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Textiles-fibres, yarns and fabrics are omnipresent in our daily lives, with unique mechanical properties that fit the design specifications for the tasks for which they are designed. The development of yarns and fabrics with negative Poisson’s ratio (NPR) is an area of current research interest due to their potential for use in high performance textiles (e.g., military, sports, etc.). The unique braiding technology of interlacement for preparation of braided helically wrapped yarns with NPR effect with later development of auxetic woven fabric made it possible to avoid the slippage of the wrapped component from the core. The applied geometrical configuration and NPR behaviour of the braided helical yarn structure with seven different angles comprising of monofilament elastomeric polyurethane (PU) core with two wrap materials that include multifilament ultra-high molecular weight polyethylene (UHMWPE) and polyethylene terephthalate (PET) fibres were investigated and analysed. The mechanically stable 2D woven textile auxetic fabrics (AF) with various weave patterns such as 2/2 matt and 3/1 twill were developed from the auxetic yarn with PU elastomer core having maximum NPR effect of −1.70 using lower wrapped angle of 9° to study and compare their mechanical responses. The auxetic yarn was used in weft direction and multifilament UHMWPE yarn in warp direction, using semi-automatic loom. Auxeticity of AF was analysed and its various mechanical properties such tensile strength, impact energy absorption, in-plane, and out-of-plane auxeticity, and puncture resistance were studied. Higher energy absorption of 84 Nm for matt fabric was seen compared to twill fabric having an energy of 65 Nm. The puncture resistance capability of matt fabric was better than twill fabric. While twill fabric exhibited better auxetic effect in both in-plane and out-of-plane mode compared to matt fabric. In short, both the twill and matt design AF’s showed unique characteristics which are beneficial in making various protective textiles such as protective helmets, bullet proof shields, cut resistance gloves, blast resistant curtains, and puncture tolerant elastomeric composites.

Geotextile is made of permeable geosynthetic. Geotextile s are formed from synthetic fibers based on polymers that have high mechanical properties in tensile strength, trapezoidal tearing strength, and puncture resistance. Therefore, researchers want to increase the use of Geotextile as an added material in the tensile area of concrete blocks. The test objects used are 9 pieces of 150mm×150mm×600mm beams. The results of the research were that the addition of woven Geotextile s and non-woven Geotextile s on concrete blocks increased, for woven Geotextile s by 21.593% of beams without using Geotextile s and non-woven Geotextile s of 17.058% of beams without using Geotextile s. So the use of Geotextile s on concrete blocks can improve quality because the value of the flexural strength of beams using Geotextile s is greater than beams without using Geotextiles.

Silkworm cocoons illustrate excellent puncture-resistance performance after an insight into their layers while a clear understanding of the correlation between the excellent puncture property and the silk secondary structure is still lacking. Herein, we peeled silkworm cocoon into eight layers, and a combination of examination techniques including scanning electron microscopy, tensile mechanical test, Fourier transform infrared spectroscopy, Raman spectroscopy, and X-ray diffraction were applied to figure out the morphologies (surface and cross-section view), mechanical properties, secondary structure, the content of β-sheet, and crystallinity of each layer's fibroin after degumming. The results indicated that the fifth layer offers a higher level of puncture-resistance than the other layers except for the eighth layer. Additionally, a high content level of β-sheet structure and high crystallinity gives rise to the high puncture strength as for hierarchical silk fibers. In general, the new finding holds great potential inspiration for the design of puncture-resistant composites.

In the work, a kind of composite material with excellent stab/puncture resistance was prepared by resin bonded Kevlar fabric. Water-borne epoxy resin (PAEK), polyacrylamide (APAM), fatty alcohol polyoxyethylene phosphate potassium salt (TFPK) are formulated to form a novel sizing agent that can be used for the sizing Kevlar fabrics. The effects of the sizing agent on the mechanical and stab/puncture resistance are examined. A field emission scanning electron microscopy (SEM), an ultra-depth of field 3d microscope, and a universal testing machine were used to observe and evaluate the morphology of sizing fabrics, the stab/puncture morphology, mechanical properties, and quasi-static stabbing properties, respectively. The test results show that the puncture resistance of the sizing Kevlar fabrics increases first and then decreases with the increase of sizing agent concentration. Compared with non-sizing fabrics, the Kevlar fabrics that are treated with a sizing agent at a concentration of 10 wt% have 524 % higher puncture resistance, 301 % higher stab resistance, and a 6.9-fold increase in the burst strength. Because the fiber bundles in the sizing fabrics are confined due to the resin saturation, the friction among fibers is enhanced and thus better resists an external force and contributes a greater resistance against sharp objects.

