Journal of Textiles and Polymers
Volume:10 Issue: 2, Spring 2022

Surface modification is one of the most techniques to improve the performance of thin film composite polyamide membrane (TFC). In this study, 0.5, 1, and 1.5 w/v% concentrations of the second generation of poly(amidoamine) dendrimer polymer (PAMAM, G2) were utilized to investigate the improvement of membrane performances. Physicochemical properties of the pristine and modified membranes were characterized using water contact angle measurement, ATR-FTIR, and SEM. Membranes separation performance was examined in a forward osmosis system using synthetic brackish water. 1% concentration of PAMAM (TFC-1% PAMAM) was considered as the optimized modified membrane with the best water flux and salt rejection results. According to the results, the water flux of TFC-1% PAMAM compared to that of pristine TFC decreased, while the salt rejection increased, respectively. In addition, passive chlorination tests were performed for pristine TFC and TFC-1% PAMAM. It was observed that the water flux for the unmodified TFC increased from 5.0±1.1 to 5.8±0.8 (16% increased). In contrast, the water flux for TFC-1% PAMAM increased from 4.7±0.6 to 4.9±0.6 (4% increased). Salt rejection for unmodified TFC decreased from 97.6±0.9 to 93.7±1.5 (4% decreased) and for TFC-1% PAMAM decreased from 98.5±0.3 to 95.5±1.2 (3% reduction). The results confirmed the membrane performance improvement after surface modification by PAMAM. The enhanced chlorination resistance of TFC-1% PAMAM was attributed to the scavenger role of the extra amine and amide groups in PAMAM

It is very important to maintain the health and resistance of the military and security forces against bulletsand fragments from explosions on the battlefields. Due to the increasing development of technology formaking weapons and ammunition and the need to increase the efficiency and comfort of personal armorin order to be able to use them more and more widely, research and development in this field has alwaysbeen ongoing. In order to focus and macro-policy at the national level, the development of science andtechnology development strategies for protective layers against bullets and fragments from explosions istargeted in this study. For this purpose, using the SWOT analysis method and obtaining the opinion of theelites in this field, the required strategies have been extracted. The strategies obtained in order of priorityinclude increasing international interactions to supply raw materials for the production of bulletprooflayers, expanding research and development in universities and research centers, improving defense inthe field of military protection, more attention to domestic production and self-sufficiency in advancedfiber production and other materials are needed to make bulletproof layers and to raise the awarenessof government officials, managers and policymakers about advanced fibers. Paying attention to thesestrategies can put all ongoing research activities related to the future of this field in a logical direction,prevent duplication and by creating structures and incentives, lead to the growth and development ofbulletproof layers technology in the country

Nanofibers have attracted a lot of interest in the biomedical field, specifically in nanoscience and nanotechnology. It is challenging to use electrospinning for the achievement of novel nanofibrous composites by the use of inorganic precursors without beads and with a uniform diameter. In this research, the development of biocompatible conjugate electrospinning nanofiber membranes containing zeolite was studied. Nanofiber membranes based on polyestersulfone as the first component and polyvinyl alcohol loaded with zeolite as the second component were prepared using the conjugate electrospinning method. Smooth, uniform nanofibers without the beads containing zeolite in the polymer substrate were observed by scanning electron microscopy (SEM). Conjugate electrospinning nanofiber membranes showed good tensile strength (3/42 MPa) and elastic modulus (48/5 MPa) after thermal crosslinking. In addition, the contact angle was reduced by the addition of polyvinyl alcohol/zeolite, which could eliminate the limitations of polyethersulfone-based membranes due to their high hydrophobicity. The MTT results and cell culture also showed that the polyester sulfone/polyvinyl alcohol-zeolite conjugate electrospinning nanofiber scaffolds made in this study have excellent biological and non-toxic compatibility for the growth of L929 fibroblasts. Therefore, PES/PVA-zeolite conjugate electrospinning nanofiber membranes can provide biomedical applications.

Water, as a necessary liquid for life and an essential source of industries, must be used and recycled in aregular cycle. Water filtration is a special area that is being developed by relevant experts. In many areasof activity, the most critical goal is to increase the separation and filtration efficiency. The efficiency ofan effective filtration system chiefly depends on the selection of a suitable porous filter. Woven fabricsare utilized as filters in liquid filtration. In this research, a water filtration unit was carefully designed andassembled to evaluate woven polyester fabric’s filtration efficiency in a standard procedure. The particlesize distribution in water was between 100-140 μm. The woven polyester fabrics, that were differed inweft density and weave, were produced by a projectile weaving machine. The samples were used as filterson both sides of the back and face of the fabric. After the separation process, the filtered water turbidityand the filtration efficiency for each sample were evaluated. Statistical analysis of the results showed thatthere was a significant difference in filtration efficiency when using low-density fabric samples on bothsides of the back and face of the fabric. The water filtration efficiency when using the backside of thesamples is higher than that when using the face side. In fabric filters with different weave structures anddensities, it was detected that the filtration efficiency is not significantly the same. Finally, according tothe ultimate performance of fabric filters in the filtration process, the samples were classified.

Rug is one of the cultural and artistic symbols of Iran, which is several thousand years old and is used asan exquisite flooring or to decorate the interior of various places. Nevertheless, this art work has acousticproperties due to the high volume of fibers and thickness. Therefore, in this paper, first a new structureof the rug is introduced and then its acoustic properties are evaluated and modeled. The structure ofthe new Double Base Persian rug is similar to the structure of a regular rug, and the only difference isthat there are two sets of warp yarns (instead of one) with a certain distance. In order to investigate theeffect of double bases and also the presence of various materials with different percentages in the gapbetween the two bases on the sound absorption of the new rug, different samples were produced. It isworth mentioning that the effect of the presence of pile on the sound absorption of the new rug has beeninvestigated. The sound absorption of the samples was measured using an impedance tube method and theJohnson-Champoux-Allard model was used to model the sound absorption of the samples. The obtainedresults showed that although the kind of filler material has a little effect on sound absorption, the soundabsorption increases by filling the gap between the two bases and by increasing the filling percentage.The Johnson-Champoux-Allard model also indicated a very good agreement with the experimental data.

Three-layer woven fabrics with two warp and three weft systems are considered as thick fabrics, in whichthe third wadded weft yarn group is used to increase the thickness, to color separate two layers, and tostitch the top and bottom layers. The purpose of this study was to investigate the effect of changing theweave pattern and the count of wadded weft yarn in the fabric structure on the physical properties of thefabric including air permeability, thickness and compression energy, thermal resistance and water vaporpermeability. In this research, weft wadded yarns with the fineness of 24/2, 36/2, and 48/2 Nm and weavestructures of “plain-plain”, “twill 2/2- twill 2/2” and “twill 2/2- plain”, in the top and bottom layers, wereused for fabric production. After the production of fabrics, experiments were performed to investigatethe effect of the wadded yarn fineness and the weave structure on the physical properties of the fabrics.Analysis of the results showed that in comparison of various weave structures, the “plain-plain” had thehighest air permeability and water vapor permeability and the least thickness and heat resistance. “Twilltwill”showed the maximum thickness and heat resistance and the lowest amount of air permeabilityand water vapor permeability. In view of the effect of wadded yarn count, it was found that the 24/2 Nmyarn had the highest air and water vapor permeability, and the lowest thickness and thermal resistance.The 48/2 Nm yarn had the maximum thickness and thermal resistance and at the same time exhibited theminimum air and water vapor permeability.