Browsing by Author "Dr. Abdel-Fattah Seyam, Committee Co-Chair"

Filter results by typing the first few letters
Now showing 1 - 2 of 2
  • No Thumbnail Available
    Ionic-Modified Antistatic Finishes: A combination of Nanotechnology and Atmospheric Plasma Treatment
    (2009-08-10) Sarma, Sudhir; Dr. Henry Boyter. Jr., Committee Member; Dr. Ahmed El-Shafei, Committee Member; Dr. Peter Hauser, Committee Co-Chair; Dr. Xiangwu Zhang, Committee Chair; Dr. Abdel-Fattah Seyam, Committee Co-Chair
    The accumulation of static charge on textile material, and its subsequent discharge, presents major problems in the processing of textiles. It also becomes a marketing problem because consumers have to endure the unpleasant effects of static discharge like mild shocks, as well as the clinging and unwanted crumpling of fabrics. To combat the problem of static accumulation, antistatic finishes are added to the substrate. These finishes generally act by adding polar groups to the substrate, increasing the hydrophilicity and making it more amenable to dissipating away the excess charge. This research investigated the effect of silica nanoparticles and ionic monomers on improving the antistatic properties of commercial grade polyester/cotton fabrics. 65%-35% polyester/cotton blended fabrics were treated with combinations of modified silica nanoparticles and ionic monomers like sodium vinylsulfonate and 2-acrylamido-2-methyl-1-propanesulfonic acid. First, the fabrics were exposed to atmospheric plasma to initiate the polymerization reaction on the fabric surface. The fabrics were then coated using a laboratory scale dip-pad process and were either air dried or oven dried depending on whether it was followed up by additional plasma treatment. The finished fabrics were evaluated using a surface resistance meter. The finished fabrics were also tested for durability to laundering. The types of experiments that were carried out ascertained the effect of different processing parameters on the performance of the antistatic finish. The experiments included: (1) application of different concentrations of silica nanoparticles to ascertain the effect of silica concentration on the finish properties; (2) the effect of plasma treatment time on the resulting finish; (3) the effect of plasma types, namely helium and oxygen plasmas, on the resulting antistatic properties; and (4) the effect of plasma treatment procedure on the finish properties. Results of the conducted experiments showed that the modification of the fabric surface using silica particles and ionic monomers yielded the desired results. The antistatic properties of the finished fabrics did show a significant increase after the application of the chemicals, indicated by lowered resistivity values. In addition, the antistatic properties of the finished fabrics improved when they exposed to atmospheric plasma as part of the treatment process, as opposed to just treating the fabric with a combination of polymerization initiators and monomers in the presence of thermal energy. Although the presence of silica particles did have an ameliorating effect on the static dissipating properties, with the best results being noticed at a silica concentration of 0.5 gpl in the dispersion, the antistatic properties decreased first, and then increased sharply as the concentration of silica particles increased in the dispersion. The usage of different gases for plasma also played a role in determining the properties of the finish. Of the two plasma types used: helium and oxygen, oxygen plasma yielded better properties when used in conjunction with silica particles and the ionic monomers. The rinsed samples showed a significant loss in antistatic properties, indicating that the durability of the applied finish needs to be improved. The results obtained would fuel further interest in both the usage of nanosilica and the plasma treatment process to provide inexpensive and environmentally sustainable treatment.
  • No Thumbnail Available
    Static Generation and Suppression in Staple Fiber Yarns
    (2009-04-25) James, Bradley Adam; Dr. Pamela Banks-Lee, Committee Member; Dr. Henry Boyter, Jr, Committee Member; Dr. Abdel-Fattah Seyam, Committee Co-Chair; Dr. William Oxenham, Committee Co-Chair
    JAMES, BRADLEY ADAM. Static Generation and Suppression in Staple Fiber Yarns. (Under the direction of Dr. William Oxenham and Dr. Abdel-Fattah Seyam). Triboelectric effects have been studied since before the times of Christ. In more modern times, the evidence of danger and damage inherent with this phenomenon has become apparent. Much is known and theorized upon about how static electricity is generated, yet there is still much to learn. One of the most widely experienced effects of static buildup is caused by clothing or textile products. Industries worldwide have turned to the textiles markets to develop solutions on combating this nascence. From antistatic chemical treatments to conductive fibers added into processing, many innovative new solutions are still being developed. In order to develop more effective solutions, it is critical to understand more about the triboelectric phenomenon as it relates to the particular materials and substrates in question. Spun yarns are the most widely produced yarns for apparel in the world and are often used in conjunction with antistatic treatments. This research is intended to focus on better understanding some of the variables that affect static buildup and propagation within staple spun yarns. It will specifically focus on understanding the effects of blend, yarn structure, temperature, humidity, and tension as well as variables associated within these factors, such as hairiness and uniformity. This understanding will be developed based on statistically based trails utilizing highly technical equipment specifically developed at NC State and other equipment such as evenness testers and hairiness testers for understanding this phenomenon. Specific tests regarding fiber parameters such as hairiness and oil extractable content from polyester, innovative visual techniques, resistance testing, and voltage measurements all completed within temp/humidity controlled environments will all be used in conjunction to develop theories and understanding into the triboelectric effects of polyester and cotton staple structures. The results indicate that environmental humidity and temperature play critical roles in how staple yarns will perform. Tension plays little role into the charge generated as speed is shown to be the main contributing factor to charge generation. There are also differences observed within yarn structures as well as non-linear relationships between cotton and polyester blends. Specific reasoning has been developed based on supplemental data provided by other non-static measuring on non-electrical measuring tests. The results as well as the measuring processes themselves have led to further fields of interest in this topic which warrant further studies. This information collectively will help in understanding of physical principles of triboelectric charge and developing more effective solutions for combating static buildup as well as providing potential insight into static’s influence in the spinning procedures themselves.