The puncture resistant fabrics find use in most of industrial and normal life applications. Traditionally, it is believed that the fabrics woven in plain weave and higher GSM are best solution for ...

For improving dynamic puncture resistance (cone drop test) of the needle-punched nonwoven geotextile fabrics, employing a calendered compound tri-layer sandwich-structure of nonwoven/woven/nonwoven...

Researches for the development of materials with less environmental impact have been more common. Pectin is a natural polysaccharide, presenting in plants and the peel of some fruits. It is atoxic, biocompatible, not expensive and is available as a byproduct of fruit juice industry. In the literature, pectin is commonly found mixed with other polymers. The objective of this work was to study the thermoplasticization with glycerol of high methoxylation pectin by extrusion/thermo-compression for films with industrial application compared to casting films. Properties of water vapor permeablility (1.27–2.47 g mm/KPa h m2), tensile strength (3.44–8.74 MPa), and puncture resistance (43.01–230.75 N/mm) of extrusion/thermo-compression films were evaluated. Color parameters exhibited possibility of samples application in packages that require the consumer to view the product. The results obtained for extruded/thermo-compressed films are similar or superior to those obtained in extruded thermoplasticized starch works. Results showed efficient production of plasticized pectin films with the possibility of industrial application for extrusion/thermo-compression process.

The area of forests continues decreasing while the water/soil loss becomes worse. In these complicated environments, mechanical properties, stability, high modulus and low elongation of geotextiles are required. On a premise of the acquisition of good mechanical properties and the improvement in the deformation and puncture resistance of nonwoven fabric, woven/nonwoven hybrid geotextiles are designed and made with needle punch processing technology in this study. The test results indicate that the mechanical properties of hybrid geotextiles are improved significantly when the areal density of nylon fabrics is increased. In particular, with the areal density of 400 g/m2, hybrid geotextiles exhibit the maximal mechanical properties and puncture resistance. Moreover, the pore fraction of hybrid geotextiles decreases as a result of a rise in the areal density of nylon top/bottom layers. The use of a 3 D mesh fabric as the interlayer provides the needle punched composite geotextiles with the highest tensile resistance, puncture resistance. The composite geotextiles are treated with acid and alkali to simulate the corrosion under natural conditions of stabilized soil. The resultant geotextile has good mechanical properties and acid/alkali degradation resistance. This allows the hybrid geotextiles to stabilize water and soil conservation in complicated conditions.

Aluminium foil (AF) membranes are commonly installed below or above concrete floor slabs to reduce the migration of ground gases into buildings. The membranes typically comprise laminates of low-density polyethylene (LDPE), reinforcement and an aluminium foil layer. The key component providing gas resistance is the aluminium layer. This is typically 0.012 mm thick and is often encapsulated by very thin layers of LDPE. The foil is therefore vulnerable to damage from puncture by narrow sharp objects in the field. Aluminium corrodes in aggressive and moist environments and could therefore be affected by the fresh cement slabs and/or ground moisture. This paper summarises testing completed to assess the puncture and penetration vulnerability of AF membranes in real life scenarios and the observations from an experiment where AF membranes were exposed to various conditions, including alkaline, acidic and direct contact with cement environments. Based on the results, design considerations are provided for AF membrane applications.

Silkworm cocoons display outstanding properties in many aspects, such as thermal protection, biocompatibility and mechanical resistance and so on. In this paper, we focus on the puncture properties without detailed exploration of four types of cocoons (three domesticated cocoon and Eri silkworm). Different sections, end and middle, as well as different directions, puncturing from inner and outer surface, of four types of aforementioned cocoons were systematically analyzed and compared. The results of present research show that the middle section exhibits a relatively greater needle-puncture resistance compare with end section for three B. mori silkworm cocoons. With regard to different puncture directions, from external and internal surface, puncturing from internal surface exhibits a relatively higher needle-puncture load as well as fracture displacement tendencies compared with needle-puncture performance from external surface no matter in middle or end sections. Combining physical parameter assessment, statistical analysis and needle-puncture performance, this research inspires a clear-cut frame to design a composite with high puncture resistance.

