TY - CONF TI - Alpaca Fiber and NC State AU - Godfrey, Blanton AU - Hergeth, Helmut T2 - Alpaca Fiber Symposium C2 - 2009/4/4/ CY - Textile Technology Center, Gaston College, Belmont, NC DA - 2009/4/4/ PY - 2009/4/4/ ER - TY - CONF TI - The Use of RFIDs in Luxury Products: Results from a Consumer Acceptance Survey AU - Heinisch, Marc AU - Hergeth, Helmut T2 - International Business and Economics Research Conference C2 - 2009/10/10/ CY - Las Vegas, NV DA - 2009/10/10/ PY - 2009/10/10/ ER - TY - CONF TI - Entrepreneurship Education in Textile Management AU - Hergeth, Helmut T2 - International Business and Economics Research Conference C2 - 2009/10/18/ CY - Las Vegas, NV DA - 2009/10/18/ PY - 2009/10/18/ ER - TY - CONF TI - Just Flush it Down the Drain! Industry Technology Roadmapping for Flushable Pre-Moistened Wipes AU - Kim, Mun Jung AU - Hergeth, Helmut T2 - International Business and Economics Research Conference C2 - 2009/10/18/ CY - Las Vegas, NV DA - 2009/10/18/ PY - 2009/10/18/ ER - TY - CONF TI - Fashion, work and disability AU - Carroll, K. AU - Welsh, K. AU - Fox, S. T2 - International Federation of Fashion Technology Institutes Annual Conference- Fashion and Well-Being C2 - 2009/// C3 - Proceedings of the 11th International Federation of Fashion Technology Institutes Annual Conference CY - London College of Fashion DA - 2009/// PY - 2009/3/31/ PB - International Foundation of Fashion Technology Institutes UR - http://iffti.org/downloads/papers-presented/xi-LCF,%202009/Carroll_Kate.pdf ER - TY - JOUR TI - Utilitarian and hedonic shopping value in the US discount sector AU - Carpenter, Jason M. AU - Moore, Marguerite T2 - Journal of Retailing and Consumer Services AB - General merchandise discount retailers in the US have evolved to offer higher levels of hedonic shopping value, thereby intensifying levels of intra- and inter-type competition within the industry. Academic research on consumer reactions to these efforts is limited. This study investigates consumers’ perceptions of utilitarian and hedonic shopping value associated with the two leading US general merchandise discounters. Findings suggest differences in perceptions of the level of hedonic benefits offered by the discounters and provide useful insight for the further development of marketing strategies. DA - 2009/1// PY - 2009/1// DO - 10.1016/j.jretconser.2008.10.002 VL - 16 IS - 1 SP - 68-74 J2 - Journal of Retailing and Consumer Services LA - en OP - SN - 0969-6989 UR - http://dx.doi.org/10.1016/j.jretconser.2008.10.002 DB - Crossref KW - Shopping value KW - Utilitarian KW - Hedonic KW - Discount retailing ER - TY - JOUR TI - Advanced mass customization in apparel AU - Lim, H. AU - Istook, C. AU - Cassill, N. T2 - Journal of Textile and Apparel, Technology and Management DA - 2009/// PY - 2009/// VL - 6 IS - 1 SP - 1–11 ER - TY - SOUND TI - Static Generation and Dissipation of Polyester Continuous Filament Yarn AU - Suh, M. AU - Seyam, A.M. AU - Oxenham, W. AB - The effect of environmental conditions (temperature and relative humidity) and contact conditions (yarn tension and speed) on static generation and dissipation of polyester flat continuous filament yarn, when rubbed against stainless steel was analyzed. A newly developed device, housed in an environmental room, was used to charge the yarn while moving under desired tension. The charge potentials were measured at two different positions in real time. These measurements and previously established exponential relationship permitted the calculation of the initial potential (at the generation point) and a ‘characteristic decay time’, which is a measure of static dissipation. Experimental data showed that temperature, humidity, yarn tension, and yarn speed have significant effects on static generation; while temperature, humidity, and yarn speed yielded statistically significant changes on static dissipation. Anomalous behavior of static charge when measured at a temperature of 35°C, provided a meaningful clue to control the environmental conditions in the textile industry. DA - 2009/7/16/ PY - 2009/7/16/ DO - 10.1080/00405000802377250 M3 - poster KW - electrostatics KW - static charge generation KW - static charge dissipation KW - static charge measurement KW - coefficient of friction ER - TY - SOUND TI - Static Generation and Dissipation in Textiles AU - Suh, M. AU - Seyam, A.M. AU - Oxenham, W. DA - 2009/3/18/ PY - 2009/3/18/ M3 - poster ER - TY - SOUND TI - Rehabilitative Smart Apparel for Wounded Soldiers AU - Park, J.H. AU - Suh, M. AU - McClusky, D. AU - Carroll, K. AU - Fornaro, R. AU - Lee, H.J. DA - 2009/4/21/ PY - 2009/4/21/ ER - TY - CHAP TI - Implications of Participatory Design for a Wearable Near and Far Environment Awareness System (NaFEAS) for Users with Severe Visual Impairments AU - Kim, Si-Jung AU - Smith-Jackson, Tonya AU - Carroll, Katherine AU - Suh, Minyoung AU - Mi, Na T2 - Universal Access in Human-Computer Interaction. Addressing Diversity AB - This paper presents experiences from a study that included five users with Severe Visual Impairments (SVIs), fashion designers, and human factors engineers. We used participatory design (PD) to develop a wayfinding and object-recognition system. The PD study consisted of three sessions and was designed to include actual users in the design process. The primary goal of the PD was to validate the system concept and to determine the attributes of system interaction. Two of the three sessions are discussed here. We obtained several insights from a technological perspective, textile and apparel perspective, and user interface design perspective. Among the results identified, users with SVIs preferred to wear assistive technology unless that was not distracting to the participant or those that came into contact with the participant. Auditory feedback was chosen as a primary modality in user interface design, and we realized that constructing a good pool of PD members is essential to transform actual users’ needs and requirements into the design process. PY - 2009/// DO - 10.1007/978-3-642-02707-9_10 SP - 86-95 OP - PB - Springer Berlin Heidelberg SN - 9783642027062 9783642027079 UR - http://dx.doi.org/10.1007/978-3-642-02707-9_10 DB - Crossref ER - TY - CONF TI - Textiles and Clothing Higher Education in China: Openness and Reform as Dynamics for Development AU - Su, J. AU - Swinker, M. AU - Blood, J. AU - Xu, Y. C2 - 2009/// C3 - International Textiles and Apparel Association’s annual meeting DA - 2009/// ER - TY - JOUR TI - The role of etail quality, e-satisfaction and e-trust in online loyalty development process AU - Kim, J. AU - Jin, B. AU - Swinney, J. T2 - Journal of Retailing and Consumer Services AB - The purpose of this study is to propose and test an integrative model of e-loyalty development process by conceptualizing that e-loyalty is influenced by e-satisfaction, e-trust and multi-dimensional aspects of etail quality. In order to capture the full picture of etail quality, we attempt to cover the complete purchase experience by focusing on four dimensions of etail quality that go beyond website functionality or system quality aspects: fulfillment/reliability, website design, security/privacy and responsiveness. From the 182 usable data obtained, hypotheses are tested using structural equation modeling. The results indicate that the e-loyalty development process is influenced by both e-satisfaction and e-trust. The relationship between e-trust and e-satisfaction is found to be significant as well. Components of etail quality have differing effects on e-satisfaction and e-trust. Evaluation of fulfillment/reliability influences e-satisfaction as well as e-trust. Website design positively influences e-satisfaction while security/privacy has a positive effect on e-trust. However, contrary to our expectation, responsiveness affects neither e-satisfaction nor e-trust. Managerial implications are provided following presentation of the findings. DA - 2009/// PY - 2009/// DO - 10.1016/j.jretconser.2008.11.019 VL - 16 IS - 4 SP - 239-247 KW - E-commerce KW - E-trust KW - E-loyalty KW - E-satisfaction KW - Etail quality ER - TY - CONF TI - Building Marketing Awareness for Cotton among Future Retail Industry Professionals AU - Moore, M. AU - Rothenberg, L. AU - Gibson, F. C2 - 2009/9// C3 - Proceedings of the Academy of Marketing Science/American Collegiate Research Association Joint Conference, 12 DA - 2009/9// ER - TY - JOUR TI - An innovative wood-fiber composite incorporating nonwoven textile technologies AU - Dyk, H. AU - Peralta, P. AU - Peszlen, I. AU - Banks-Lee, P. T2 - Forest Products Journal AB - This article is the first to describe a process of manufacturing engineered wood composites that combine two nonwoven textile technologies: bicomponent fiber and needle punching. Hardwood fiber was blended with 10 percent urea formaldehyde and formed into mats. The mats were sandwiched with polypropylene/polyester bicomponent fibers and then needle punched. Needle punching was done by means of barbed needles that oscillated in a vertical direction with regard to the surface of the fiber mat. The barbed needles mechanically interlaced the bicomponent web to