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In an attempt to increase the biodiversity of natural fibers, new sources of natural fibers should be discovered. Long textile-grade date palm (DP) fibers were used in the manufacturing of 50:50 polypropylene nonwoven composite. DP fibers are considered newcomers to the natural fiber library. The main aim of this work was to benchmark different types of DP fiber composites in comparison to other commercial leaf fiber composites, namely, sisal, abaca, and banana, in addition to FlexForm automotive composites. The composites were mechanically and physically characterized in order to determine their properties. The results showed that the void content in DP composites was lower than that in sisal and abaca by 33% and 40% respectively. DP composites have tensile strength within the same range as sisal composites and higher than that of banana by nearly 33%. The modulus of elasticity and failure strain of DP composites were nearly 3 GPa and up to 3% respectively. The flexural strength of DP composites (35 MPa) was in the same range as that of sisal and abaca. The normalized impact energy of DP composites was higher than that of banana by 50%. The dynamic mechanical analysis of the six composites showed similar behavior with a glass transition temperature around 10 °C. Finally, the water absorption behavior of DP composites was better than the other composites (lower than sisal by 63%). The results showed that DP fibers are good candidates for applications in automotive interior composites, given their competitive performance and high potential availability.

The development of hull material with ideal properties to meet all the operation requirements has posed the greatest challenge to flying the airship at high altitude for extended periods. Materials developed in our previous study with a laminated structure achieved high strength-to-weight ratio and excellent gas barrier property at a relatively low total weight. To optimize this novel design and obtain a more comprehensive understanding of the laminate properties, a parametric study involving lamination process parameters (temperature and time), and laminate structural parameter (reinforcement fabric construction), was conducted. The effects of lamination parameters on tensile, peel, tear and helium permeability tests were carried out to assess the laminates. It was found that the tensile strength of the laminate is predominantly determined by the fabric reinforcement material properties. The peel and tear strength results showed that increasing the lamination temperature from 185 °C to 200 °C improved respective strength values. Additionally, the analysis of failure modes and tear propagation suggested that laminate samples with progressive failure have better tear resistant property over those with brutal failure. Extremely low helium permeability was achieved, yet the gas barrier property was not affected by the lamination process parameters and fabric type.

In this work, fiber-reinforced laminates for the envelope (hull) of high-altitude airships were developed using a novel design concept utilizing ethylene vinyl alcohol (EVOH) as the adhesive compon...

Over the past few decades, ecological concerns resulted in an interest in using natural fibers such as flax and hemp as a reinforcement in composite materials. However, the inherent variability of ...

Recent advancements in 3D printing involve reinforcing the polymer matrix with high-strength fibers offer improved mechanical properties over unreinforced polymeric materials. The fiber-reinforceme...

The present research investigated previously unexplored attributes of 3D printed continuous fiberglass reinforced Nylon composites, Drop-weight and pendulum (Charpy and Izod) impact resistance incl...

Fiber-reinforced 3D printing (3DP) technology is a recent addition to the material extrusion-based 3DP process unlocking huge potential to apply this technology for high-performance material fabrication with complex geometries. However, in order to take the full advantage of this technology, a comparative analysis with existing technologies targeting a particular application is necessary to understand its commercial applicability. Here, an applied composite part, ring-spinning travelers, has been developed using the unique design features of fiber-reinforced 3DP technology that is beyond the capability of the currently used technology, the injection molding, quality, and performance of the printed and molded travelers were investigated and compared. The results demonstrated that fiber-reinforced 3DP is a promising technology that offers a lot of flexibility regarding reinforcement patterns and materials including both short and continuous fibers to tailor the performance, although the printed travelers showed poorer surface characteristics and wear resistance than the molded travelers. Based on the present analysis, a number of recommendations have been proposed on the design of the traveler to apply the technology effectively and use the printer to improvise and manipulate the performance of the travelers.

The effect of different concentrations of Hydroperm T (a hydrophilic surface finishes) on the electrostatic charging and decay properties of filament polyester fabrics, has been investigate...