Natural fibres like banana and jute are recyclable and biodegradable. The effective utilization of the natural fibre in various applications is gradually increasing due to their environment friendliness. The present work focusses on the dimensional and mechanical properties of banana and jute-blended needle-punched nonwoven fabrics. The needle-punched nonwoven fabrics have been produced with 100% banana, 100% jute and in various blend proportions of banana/jute; 80/20, 60/40 and 40/60, respectively. The dimensional, mechanical properties and pore size of the needle-punched fabrics were tested. The needle-punched fabrics produced with 100% banana and 80/20 banana/jute shows lower air permeability, higher bursting strength and better puncture resistance. The 100% banana fabric also shows lower pore size structure which makes it suitable for geo-textile and agriculture textile applications, where the properties like biodegradability and minimum mechanical strength are critical.

This study explores the influences of needle punching and a shear-thickening fluid (STF) on the stab resistance sandwich-structured composites made of nylon nonwoven and aramid fabrics. Needle punching and different treatments of aramid fabric are conducted to obtain the composites. The effects of needle punching and different treatments of aramid fabrics on the sandwich-structured composites were examined using quasi-static puncture resistance, quasi-static stab resistance, dynamic puncture resistance, and bursting property tests. Results show that needle punching and incorporation of STF positively influence the stab resistance of the composites. This study provides an innovative method to reduce the number of lamination layers and decrease the weight.

Eight different 3D weft-knitted fabrics, consisting of outer, binding, and inner layers, were designed and produced on E20 and E28 circular weft-knitting machines. First, in the outer layer, high molecular weight polyethylene multifilament yarns and steel wire (0.05 mm diameter), twisted with high molecular weight polyethylene multifilament yarns, were used because of their exceptional properties to resist the mechanical risks. Second, in the inner layer, hydrophobic polyester spun yarns were chosen for their suitability to be used in contact with skin. Finally, in the binding layer, synthetic elastic textured polyamide yarns were used to connect the outer and inner layers. Following the standard EN 388, diverse tests were conducted to determine the resistance of the developed 3D weft-knitted fabrics to mechanical risks, i.e., circular blade cut, puncture, abrasion, and tear. The analysis showed that the quantity of steel wire in knitted structure highly influences circular blade cut and abrasion resistance, and moderately influences tear resistance for all the investigated knitted fabrics. While a strong positive correlation between the quantity of steel wire and the puncture force was defined only for 3D fabrics knitted on an E20 circular weft-knitting machine. The findings of the research lead to the conclusion that the designed 3D weft-knitted fabric structures, where the outer layer ensures protection against mechanical risks, while the inner layer is designed for contact with skin, provide complex protection against diverse mechanical risks.

The very thin and lightweight silkworm cocoon has outstanding mechanical properties attributed to its specific composite microstructure. However, the microstructures of the cocoons have not been studied quantitatively, and their anti-puncture performance has not been examined as well. In this study, both domesticated ( Bombyx mori) and wild silkworm cocoons ( Antheraea pernyi, Antheraea mylitta and Samia canningi) were investigated for their microstructures using fractal theory, and their quasi-static puncture resistance was tested and compared. In addition, the effects of cocoon layers and hot-press treatments on the puncture resistance of two cocoon types ( B. mori and A. pernyi) were investigated. The three wild cocoons demonstrated significantly higher fractal dimensions, higher fiber intersectional densities and low porosities, indicating their structures are more optimized. They also displayed better puncture resistance than B. mori. Increased layer numbers could significantly increase the puncture resistance of both cocoon types and A. pernyi showed more remarkable increases. Moreover, the two cocoon types showed optimum puncture resistance after heat treatment with hot-press temperature of 135℃ and pressure of 25 MPa, and A. pernyi showed better puncture resistance after such treatment. Finally, both the maximum puncture force and puncture energy of cocoons displayed a linear increase with the increasing fractal dimensions. The new insights can guide the development of novel protective fiber composites with desirable and predictable anti-puncture performance.