the wood-fiber mat and pulled some of the polymer fibers through the thickness direction of the mat. During hot pressing, the polypropylene sheath of the bicomponent fiber flowed, bonded with adjacent wood fibers, and coalesced with the sheath of the adjacent bicomponent fibers. The mats were pressed until the urea formaldehyde was fully cured. Bending and tensile properties of the needle-punched wood composite were assessed and compared with medium-den... DA - 2009/// PY - 2009/// DO - 10.13073/0015-7473-59.11.11 VL - 59 IS - 11-12 SP - 11-17 ER - TY - PAT TI - Fiber-based nano drug delivery systems (NDDS) AU - Pourdeyhimi, B. AU - Holmes, R. AU - Little, T. J. C2 - 2009/// DA - 2009/// PY - 2009/// ER - TY - JOUR TI - Towards Automation of Color/Weave Selection in Jacquard Design: Model Verification AU - Mathur, Kavita AU - Hinks, David AU - Seyam, Abdel-Fattah M. AU - Donaldson, Robert Alan T2 - COLOR RESEARCH AND APPLICATION AB - Abstract Jacquard woven fabrics are made from colored yarns and different weaves for designing complex pictorial and other patterning effects. The final visualized color effect is the result of assigning weave designs to different areas of the pattern to be created. The current practice in creating Jacquard woven fabric designs is to produce many samples in a trial‐and‐error attempt to match artwork colors. An ability to simulate accurately the appearance of a design prior to manufacture is highly desirable to reduce trial‐and‐error sample production. No automated accurate digital color methodology is yet available to assist designers in matching the patterned woven fabric to the desired artwork. To achieve this, we developed a geometrical model to predict the color contribution of each yarn on the face of the fabric. The geometrical model combined with a Kubelka‐Munk based color mixing model allowed the prediction of the reflectance properties of the final color for a given design. We compared the predicted and experimental values of the reflectance properties for a range of fabrics using the same geometric model with three separate color mixing models. The geometrical model combined with a log‐based color mixing model produced reasonable agreement between predicted and measured ΔE ab , with an average ΔE ab of approximately five. © 2009 Wiley Periodicals, Inc. Col Res Appl, 34, 225–232, 2009 DA - 2009/6// PY - 2009/6// DO - 10.1002/col.20494 VL - 34 IS - 3 SP - 225-232 SN - 0361-2317 KW - geometrical model KW - color mixing model KW - color prediction KW - Jacquard KW - color difference ER - TY - JOUR TI - Dressed for combat AU - Lee, H. J. AU - Willis, C. T2 - Chemistry & Industry DA - 2009/// PY - 2009/// IS - 7 SP - 21-23 ER - TY - JOUR TI - Wireless yarn tension measurement, and control in direct cabling process AU - Shankam, V. P. AU - Oxenham, W. AU - Seyam, A. M. AU - Grant, E. AU - Hodge, G. T2 - JOURNAL OF THE TEXTILE INSTITUTE AB - An online yarn tension sensing and control device has been designed and developed. The system was specifically devised for use in a direct cabling machine, wherein yarn tension in the spindle or pot yarn is highly critical and dictates the uniformity of the cabled yarn. Since a balloon formed by the creel yarn always encompasses the pot yarn in a direct cabling machine, yarn tension measurement using a wired sensor is far-fetched. Accordingly, a wireless yarn tension sensor was developed to address this problem and perform online yarn tension measurement. The wireless sensor can be used as an active monitoring tool for measuring online yarn tension in both component yarns, while the closed loop control system replaces passive yarn brakes used in the current direct cabling machines and executes a control mechanism that can control yarn tension adaptively. The device uses Micro-Electro-Mechanical Systems (MEMS) technology with radio frequency (RF) transmission to effectively carry out dynamic online measurement. The control system in conjunction with the wireless sensor ensures equal tension in the component yarns, resulting in the formation of a uniform cabled yarn with equal lengths of both yarns. DA - 2009/7// PY - 2009/7// DO - 10.1080/00405000701830318 VL - 100 IS - 5 SP - 400-411 SN - 0040-5000 KW - direct cabling KW - MEMS KW - yam tension KW - RF KW - wireless KW - closed loop control ER - TY - JOUR TI - Dispersion of Cellulose Crystallites by Nonionic Surfactants in a Hydrophobic Polymer Matrix AU - Kim, Jooyoun AU - Montero, Gerardo AU - Habibi, Youssef AU - Hinestroza, Juan P. AU - Genzer, Jan AU - Argyropoulos, Dimitris S. AU - Rojas, Orlando J. T2 - POLYMER ENGINEERING AND SCIENCE AB - Abstract Cellulose nanoparticles obtained by acid hydrolysis of cellulose paper were used to reinforce polystyrene composite films. The nonionic surfactant sorbitan monostearate was utilized to improve the dispersion properties of the hydrophilic cellulose in hydrophobic matrix and to prevent the formation of aggregates. Turbidity tests were used to measure dispersion stability of the cellulose crystallites in the hydrophobic solvent used in the composite manufacture. A correlation was found between the dispersion stability in solvent and the formation of aggregates in the polymeric composites. Nanocomposite films were processed using a casting/evaporation technique. Thermal and mechanical properties of processed composites were studied by differential scanning calorimetry (DSC) and dynamical mechanical analyses (DMA), respectively. The results showed that the optimum addition of surfactant produced better dispersion of the cellulose particles in the polystyrene matrix and improved the mechanical properties of the resulting composite due to an enhanced compatibility. POLYM. ENG. SCI., 2009. © 2009 Society of Plastics Engineers DA - 2009/10// PY - 2009/10// DO - 10.1002/pen.21417 VL - 49 IS - 10 SP - 2054-2061 SN - 1548-2634 ER - TY - JOUR TI - Devices for measuring electrostatic generation and dissipation on the surfaces of polymeric materials AU - Seyam, Abdel-Fattah M. AU - Cai, Yiyun AU - Oxenham, William T2 - JOURNAL OF THE TEXTILE INSTITUTE AB - Abstract Dynamic electrostatic generation and dissipation on polymer surfaces are of great importance for materials such as yarns and films. To support fundamental research in this area, innovative devices and experimental techniques that can lead to a better understanding of these phenomena are of obvious academic and industrial interest. This paper reports the development of devices for testing the electrostatic generation/dissipation properties of polymer surfaces. These devices include a tester for assessing moving yarns, a high-resistance system to measure the yarn's linear resistance, a tester for evaluating stationary fabrics or films while rubbing against a moving surface and a contact charge tester for investigating charge generated by contacting of two surfaces. These devices enable the study of the influences of relative moving speed, yarn tension, electrostatic charge properties of yarns, as well as contact pressure, rubbing speed, number of rubbings or contacts on the static charge properties of films. Keywords: electrostaticsstatic charge generationstatic charge dissipationtriboelectrificationstatic charge measurementpolymer surface state Acknowledgements We thank the National Textile Center for funding this research work and Dr. Peter Castle for providing suggestion for the designing and constructing of Faraday tubes. DA - 2009/5// PY - 2009/5// DO - 10.1080/00405000701819840 VL - 100 IS - 4 SP - 338-349 SN - 1754-2340 KW - electrostatics KW - static charge generation KW - static charge dissipation KW - triboelectrification KW - static charge measurement KW - polymer surface state ER - TY - JOUR TI - Combined numerical and experimental investigation on the effect of jet pressure and forming belt geometry on the hydroentanglement process AU - Xiang, P. AU - Kuznetsov, A. V. AU - Seyam, A. M. T2 - JOURNAL OF THE TEXTILE INSTITUTE AB - Hydroentanglement is a mechanical bonding process utilised to produce nonwoven fabrics. A web of loose fibres is put on a forming belt or perforated screen to form an integrated fabric with desired aesthetics by subjecting the web to multiple rows of fine high-pressure water jets. Mechanical performance of hydroentangled nonwovens is determined by the degree of the fibre entanglement, which depends on process parameters. This study presents the results of combined experimental and numerical investigation on the effects of the jet pressure and forming belt geometry on fibre entanglement. Extensive comparisons of simulations with experimental data are reported and analysed to give a clear understanding of the effect of fibreweb and forming belt properties on the critical jet pressure. The modelling results are in good correlation with experimental data for a wide range of jet pressures. The effect of the jet count per unit length on the degree of fibre entanglement is also investigated. DA - 2009/5// PY - 2009/5// DO - 10.1080/00405000701770563 VL - 100 IS - 4 SP - 293-304 SN - 1754-2340 KW - hydroentanglement KW - numerical modeling KW - vorticity KW - critical jet pressure KW - forming belt ER - TY - JOUR TI - Electrospun Nanocomposites from Polystyrene Loaded with Cellulose Nanowhiskers AU - Rojas, Orlando J. AU - Montero, Gerardo A. AU - Habibi, Youssef T2 - JOURNAL OF APPLIED POLYMER SCIENCE AB - Abstract Composite microfibers from polystyrene and cellulose nanowhiskers were produced by electrospinning. The morphology of the microfibers was examined by using scanning and transmission electron microscopies. Surface porosity, unique ribbon‐shapes, and the presence of twists along the fiber axis were observed in the composite microfibers. Thermomechanical properties of processed nanocomposites were studied by differential scanning calorimetry and dynamical mechanical analyses. The reinforcing effect of cellulose nanowhiskers was confirmed as the glassy modulus of electrospun microfibers increased with nanowhisker load. This effect is explained to be the result of mechanical percolation of cellulose nanowhiskers forming a stiff and continuous network held by hydrogen bonding. It is demonstrated that cellulose nanoparticles can be used effectively to reinforce hydrophobic matrices and to produce unique structural properties, enabling new functionalities and properties. © 2009 Wiley Periodicals, Inc. J Appl Polym Sci, 2009 DA - 2009/7/15/ PY - 2009/7/15/ DO - 10.1002/app.30011 VL - 113 IS - 2 SP - 927-935 SN - 1097-4628 KW - cellulose KW - electrospinning KW - mechanical properties KW - microfibers KW - nanocomposites KW - nanoparticles ER - TY - JOUR TI - Economic analysis of US textile production activities under the North American Free Trade Agreement AU - Lim, M. AU - Suh, M. W. AU - Gaskill, L. T2 - JOURNAL OF THE TEXTILE INSTITUTE AB - This economic analysis investigates the US textile industry's output supply and input demand pattern under the influence of North American Free Trade Agreement (NAFTA) and determines the significance of the agreement on the industry. This analysis employs the normalized restricted translog profit model as an analytical tool and introduces a time dummy variable in the model to distinguish the pre- and post-NAFTA years. The outcome of analysis shows the significant but negative effect of NAFTA on the industry's profit performance in the early years of the agreement, probably due to intensified import competition, fall of real output prices, and numerous mill closings. NAFTA, however, is identified as less significant than variable input prices of labor, material, and electricity. The elasticity estimates show the dominant role of maintenance and capital expenditures, followed by textile output and variable input prices in order, in determining the industry's output supply and input demand. Overall, NAFTA is identified as a short-term solution to the US textile industry's fundamental problems of high labor costs and declining price competitiveness. DA - 2009/// PY - 2009/// DO - 10.1080/00405000802125170 VL - 100 IS - 7 SP - 612-625 SN - 0040-5000 KW - economic analysis KW - NAFTA KW - textile production KW - normalized restricted translog profit model ER - TY - JOUR TI - The use of three-dimensional nanostructures to instruct cells to produce extracellular matrix for regenerative medicine strategies AU - Schenke-Layland, K. AU - Rofail, F. AU - Heydarkhan, S. AU - Gluck, J. M. AU - Ingle, N. P. AU - Angelis, E. AU - Choi, C. H. AU - MacLellan, W. R. AU - Beygui, R. E. AU - Shemin, R. J. AU - Heydarkhan-Hagvall, S. T2 - Biomaterials AB - Synthetic polymers or naturally-derived extracellular matrix (ECM) proteins have been used to create tissue engineering scaffolds; however, the need for surface modification in order to achieve polymer biocompatibility and the lack of biomechanical strength of constructs built using proteins alone remain major limitations. To overcome these obstacles, we developed novel hybrid constructs composed of both strong biosynthetic materials and natural human ECM proteins. Taking advantage of the ability of cells to produce their own ECM, human foreskin fibroblasts were grown on silicon-based nanostructures exhibiting various surface topographies that significantly enhanced ECM protein production. After 4 weeks, cell-derived sheets were harvested and histology, immunochemistry, biochemistry and multiphoton imaging revealed the presence of collagens, tropoelastin, fibronectin and glycosaminoglycans. Following decellularization, purified sheet-derived ECM proteins were mixed with poly(epsilon-caprolactone) to create fibrous scaffolds using electrospinning. These hybrid scaffolds exhibited excellent biomechanical properties with fiber and pore sizes that allowed