Dyeing cotton fabrics with anionic dyes produces high effluent loads and requires a considerable amount of water and energy due to the electrostatic repulsion with cellulose. Therefore, several approaches have been researched to increase the efficacy of cotton dyeing. One is the cationization, which adds cationic sites to the cellulose. Another is the treatment of the cotton surface with plasma. In this paper, the combination of both techniques was investigated. Two commercially available cationic agents were used: 3-chloro-2-hydroxypropyl trimethyl ammonium chloride (CHPTAC) and poly[bis(2-chloroethyl) ether-alt-1,3-bis[3-(dimethylamino)propyl]urea] quaternized, a novel cationic agent also known as Polyquaternium2 (P42). The plasma treatment was performed using a dielectric barrier discharge atmospheric plasma facility, helium was used as seed gas and 1.5 % of oxygen was injected. The cationization and plasma treatment were performed on greige cotton fabric, an innovative and sustainable approach that eliminates conventional scouring and bleaching processes. The cationic and plasma treated samples were dyed using Reactive Red 195 and Acid Blue 260 dyes. The effect of the treatments was evaluated by different characterization techniques such as X-ray photoelectron spectroscopy (XPS), Fourier transform infrared spectroscopy (FTIR) and atomic force microscopy (AFM). The plasma treatment slightly increased the light fastness for some samples, but the cationization tends to prevail over the plasma treatment. The best results were attributed to the samples pretreated by CHPTAC, which presented the highest K/S and lowest unlevelness for samples dyed with reactive and acid dyes. CHPTAC is the most common cationic agent for textiles, but its industrial use is limited due to safety criticisms. The combination between plasma and P42 resulted in the same color strength as the conventional reactive dyeing. Therefore, this approach offers a safer alternative to the conventional cationization process.

Cellulose microfibrils (CMFs) and micronized rubber powder (MRP) can be derived from low or negative-cost agricultural/industrial waste streams and offer environment-friendly and cost-effective pathways to develop engineering products. This study investigated the efficacy of adding these micromodifiers on the performance characteristics of asphalt binders. In this work, samples were produced using a mixture of slow-setting anionic asphalt emulsion with various combinations of MRP (at 0, 2 and 10 wt %) and four types of CMFs (hydrophobic and hydrophilic with crystalline ratios of 86% and 95%) at 0, 2 and 5 wt %. The performance of modified asphalt samples was assessed by penetration depth (PD), softening point (SP), and penetration index (PI). Linear regression analysis showed that adding CMFs and/or MRP reduced PD and increased SP values. The type of CMFs significantly affected the performance, which becomes more distinct with the increased weight content of CMFs. While hydrophilic CMFs caused increases in SP and PI values, no clear trend was seen to determine the effect of CMF crystallinity. It was also discovered that the combined addition of CMF and MRP achieved similar PI values at lower total weight content compared to using MRP alone.

The results of a study of charge generation and decay for range of woven fabrics from ring spun cotton yarns, ring spun polyester yarns, and flat continuous filament polyester yarns treated with topical finishes are reported. The topical finishes include commercially available ionic antistatic finishes, one commercially available hydrophilic finish, and a new experimental moisture management finish. The fabrics were rubbed against surface of steel and Polytetrafluoroethylene (PTFE; Teflon®) and their frictional electrification and charge dissipation were monitored. It is shown that fabrics from cotton have a more rapid inherent charge decay than fabrics from polyester. Ionic antistatic finishes are shown to be effective in reducing charge generation and promoting charge decay and this is particularly true for the fabrics made from filament polyester. When commercially available and experimental hydrophilic finishes were applied on fabrics made from filament polyester, less charge was generated and...

Tururi (Manicaria saccifera Gaertn.) is a natural fibrous mesh which protects the fruits of the Amazon Ubucu palm tree. This research targets developing natural fiber composites from Tururi...

Development of three-dimensional (3D) weaving technology introduced new and enhanced features to the 2D weaving technology. 3D Orthogonal Woven (3DOW) preforms have a through-thickness yarn component that significantly enhances the out-of-plane properties and delamination resistance. In this study, a range of 3DOW E-glass preforms were woven using 3D weaving technology and then converted into composites, using vacuum assisted resin transfer molding technology. The composite samples had varying Z to Y-yarn/ layer ratio, the objective is to study the effect of changing the Z to Y-yarn/ layer ratio on the in-plane and out-of-plane mechanical properties. The study concludes that changing the amount of Z-yarn in the structure has negligible effect on the tensile (in-plane), yet, it has a significant effect on the drop weight impact properties (out-of-plane). Moreover, it had a strong effect on the failure mechanisms, and as the amount of Z-yarn is reduced, delamination became more significant.