The shape of the needle tip that is currently used in the medical field is a “lancet point,” which is a diagonally cut cylindrical pipe, further cut on both sides. The shape of the needle shank is typically cylindrical. In this paper, tip and shank shapes that differ from the standard shape are experimentally investigated for the purpose of reducing puncture resistance. Microneedles of various cross-sectional shapes, such as polygonal and star-like, were fabricated using stereo laser lithography. Before the needle penetrates the skin, sharp edges at the needle tip may be effective to generate a stress concentration on the skin, inducing a skin fracture. After the needle penetrates the skin, corners in the cross section of the needle shank may effectively reduce the frictional resistance because the contact area between the skin and needle is limited at the corners. A needle insertion experiment was conducted against an artificial skin made of polydimethylsiloxane. The puncture resistance decreased respectively for the circular needle, polygonal needle, and star-shaped needle. For the star-shaped needles, the maximum resistance decreased as the number of corners (N) decreased. For the polygonal needle, the maximum resistance increased as N increased from 3 to 5; however, there was no observable difference for N from 6 to 8. The experimental results show that a triangular star-shaped microneedle is the most effective in reducing the puncture resistance.

This study examines the resistance of three-dimensional (3D) weft-knitted fabrics to mechanical risks to determine the influence of varying percentage contents of high molecular weight polyethylene and basalt on cut, puncture, abrasion, and tear resistance. The three-dimensional weft-knitted fabrics are designed by separating functional layers: the outer (protective) layer contains varying percentage contents of high molecular weight polyethylene and basalt; the inner layer (suitable for contact with the skin) contains polyester; both layers are connected using polyamide. The strength properties of knits in response to mechanical impact were evaluated by performing cut, puncture, abrasion, and tear resistance tests. Basalt was found to improve the cut resistance of knits significantly, even with its content as low as 5% in the outer layer. The knit with the highest high molecular weight polyethylene content in the outer layer demonstrated the best puncture and tear resistance. No correlation was established between the varying percentage contents of high molecular weight polyethylene and basalt and the maximum number of abrasion cycles, as the three-dimensional weft-knitted fabrics showed no noticeable wear. The test results show that the structure of three-dimensional weft-knitted fabric with the outer layer designed to withstand mechanical impact and the inner layer suitable for direct contact with the skin protects against a wide range of mechanical impacts. This applies even when varying percentage contents of high molecular weight polyethylene and basalt are used only in the outer layer.

Nanotechnology is an evolving technology, resulting in significant differences in product behavior. Applications of Nano materials in textiles are constantly growing to improve performance and create unparalleled textile functions for their enormous technical, economic and ecological advantages. It is expected that Nano materials will either enhance existing properties or add new functionalities to textiles such as dirt and water repellent, breathability, UV protection, conductive and anti-static properties, wear and wrinkle resistance or stain resistance or bacteria. Due to advancement in manufacturing of Nano materials, a new developed materials specified in the area of protection has been discovered such as; carbon Nano tube (CNT) and Graphene. CNT has unique mechanical properties, particularly in improving tensile strength, and is one of the strongest known materials used in high-performance nanocomposites due to their unique mechanical properties. And its properties make it the best to reinforce polymers and have a great potential for use in the manufacture of ballistic-resistant materials. Graphene is an allotrope of carbon that exists as a two dimensional sheet. graphene is as a single layer of graphite, where all the carbons exist in a regular hexagonal array, it’s the first two dimensional materials to be available. It is both the lightest known substance and the strongest ever produced. The ability to be solid, strong and flexible at the same time gives this incredible potential for use as a body armor or shielding. Research Subject: Insufficiency of puncture resistant Nano treated fabrics in the Egypt. Objective: Develop and improve puncture resistant factor for cotton fabrics using Nano technology in Egypt. Methodology: Experimental method. Results: The most important results are Emphasize the effective role of Nano technology in puncture resistant in textiles. Through Nano technology and Nano additives a wide range of properties could be added to fabrics. The impact proof treatments of fabrics and material developments have several applications. The mechanical properties of textile fibers can be enhanced by incorporation of nanoparticles in fiber, such properties include increasing puncture resistant. Hematite (Iron III Oxide) Nanoparticles were applied to cotton fabrics using polyurethane cold cure foams as a binder, the treatment enhanced the mechanical properties ‘puncture resistant’, The experiment shows a significant increase in puncture resistance for treated fabrics. Effect of Nano iron on physical properties of cotton fabric lead to Changes in physical properties of Nano iron loaded cotton fabric was evaluated in terms of puncture resistance and compared with the untreated cotton fabric.