attachment and migration of adipose tissue-derived stem cells. Our study represents an innovative approach to generate strong, non-cytotoxic scaffolds that could have broad applications in tissue regeneration strategies. DA - 2009/// PY - 2009/// DO - 10.1016/j.biomaterials.2009.05.033 VL - 30 IS - 27 SP - 4665-4675 ER - TY - JOUR TI - Melt-Blowing Thermoplastic Polyurethane and Polyether-Block-Amide Elastomers: Effect of Processing Conditions and Crystallization on Web Properties AU - Begenir, Asli AU - Michielsen, Stephen AU - Pourdeyhimi, Behnam T2 - POLYMER ENGINEERING AND SCIENCE AB - Abstract Melt‐blown webs from ester and ether thermoplastic polyurethanes and polyether‐block‐amide (PEBA) elastomers were produced at different die‐to‐collector distances (DCD) to study the correlation between the polymer type and hardness, melt‐blowing process conditions, and web properties. An experimental set up was built to measure the air temperature and velocity profiles below and across the melt‐blowing die to correlate the fiber formation process and polymer crystallization behavior to process conditions and web properties. It was shown that air temperature and velocity profiles follow similar trends with increasing distance below the melt‐blowing die: both drop rapidly until reaching a plateau region approximately 5–6 cm below the die. Thereafter, they remain relatively constant with further increasing distance. It was found that crystallization onset and peak temperatures of all block copolymers in this study fall within this region of rapid velocity and temperature drop. This suggests that the polymers have already started to crystallize and solidify before reaching the collector, the extent of which depends on the crystallization kinetics of the polymer. The strong influence of the crystallization kinetics on web strength was clearly demonstrated in the PEBA series. In particular, the hardest grade produced the lowest web strength mainly because of its high crystallization rate and crystallization onset temperature. It is concluded that the melt‐blown web strength is strongly dependent on the degree of fiber‐to‐fiber adhesion within the web, which is determined by the amount of fiber solidification that occurs prior to the collector. The crystallization kinetics of the polymer and the distances traveled between the die and collector or the exposure time of the polymer melt to process and ambient air were shown to be critical in the amount of fiber solidification attained. POLYM. ENG. SCI., 2009. © 2009 Society of Plastics Engineers DA - 2009/7// PY - 2009/7// DO - 10.1002/pen.21244 VL - 49 IS - 7 SP - 1340-1349 SN - 1548-2634 ER - TY - JOUR TI - Experimental and numerical investigation of the peeling force required for the detachment of fabric from the forming belt in the hydroentanglement process AU - Xiang, P. AU - Kuznetsov, A. V. AU - Seyam, A. M. T2 - JOURNAL OF THE TEXTILE INSTITUTE AB - Abstract Hydroentanglement is a fast-growing process for manufacturing non-woven fabrics. In this process, multiple fine jets of highly pressurised water are directed towards a fibreweb composed initially of loose fibres, supported by the forming belt. The impact of the jets causes fibre entanglement in the fibreweb and produces an integrated fabric with desired aesthetics. It is important that, at the end of the process, the fibreweb could be easily separated from the forming wires. In this paper, the peeling force required for the separation of the hydroentangled fabric from the forming wires is measured experimentally. Numerical simulations of the hydroentanglement process are also carried out to predict the probability of fibres to be pushed in the knuckles of the forming wires. The fibres that get caught in the knuckles are mainly responsible for the peeling force of the fabric from the forming wires. The fibreweb is modelled as a porous layer, which is supported by forming wires. By correlating experimental results with simulations, a mathematical model, which is based on simulating average vorticity around the forming wires, is developed to predict the peeling force. The effect of the thickness of the fibreweb layer on the peeling force is investigated. Keywords: hydroentanglementnon-wovenpeeling forcenumerical simulationforming surfacesfluid vorticity Acknowledgements The support provided by the Nonwoven Cooperative Research Center of North Carolina State University is gratefully acknowledged. Helpful discussions with industry advisors to this project: C. Camelio, R. Holmes, F. Noëlle, Dr D. Shiffler and C.B. Widen, are appreciated. DA - 2009/// PY - 2009/// DO - 10.1080/00405000701679723 VL - 100 IS - 2 SP - 99-110 SN - 1754-2340 KW - hydroentanglement KW - non-woven KW - peeling force KW - numerical simulation KW - forming surfaces KW - fluid vorticity ER - TY - JOUR TI - Analytical expressions for predicting permeability of bimodal fibrous porous media AU - Tafreshi, H. Vahedi AU - Rahman, M. S. A. AU - Jaganathan, S. AU - Wang, Q. AU - Pourdeyhimi, B. T2 - CHEMICAL ENGINEERING SCIENCE AB - Pressure drop is one of the most important characteristics of a fibrous media. While numerous analytical, numerical, and experimental published works are available for predicting the permeability of media made up of fibers with a unimodal fiber diameter distribution (referred to as unimodal media here), there are almost no easy-to-use expressions available for media with a bimodal fiber diameter distribution (referred to as bimodal media). In the present work, the permeability of bimodal media is calculated by solving the Stokes flow governing equations in a series of 3-D virtual geometries that mimic the microstructure of fibrous materials. These simulations are designed to establish a unimodal equivalent diameter for the bimodal media thereby taking advantage of the existing expressions of unimodal materials for permeability prediction. We evaluated eight different methods of defining an equivalent diameter for bimodal media and concluded that the area-weighted average diameter of Brown and Thorpe [2001. Glass-fiber filters with bimodal fiber size distributions. Powder Technology 118, 3–9], volume-weighted resistivity model of Clague and Phillips [1997. A numerical calculation of the hydraulic permeability of three dimensional disordered fibrous media. Physics of Fluids 9 (6), 1562–1572], and the cube root relation of the current paper offer the best predictions for the entire range of mass (number) fractions, 0⩽nc⩽1, with fiber diameter ratios, 1⩽Rcf⩽5, and solidities, 5⩽α⩽15. DA - 2009/3/16/ PY - 2009/3/16/ DO - 10.1016/j.ces.2008.11.013 VL - 64 IS - 6 SP - 1154-1159 SN - 0009-2509 KW - Bimodal media KW - Permeability modeling KW - Fibrous media KW - Filters ER - TY - JOUR TI - Atomic layer deposition and biocompatibility of titanium nitride nano-coatings on cellulose fiber substrates AU - Hyde, G. K. AU - McCullen, S. D. AU - Jeon, S. AU - Stewart, S. M. AU - Jeon, H. AU - Loboa, E. G. AU - Parsons, G. N. T2 - BIOMEDICAL MATERIALS AB - Atomic layer deposition (ALD) is investigated as a process to produce inorganic metallic bio-adhesive coatings on cellulosic fiber substrates. The atomic layer deposition technique is known to be capable of forming highly conformal and uniform inorganic thin film coatings on a variety of complex surfaces, and this work presents an initial investigation of ALD on porous substrate materials to produce high-precision biocompatible titanium oxynitride coatings. X-ray photoelectron spectroscopy (XPS) confirmed TiNOx composition, and transmission electron microscopy (TEM) analysis showed the coatings to be uniform and conformal on the fiber surfaces. Biocompatibility of the modified structures was determined as a function of coating layer thickness by fluorescent live/dead staining of human adipose-derived adult stem cells (hADSC) at 6, 12 and 24 h. Cell adhesion showed that thin TiNOx coatings yielded the highest number of cells after 24 h with a sample coated with a 20 Å coating having approximately 28.4 ± 3.50 ng DNA. By altering the thickness of the deposited film, it was possible to control the amount of cells adhered to the samples. This work demonstrates the potential of low temperature ALD as a surface modification technique to produce biocompatible cellulose and other implant materials. DA - 2009/4// PY - 2009/4// DO - 10.1088/1748-6041/4/2/025001 VL - 4 IS - 2 SP - SN - 1748-605X ER - TY - JOUR TI - Nanofibrous scaffolds electrospun from elastomeric biodegradable poly(L-lactide-co-epsilon-caprolactone) copolymer AU - Chung, Sangwon AU - Moghe, Ajit K. AU - Montero, Gerardo A. AU - Kim, Soo Hyun AU - King, Martin W. T2 - BIOMEDICAL MATERIALS AB - Electrospinning has recently received much attention in biomedical applications, and has shown great potential as a novel scaffold fabrication method for tissue engineering. The nano scale diameter of the fibers produced and the structure of the web resemble certain supramolecular features of extracellular matrix which is favorable for cell attachment, growth and proliferation. There are various parameters that can alter the electrospinning process, and varying one or more of these