Over the past few decades, there have been an increasing interest in woven preforms as a reinforcement for composites. The invention of 3D Orthogonal Weaving (3DOW) technology introduced new and en...

E-textiles contain electrically conductive elements and electronic devices that are integrated in textile substrate. Wearable e-textiles are expected to perform like textiles in terms of breathability, conformability, and comfort despite the presence of the electrically conductive elements and electronics. E-textiles are also expected to provide reliable data and signal processing like electronic devices while they are subjected to normal wear and tear under different environmental conditions. The goal of this research was to investigate the electrical integrity of e-textiles while they are subjected to environmental conditions. Different woven samples of electronic-improved outer tactical vest with two narrow conductive traces woven in the warp direction were subjected to range of temperatures and humidity, including extreme conditions. The effects of formation parameters (e-yarn type, number of e-yarns/trace, and weldability), temperature, and humidity on the integrity of the e-textiles were stu...

Fiber-reinforced 3D printing technology offers significant improvement in the mechanical properties of the resulting composites relative to 3D printed (3DP) polymer-based composites. However, 3DP fiber-reinforced composite structures suffer from low fiber content compared to the traditional composite, such as 3D orthogonal woven preforms solidified with vacuum assisted resin transfer molding (VARTM) that impedes their high-performance applications such as in aerospace, automobile, marine and building industries. The present research included fabrication of 3DP fiberglass-reinforced nylon composites, with maximum possible fiber content dictated by the current 3D printing technology at varying fiber orientations (such as 0/0, 0/90, ±45 and 0/45/90/−45) and characterizing their microstructural and performance properties, such as tensile and impact resistance (Drop-weight, Izod and Charpy). Results indicated that fiber orientation with maximum fiber content have tremendous effect on the improvement of the performance of the 3DP composites, even though they inherently contain structural defects in terms of voids resulting in premature failure of the composites. Benchmarking the results with VARTM 3D orthogonal woven (3DOW) composites revealed that 3DP composites had slightly lower tensile strength due to poor matrix infusion and voids between adjacent fiber layers/raster, and delamination due to lack of through-thickness reinforcement, but excellent impact strength (224% more strong) due to favorable effect of structural voids and having a laminated structure developed in layer-by-layer fashion.

Three-dimensional printing (3DP) is at the forefront of the disruptive innovations adding a new dimension in the material fabrication process with numerous design flexibilities. Especially, the ability to reinforce the plastic matrix with nanofiber, microfiber, chopped fiber and continuous fiber has put the technology beyond imagination in terms of multidimensional applications. In this technical paper, fiber and polymer filaments used by the commercial 3D printers to develop fiber-reinforced composites are characterized to discover the unknown manufacturing specifications such as fiber&ndash, polymer distribution and fiber volume fraction that have direct practical implications in determining and tuning composites&rsquo, properties and their applications. Additionally, the capabilities and limitations of 3D printing software to process materials and control print parameters in relation to print quality, structural integrity and properties of printed composites are discussed. The work in this paper aims to present constructive evaluation and criticism of the current technology along with its pros and cons in order to guide prospective users and 3D printing equipment manufacturers on improvements, as well as identify the potential avenues of development of the next generation 3D printed fiber-reinforced composites.

In our previous publications, the response of perfluorinated (PF) graded index (GI) POFs (62.5/750, 62.5/490m) to bending, tensile loading, and cyclic loading was investigated. The results showed that Cytop-1 (62.5/750m) was more appropriate to be used as an optical fiber sensor for automotive seat occupancy sensing relative to Cytop-2 (62.5/490m). In this study, a textile-based optical fiber sensor was designed and the effect of automotive seat covering including face material and foam backing on a sensor's performance was analyzed. The pressure interval under which the proposed POF sensor design could perform well was found to be between 0.18 and 0.21N/cm(2), where PF GI POF (62.5/750m) was used as the POF material. The responses of the sensor in this interval were observed to be accurate and reproducible. The face fabric structure and the thickness of foam backing were not found to be significant factors to change the sensor response. Artificial neural network (ANN) was used for data analysis, and Qwiknet (version 2.23) software was used to develop ANNs. According to the results of Qwiknet, the prediction performances for training and testing data-sets were 75 and 83.33%, respectively.