In the present work, an attempt has been made to study the effect of structural changes on the sustainable properties of needle punch nonwoven geotextile. There are two important process parameters, which influence the structure significantly. The parameters are punch density and depth of penetration of the needle. This research work is designed by considering the two parameters. Whereas, three-levels of each parameter taken and nine samples prepared by using two-factor three-level full factorial design. The structural analysis was carried out by an image analysis technique. All measured physical and mechanical properties of nonwovens have a strong correlation with the structural parameter. The significant effect noticed on fabric thickness, tensile strength, pore diameter, puncture resistance and impact resistance with the varying considered parameters; punch density and needle depth penetration.

A novel composition of industrial grade bitumen with polymer (polyurethane) additive was synthesized for development of a protective membrane which makes the structure water proof. A series of test were performed on membrane specimens to ascertain their mechanical properties. Blend of Bitumen and polyurethane in form of a membrane or thin film of varying thicknesses were prepared which was then subjected to tensile, elongation, tear, and puncture resistance test in accordance with relevant ASTM codes. Experimental investigations of mechanical properties conducted for development of water proofing membrane have been found to be very helpful in improving the index and structural properties. An optimum mix of both the materials for the membrane development was obtained by analyzing the test values. The study revealed that the tensile curves are significantly influenced by different factors such as strain rate, curing age and thickness of specimens. The presence of polyurethane polymer in the bituminous binder reduced water/moisture penetration and shorten the curing time compared to conventional bitumen. The amalgamation of PU and bitumen exhibits the enhanced property of elongation which is crucial property to counter structural moments and undulations along with tensile strength, tearing load and adhesion to different substrates such as metal, concrete. The end use of the resulting system developed depends on their physicomechanical properties relative to its constituent’s quantities, their interactions and the way product is processed. The main reason for use of this mix proportion is to incorporate advantageous properties of both materials to develop waterproofing. In this paper, testing of mechanical properties of polyurethane based bituminous waterproofing membrane developed has been discussed. These tests investigate the influence of composition on various credential values required in a waterproofing membrane. The research work discussed in the paper provides a scientific reference for the engineering application and design and development of polyurethane based bituminous waterproofing membrane.

A facile route for fabrication of polypropylene separators for lithium-ion batteries with high elongation and strong puncture resistance has been proposed in this work. Polypropylene separators imm...

For the successful and long-term stabilization of natural slopes and new cuttings in unstable soils and rugged rocks, vegetation restoration is extremely important. Combined with dry sowing and water sowing three-dimensional erosion control geopliding can be very effective for this purpose. On the other hand, 3D construction reduces the impact energy of rain drops and the eroding force of water on the slop. Geotextiles, which are otherwise used as a sowing aid, are generally of low power and are therefore effective only on milder cuts or in combination with wire knitting. In the last 15 years, stabilization of slopes with high-grade steel mesh in combination with anchors has proven to be a good solution. The load-bearing nets transmit forces into the anchors via the fastening plates, and due to the high puncture resistance, greater forces can be introduced into the anchors on the slopes. The RUVOLUM® software, developed for this purpose, is used to determine the adequate anchor grid and the combination of the type and diameter of the anchor and the type of support network. In order to extend the scope of the above erosion control geoplants, they are applied in combination with a lightweight high-grade steel support net, which increases their payload to 53 kN / m or a stronger payload net of 150 kN / m. For faster and easier installation, geocomposites are used, which come as a combination of the good sides of a high-grade load-bearing steel mesh and geo-knitting for erosion control. A load of 150 kN / m and a puncture resistance of 180 kN can be transferred to the anchors if a fastening system is used. Here we will show the development and application of this system. Thanks to the system described above, it is now possible, in combination with the soil anchoring system, to effectively provide steep slopes and, depending on location, to restore vegetation.