conditions will result in producing different nanofibrous webs. So the aim of this study was to investigate the effect of material variables and process variables on the morphology of electrospun 50:50 poly(L-lactide-co-epsilon-caprolactone) (PLCL) nanofibrous structures. The morphology of the nanofibers produced was strongly influenced by parameters such as the flow rate of the polymer solution, the electrospinning voltage and the solution concentration. The diameter was found to increase with solution concentration in a direct linear relationship. Finally, it has been successfully demonstrated that by increasing the rotation speed of the collector mandrel, the alignment of the fibers can be controlled in a preferred direction. These findings contribute to determining the functional conditions to electrospin this biodegradable elastomeric copolymer which has potential as a scaffold material for vascular tissue engineering. DA - 2009/2// PY - 2009/2// DO - 10.1088/1748-6041/4/1/015019 VL - 4 IS - 1 SP - SN - 1748-605X ER - TY - JOUR TI - A study on compression-induced morphological changes of nonwoven fibrous materials AU - Jaganathan, S. AU - Tafreshi, H. Vahedi AU - Shim, E. AU - Pourdeyhimi, B. T2 - COLLOIDS AND SURFACES A-PHYSICOCHEMICAL AND ENGINEERING ASPECTS AB - Pore size is a characteristic parameter that is often defined for fibrous materials used in industrial applications. While there exist many available studies on the pore size distribution of different fibrous materials, the influence of compression load on pore size distribution has not been studied well. Studying the behavior of fibrous materials under compression is important especially because in many applications these materials are subjected to some degree of compression during use. In this work, we present a novel image-based modeling technique to study the changes in the pore size distribution of a fibrous material exposed to compressive load. This was made possible by building a miniature compression cell, and imaging the structure of a hydroentangled fabric under varying levels of compression. The 3D images obtained with Digital Volumetric Imaging were utilized to study the pore size distribution of the material and develop an empirical correlation as a function of compressive stress for these structures. This new correlation indicates that the mean pore diameter of a nonwoven material decreases exponentially with increasing the compressive stress. DA - 2009/4/1/ PY - 2009/4/1/ DO - 10.1016/j.colsurfa.2008.12.019 VL - 337 IS - 1-3 SP - 173-179 SN - 1873-4359 KW - Fibrous materials KW - Pore size distribution KW - Modeling KW - Compression KW - 3D imaging ER - TY - JOUR TI - Crystallization Behavior of Elastomeric Block Copolymers: Thermoplastic Polyurethane and Polyether-block-Amide AU - Begenir, Asli AU - Michielsen, Stephen AU - Pourdeyhimi, Behnam T2 - JOURNAL OF APPLIED POLYMER SCIENCE AB - Abstract The isothermal crystallization kinetics of melt‐blown webs produced from a series of elastomeric block copolymers was studied through differential scanning calorimetry (DSC). Three hardness grades were selected for a polyester and a polyether Elastollan® thermoplastic polyurethane and Pebax® polyether‐ block ‐amide copolymers. The Avrami crystallization kinetics parameters, k and n , were derived from two different methods: (1) traditional Avrami model and (2) derivative of the Avrami model proposed by Kurajica et al. (Croat Chem Acta 2002, 75, 693). The kinetic parameters from both models were consistent and showed good correlation. For all polymer types and hardness grades, crystallization kinetics were interpreted with the derivative model (Kurijica et al.) since it could be directly fitted to untransformed DSC isothermal crystallization data, and thus reduces the errors involved in Avrami analysis. The values of the Avrami exponent, n ranged between 2.59 and 3.41, indicating similar nucleation and growth mechanisms. These n values and morphological observations indicate that crystallization occurs in these copolymers in three dimensions from pre‐existing nuclei and the crystals grow under isothermal conditions. This suggests that, in these elastomeric copolymers, crystallization of the hard segments drives microphase separation into crystalline and amorphous regions rather than formation of hard and soft domains. © 2008 Wiley Periodicals, Inc. J Appl Polym Sci, 2009 DA - 2009/2/5/ PY - 2009/2/5/ DO - 10.1002/app.29082 VL - 111 IS - 3 SP - 1246-1256 SN - 1097-4628 KW - polyurethane KW - crystallization KW - Avrami KW - thermoplastic elastomer ER -