The goal of this research aimed to develop an accurate and reproducible textile-based optical fiber sensor for automotive seat occupancy. In our previous publication, the response of perfluorinated (PF) graded index (GI) polymer optical fibers (POFs) (62.5/750 and 62.5/490m) to bending and tensile loading was investigated. In this study, the response of the PF GI POFs to cyclic loading was investigated. The repeated loading and unloading the POF sensor would experience due to car vibrations and multiple uses by seat occupants, might cause fatigue failure to the POF sensor. The results showed that the Cytop-1 did not show any permanent deformation up to 500 cycles at strain rates 4 and 60mm/min at a gage length of 76.2mm in its elastic sensitive strain region. The Cytop-2 showed permanent deformation at 3.5% strain after 500 cycles at a gage length of 76.2mm. Thus, the Cytop-1 was found out to be more appropriate to be used as an optical fiber sensor for automotive seat occupancy sensing relative to the Cytop-2. In this study, a theoretical approach of the behavior of PF GI POF to cyclic loading was also provided.

This work aims to find out the gel time that may not cause damage to the physical properties of the polymer optic fiber (POF). Effect of gel time of vinylester resin on signal attenuation of POF was studied. The resin gel time was controlled by mixing different ratios of Methylethylketone peroxide (MEKP), Cobalt Naphthenate-6 %, and Dimethylaniline at 18 °C. OTDR was used to measure backscattering level and signal loss during the resin curing process. Optical imaging was conducted on POF cross section before and after resin treatment to investigate the effect of resin gel time on its physical properties. Results showed that POF signal was affected by resin gel time. Increasing gel time caused drop of the backscattering level of the POF. It was found that 15 minutes gel time had no significant effect on POF signal integrity. Gel time 45 minutes or longer cause severe physical damage to the POF.

Super pressure balloons (SPBs) are used by the National Aeronautics and Space Administration (NASA) for ultra-long duration ballooning (ULDB) missions which carry various scientific explorations to support space and earth sciences research activities. The resistance to photo-degradation of load-bearing braided tendons of SPBs is critical to the success of ULDB missions. Recognizing the critical need to improve UV and visible light (UV–Vis) protective performance of p-phenylene-2, 6-benzobisoxazole (PBO) braids, North Carolina State University and NASA's Balloon Program collaborated to investigate the effectiveness of sheath extrusion method in improving the UV–Vis resistance of tendons. This study included two PBO tendon types – 48,000 (48k) denier tendons and 72,000 (72k) denier tendons. Using a sheath extrusion method, the tendons were covered with UV protective sheath of low-density polyethylene containing two types of UV inhibitors – TiO2 rutile nanoparticles and PolyOne PE White CC®. Bare and sheathe...

Three-dimensional printing (3DP), interchangeably termed as additive manufacturing, is an emerging technology for creating myriad objects with numerous design flexibilities by sequential layering. The research revolving 3DP to develop different high-performance materials is in its young stage and burgeoning exponentially throughout the globe. The widest applications of 3DP technology are found in automobile, aerospace, building, metal and alloy, electronic and biomedical fields. Recently, the opportunity to use fiber as reinforcement in the plastic resin of 3D printed model has contributed significantly to the improvement of mechanical performances of 3D printed composites. In the present review, along with introducing brief history of 3DP, mechanism of embedding different continuous fibers into different plastics and their microstructural and mechanical properties including predicting models have been critically reviewed. Additionally, based on the limitations of current technology future research directions have been defined.

A range of intricate finished seamless shaped garments have been developed with the aim to fit predetermined sizes. The shape is created by using woven tubular fabrics with differential shrinkage in the same garment. The differential shrinkage is obtained by altering the fabric construction parameters at strategic locations along the length of the garment. The construction arameters include different weaves (plain, 2/2 basket, 1/3 twill, 2/2 twill, and crowfoot), weft densities, weft yarn counts, and weft yarns with different shrinkages (cotton, cotton that contains spandex, and cotton/polyester yarns). The weft yarn tension is used as an additional parameter to influence fabric shrinkage. A total of thirty-three woven fabrics are formed to establish the relationship between the construction parameters, weft tension, and shrinkage of the finished woven fabric. The relationship is used to produce a range of intricate garments with inherent shapes and predetermined sizes.

