectively), was investigated using differential scanning calorimetry (DSC). Analysis of the data was carried out based on the Avrami, Tobin, Ozawa, and Ziabicki models. It was found that the Avrami model provided a more satisfactorily good fit to the experimental data for these polyesters than did the Tobin model. The Ozawa model was found to describe the experimental data fairly well. The Ziabicki's kinetic crystallizability parameter G for these polyesters was found to be of the following order: PBT>PTT>PET. The effective energy barrier for nonisothermal crystallization process of these polyesters, determined by the Friedman method, was found to be an increase function with the relative degree of crystallinity
[en] Two types of unsaturated polyester have been prepared according to normal alkyd methods of preparation. In this work the emphasis has been given to the preparation methodology of unsaturated polyesters in styrene. Their molecule weight distributions fall between normal alkyd's i.e. 2500 to 3500. (author)
[en] A comparative study between the standard Washburn macroscale method for determination of the capillary wetting rate in a nonwoven textile fibre mesh and the polarization optical video-microscopy-based microscale method for investigation of the wetting process in single fibres is reported. The study was performed with profiled polyester fibres associated with superior wicking performance. Both methods resulted in very similar values of the wetting rate, which confirms that for textile materials based on such type of fibres the microstructure of a single fibre dictates liquid transport properties on the micro- as well as on the macroscale. Consequently, for such materials the microscale method is fully competitive with the standard macroscopic approaches. (paper)
[en] The effect of grafting acrylic acid (AA), N-vinyl pyrrolidone (NVP) and their mixture on the hydrophilic, electrical, dyeing, and mechanical properties of polyester (PET) fabric has been studied. Grafting improves significantly the moisture content (MC), the water sorbency (WS) and the electrical conductivity (EC) of the fabric. Salt treatment of AA and AA/NVP-g-PET causes further increase in the MC, WS and EC. The dyeability of the fabric towards basic Rhodamine Red (RR), direct Congo red (CR) and Disperse Red (DR) dyes is improved by grafting. The tensile parameters revealed the deteriorating effect of grafting.
[en] Fabric Porosity is an important property in determining the functional properties of a fabric. It relates to the count of a yarn as well as to the type of weave. Twill and satin cotton woven fabrics in three different weft densities (warp density kept constant) were used to investigate the effect of porosity on the dye-uptake within one weave. The effects of change in weave type, keeping yarn densities the same, on the porosity were also investigated. Objective determination of porosity was carried out using an image analysis technique while, colour yield was determined using K/S values. Higher the weft density in a satin fabric low will be the porosity of that fabric. Porosity values varied from 6.85-10.98% for Sl and S3 respectively. However, for the twill fabric no substantial change in porosity have been observed as the porosity values varied from 6.4-5.3% for Tl and T3 respectively. Colour strengths for SI and Tl are lower than S3 and T3 respectively for all the primary colours at 0.25,1.00 and 2.00% depth levels. It is observed that the change in colour strength is more prominent at 2 % depth level as compared to 0.25% depth level. (author)
[en] Air-jet texturing of conventional poly(ethylene terephthalate) (PET) yarns, having the same chemical structure with high modulus and tenacity PET yarns, are studied in order to improve their adhesion to rubber. Air-jet texturing of these yarns is performed without any visible loop formation in order to minimize the mechanical loss, and an improvement in the adhesion to rubber of conventional PET yarns is achieved. This improvement is investigated by means of surface changes of single filaments and yarn geometry changes due to air-jet texturing. Changes of the cross-sectional structure of the yarns after air-jet texturing and therefore a higher surface area is found to be the main reason for this improvement