Effect of process parameters on properties of polypropylene and kenaf fibres needle-punched nonwoven geotextiles

Effects of stroke frequency, depth of needle penetration and mass per unit area on properties of needle-punched nonwoven fabrics produced from polypropylene (PP), 50/50 PP/kenaf and kenaf fibres have been studied. Properties of fabrics, such as tensile strength, puncture resistance, pore size, water permeability and transmissivity are analysed. Results obtained show that the higher tensile strength and puncture resistance are achieved in fabrics produced from kenaf fibres at higher stroke frequency, depth of needle penetration and mass per unit area. Fabrics produced from kenaf fibres can be employed in geotextile applications, since they also possess bigger pore size and higher water permeability.

Effect of process parameters on properties of polypropylene and kenaf fibres needle-punched nonwoven geotextiles

274-285Effects of stroke frequency, depth of needle penetration and mass per unit area on properties of needle-punched nonwoven fabrics produced from polypropylene (PP), 50/50 PP/kenaf and kenaf fibres have been studied. Properties of fabrics, such as tensile strength, puncture resistance, pore size, water permeability and transmissivity are analysed. Results obtained show that the higher tensile strength and puncture resistance are achieved in fabrics produced from kenaf fibres at higher stroke frequency, depth of needle penetration and mass per unit area. Fabrics produced from kenaf fibres can be employed in geotextile applications, since they also possess bigger pore size and higher water permeability

A review of wound dressings treated with Aloe vera and its application on natural fabrics

Natural wound dressings extracted from Aloe vera leaves have gained greater recognition in the treatment of wounds due to their ability to accelerate wound healing and their nontoxic nature for humans and the environment. Treated wound dressing allows the removal of moisture and movement of gases to and from the wound area while the antimicrobial agent in it suppresses microbial growth. Extracted Aloe vera components can be applied directly into a fabric or they can be electrospun to nanoparticles that are incorporated into the fabric. Because biological antimicrobial agents like Aloe vera are not highly effective against high concentrations of microorganisms, chemical antimicrobial agents are still used even though they are harmful. Processing Aloe vera using methods like the thermal treatment method makes the Aloe vera lose some of its therapeutic benefits. Natural fabrics treated with Aloe vera can be used as an alternative to chemical agents used for wound treatment. Natural wound dressings treated with natural antimicrobial agents have the advantage of preventing microbial growth while at the same time promoting wound healing without activating the immune response as they are biocompatible

Stress-strain characteristics of air-jet textured polyester yams

283-289Stress-strain characteristics of air-jet textured yarn are affected by many factors, including overfeed and constituent feeder yarn properties. After texturing, there is a considerable reduction in tenacity and modulus of yarns. Yarn extension at peak load mostly decreases moderately after texturing. Majority of the textured yarns exhibit catastrophic tensile failure. Core-wetted textured yarns textured with less number of coarse effect filaments exhibit non-catastrophic tensile failure. Normal (parallel-feed) textured yarns are more extensible and have less initial modulus

Micromechanics of hydroentangled nonwoven fabrics

The mechanics of nonwoven fabrics is largely dependent on fiber properties, and other physical factors such as structural arrangement and degree of entanglement of the fibers. In this study, modeled and experimental stress–strain behaviors of uniaxially loaded hydroentangled nonwoven fabrics have been analyzed and compared. The theoretical values from the model were deduced from the measured properties of micro-samples, namely, fiber volume faction, orientation distribution and mechanical properties. Testing of the micro-samples was performed on a Deben Microtest Module fitted in the FEI Quanta 200 Scanning Electron Microscope. The experimental stress–strain results show that the structure is in the linear region when the modeled results approach the highest specific stress. Also, the theoretical models highly overestimate the specific stress of the hydroentangled nonwoven fabrics. The results show that the application of the model was limited in predicting tensile stress. Furthermore, a trapezoid method was used to quantify the actual deformation energy from the stress–strain graphs up to the ultimate tensile strength. The theoretical deformation energy was estimated and compared to the experimental values. The model was subsequently modified to improve its predictive capability

Hairiness reduction in polyester spun yarns during ring spinning using air nozzles — Optimization of nozzle and other parameters

521-528Nozzle and other parameters have been optimized using factorial design approach to reduce the hairiness of ring-spun yarns as the fibre strand coming out of the nip of front roller of ring frame is passed through an air-vortex nozzle before going to the lappet. The parameters, such as axial angle of air inlets in the nozzles, diameter of yarn channel in the nozzle, air pressure supplied to the nozzles and denier of fibres used to spin the yarns, have been considered. The 45° angle for air inlets, 2.2 mm diameter of nozzles, 1.0 denier fibre and 0.9 bar (gauge) air pressure are the best combinations to obtain lowest yarn hairiness when using nozzles during spinning. Computational fluid dynamics model has been used to simulate airflow pattern inside the nozzle. Swirling effect of air, caused by the design of the nozzles, is the main reason behind yarn hairiness reduction. Vortex nature of air along with air velocity is important phenomenon in reducing yarn hairiness. Tensile and evenness properties of Nozzle Ring yarns are almost similar to those of the conventional ring yarns spun without nozzle