Through the thickness mechanical properties of composites have been improved with the advance of 3D woven preforms incorporating through-thickness reinforcement element compared to 3D woven composites from stack of 2D fabrics. In this study, a generalized geometric model considering non-jammed and jammed constructions of 3D orthogonal woven preforms from spun yarns was developed to predict fiber volume fraction (FVF) of structure constituents, preform thickness, preform areal density, and minimum thread spacing (x-, y-, and z-yarn spacing) to achieve jammed construction in terms of weave factor, number of layers, and constituents’ variables (y- and z-yarn sequence, linear densities, packing factor, and fiber volumetric density). Numerical results are presented to demonstrate the generalized model potential as a design tool to achieve broad range of constituents FVF that controls composite performance.

Silica optical fibres (SOF) are established for the use of communicating digital data and numerous applications including structure health monitoring. However, SOFs exhibit drawbacks such as brittleness, low strain and signal attenuation due to bending. These drawbacks limit the use of SOF as embedded sensors for monitoring composite structures’ internal health. Unlike SOFs, the relatively newly developed polymer optical fibres (POF) do not possess such drawbacks and they are able to monitor the health of fibre-based composite structures. Bending in optical fibres is a major concern since this causes signal attenuation at bending points. Integrating optical fibres into a woven preform requires bending because of the crimping that occurs as a result of weave interlacing. The main objective of this research was to evaluate the effect of the macrobending of optical fibres on signal power integrity. The goal is to design optical fibre sensors embedded in woven preforms that have high sensitivity for monitorin...

Tururi (Manicaria saccifera Gaertn.) is a naturally integrated fibrous structure in a form of sac, which protects the fruits of the Amazon Ubucu palm tree. The goal of this research was to develop and characterize multilayer 3D green composites from Tururi fibrous material and identify applications based on their performance. A total of 12 composite samples were fabricated using Vacuum Assisted Resin Transfer Molding Technique (VARTM) to study the effect of the structural parameters, namely, number of Tururi fibrous layers, fiber orientation, and fiber volume fraction on the tensile and impact behavior of the final composites. The focus of this paper will be on the tensile properties in the sac and cross directions, as for the impact properties, it will be covered in another publication. It was found that a proper stacking sequence, can produce composites from Tururi fibers with quasi-isotropic tensile behavior, and with the proper combination of number of layers, and stretch %, the tensile properties of the produced composite can be optimized.

The automotive industry is a promising area for innovations in the field of polymer optical fiber (POF) sensors as the industry currently uses the POF mostly for data transmissions. Since an optical fiber sensor has a high bandwidth, is small in size, is lightweight, and is immune to electromagnetic interference, it offers higher performance than that of its electrical-based counterparts such as the strain gage, elastomeric bladder, and resistive sensor systems. This enhanced performance makes an optical fiber sensor a suitable material for sensing seat occupancy for improved safety features in automobiles. The overall goal of this research is to develop a textile-based optical fiber sensor for automotive seat occupancy with high accuracy and reproducibility. In this study, the bending and tensile loading responses of POF were investigated, where two perfluorinated (PF) graded index (GI) POFs with two different core/cladding diameters, 62.5/750 and 62.5/490m, were used. The bending loss and the light attenuation against the applied axial stress were measured by a photon counting optical time-domain reflectometer. The critical bending diameters were analyzed: Cytop-1 (62.5/750m)38.10mm, Cytop-2 (62.5/490m)44.45mm. Furthermore, the elastic sensitive strain regions (x), where the stress-induced loss was recoverable, of the POFs at a 76.2mm gage length at a strain rate of 4mm/min were determined: Cytop-1: 3%x3.5%, Cytop-2: 3.1%x3.3%. The Cytop-1 was found to be less sensitive to bending and to have greater elastic sensitive strain range relative to the Cytop-2. In this study, a theoretical approach of the PF GI POF behavior to bending and axial tension was provided. The results demonstrated the feasibility of POFs as optical fiber sensors for automotive seat occupancy sensing.

High-strength fibers are used to produce high-strength-to-weight-ratio materials for applications such as composites, soft and hard body armor, bulletproof vests, and tendons for scientific balloons. Unfortunately, these fibers degrade when they are exposed to ultraviolet–visible (UV–vis) radiation. The objective of this research was to develop systems to improve the UV resistance of such fibers. Composite porous membranes from a polyurethane (PU) matrix loaded with rutile titanium dioxide (TiO2) nanoparticles were developed to protect a braid made of polybenzobisoxazole (PBO) yarns. The PU membranes loaded with TiO2 nanoparticles were prepared by a phase-inversion technique. The effects of the amount of TiO2 nanoparticles on the composite membrane morphological structure and UV–vis light transmission were evaluated. The results show that when the concentration of TiO2 nanoparticles was increased, the porosity of the membrane and its UV–vis blocking effectiveness increased. The UV–vis protection was evaluated by the wrapping of the PBO braid with the composite membranes and exposed to UV–vis radiation. The strength loss of the PBO fiber due to exposure was decreased from 75% for the unprotected sample to 7.8% for the protected sample in the PU loaded with 4% TiO2 nanoparticles. © 2012 Wiley Periodicals, Inc. J. Appl. Polym. Sci., 2013

Nylon and polypropylene surfaces were treated with three different finishes (nonionic, cationic, and anionic) at four different solution concentrations (weight percentage of active finish to solution), 0.025%, 0.05%, 0.075%, and 0.1%. Contact electrification tests showed that charge accumulated on polypropylene decreased as the concentration of nonionic and anionic solutions increased, and charge could be controlled when the concentration reached 0.1%. The same effect was realized when the concentration of the cationic solution was only 0.025%. No contact charging was observed on nylon after treating with any solutions. Rubbing electrification (tribo‐charging) of nylon treated with the nonionic solution showed that charge decreased as the solution concentration increased, and no charge was observed as the solution concentration reached 0.1%. Furthermore, no tribo‐charging of nylon was observed at any level of the cationic or anionic agents applied to the surface.

The effect of relative rubbing speed on the tribo‐electrification between different continuous filament yarns and stainless steel “charging pins” was analysed. A modified linear tester, housed in an environmental room, was used to charge the yarn while transporting at desired speed and input tension. The yarn was rubbed against the charging pin, which was also rotated at different speeds. The yarn surface charge, yarn output tension and charging pin’s vibration were monitored in real time automatically. The results showed that for nylon yarn charge was minimized when the yarn/pin relative speed approached zero, regardless of the absolute rubbing speeds of yarn and pin. It was also found that, at the same relative speed, less charge was generated when a larger pin was used. For finish‐free nylon yarn, the charge was also minimized as the relative speed approaches zero; however, for finish‐free polyester yarn and finish‐free polypropylene yarn, the effect of relative rubbing speed on the electrification was...

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 ...

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 measure...

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 ΔEab, with an average ΔEab of approximately five. © 2009 Wiley Periodicals, Inc. Col Res Appl, 34, 225–232, 2009

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.

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.

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 ...

This paper reports a study aimed at detecting warp breaks in terms of yarn type using a Micro-Electro-Mechanical Systems (MEMS) accelerometer based detection system, which has been described in earlier publications. The MEMS accelerometers were mounted on harness cords of a Jacquard tie. MEMS output acceleration signals were analyzed. The signals were acquired while warp ends were up and at the moment of intentional break with a pair of sharp scissors simulating missing warp ends. The results indicated that MEMS acceleration signals at intentional breaks for continuous filament from standard and high strength fibers could be detected. The break signals of cotton and cotton/polyester spun yarns were undetectable.

We developed a system to align fibres by using electrostatic forces to form fibreweb with desired fibre orientation. The purpose of developing such a system is to investigate an innovative mechanism of forming disc shape fibrewebs with engineered fibre orientation for the industrial fields such as carbon fibre reinforced brake discs and abrasive wheels for metal surface finishing. We provide computer models for simulating the process of transporting fibres in electrostatic field and laying them down to a fibre-collecting surface. The model reveals the effects of electrostatic field properties such as voltage and electrodes geometry on fibre orientation distribution. We also developed visualisation programmes to help display and analyse resultant data. Our experimental results and theoretical simulations are in a good agreement and show that the development of a new generation of non-woven fabrics with engineered fibre orientation distribution is achievable with the correct levels of the independent parame...

A geometric model combined with a colour model to predict the colour contribution of each pre-coloured yarn in terms of colour attributes of each area of a Jacquard pattern was developed. To validate the predicted calculations (colorimetric data), a visual assessment experiment was conducted to evaluate the difference between predicted and the actual colour appearance of the woven pattern. The results from the psychophysical evaluation of the woven samples and their predicted colour values showed high correlation between the predicted and experimental data. Therefore, the model has potential to eliminate subjective evaluations and reduce prototype sample production by automating the process of weave/colour simulation.