Graphene-based materials are being developed for a variety of wearable technologies to provide advanced functions that include sensing; temperature regulation; chemical, mechanical, or radiative protection; or energy storage. We hypothesized that graphene films may also offer an additional unanticipated function: mosquito bite protection for light, fiber-based fabrics. Here, we investigate the fundamental interactions between graphene-based films and the globally important mosquito species, Aedes aegypti, through a combination of live mosquito experiments, needle penetration force measurements, and mathematical modeling of mechanical puncture phenomena. The results show that graphene or graphene oxide nanosheet films in the dry state are highly effective at suppressing mosquito biting behavior on live human skin. Surprisingly, behavioral assays indicate that the primary mechanism is not mechanical puncture resistance, but rather interference with host chemosensing. This interference is proposed to be a molecular barrier effect that prevents Aedes from detecting skin-associated molecular attractants trapped beneath the graphene films and thus prevents the initiation of biting behavior. The molecular barrier effect can be circumvented by placing water or human sweat as molecular attractants on the top (external) film surface. In this scenario, pristine graphene films continue to protect through puncture resistance—a mechanical barrier effect—while graphene oxide films absorb the water and convert to mechanically soft hydrogels that become nonprotective.

This study investigated the quasi-static mechanical properties of tomato peels of three cultivars - Hz 5608, Seminis DRI 319 and Seminis HP 849. The peels were produced from infrared (IR) heating with three targeted tomato surface temperatures of 109, 112 and 115 °C at two loading rates which reflected the different heating rates. Peels from conventional lye peeling method using a solution of 10% NaOH at 95 °C were used for comparison. Fresh tomato peels were used as control. A texture analyzer was used to determine the tensile strength to failure, puncture resistance strength, and adhesive strength of peels. It was found that mechanical strengths of tomato peels obtained from both IR and lye peeling processes were significantly (α = 0.05) lower than those of the control. However, the mechanical strengths of tomato peels under IR treatment at the temperatures of 109 and 112 °C were significantly (α = 0.05) higher than those of the peels obtained from lye treatment. The mechanical strength of the peels produced from IR treatment at 115 °C was similar to those produced from lye treatment. The reductions in tensile, puncture and adhesive strengths of peels were up to 88, 87.3 and 74.3%, respectively, for IR heated tomatoes, whereas these were 95.1, 99.3 and 91.3%, respectively, for lye treated tomatoes compared to control. The peels obtained from IR peeling had more integrity than those obtained from lye peeling. Increasing the loading rates of tomatoes during IR heating corresponding to lowered heating rate significantly (α = 0.05) decreased the mechanical strengths of peels due to increased residence time for reaching the targeted temperatures. Tomato cultivars had a significant (α = 0.05) effect on the adhesive strength of peel but not on tensile and puncture resilience strengths. These results provide important information about the changes of mechanical properties of tomato peel under different processes.

The work aimed to evaluate the influence of the type of matrix and the number of reinforcement layers on the puncture of aramid laminates. The samples were examined under laboratory conditions and in ballistic tests. Two series of aramid laminates were produced with different types of the polymer matrix. The epoxy resin (EP) and the styrene-butadiene-styrene (SBS) copolymer were used as the matrix. For comparison, a puncture test was performed for the fabric with the same number of layers in contrast to the laminates. Laboratory tests were carried out using the InstronDynatup 9250 HV drop hammer. The results obtained during the laboratory and ballistic examinations were compared. The samples were fired with a 9 × 19 mm Parabellum projectile. Research into the low-velocity range have shown that SBS laminates absorb impact energy more effectively than epoxy resin ones, but they are similar to fabrics without a polymer matrix. The results of ballistic tests are divergent and indicate that unbound materials are more efficient at absorbing energy than laminates. The reason for this is the different damage mechanisms.

This study investigates the mechanical properties and damage behavior of flexible laminated composites. Needle punching is performed to combine woven Kevlar fabric and two nonwoven low-melting point polyester (LMPET) fabrics into a fabric interlayer. A sheet-extrusion machine is used to bond two thermoplastic polyurethane (TPU) sheets on each side of a fabric interlayer. The tensile strength, peel load, and static puncture resistance of the flexible laminated composites are evaluated, and the influences of needle-punching rates and depths are examined. Test results show that a high needle-punching rate or depth positively affects tensile strength by promoting fiber entanglement. The tensile strength of the 300-15 group reaches 24.70 MPa. Moreover, when the needle-punching depth does not exceed 11 mm, melted LMPET fibers help bond two-phase materials and thus increase the peel loads of the final composites. The 200-11 group has an optimal puncture resistance of 5.86 N. The combination of TPU sheets and woven Kevlar fabrics yields flexible laminated composites with good static puncture resistance. The results of this study can be applied to improve the performance of flexible laminated composites.

In order to deeply explore the fiber characteristics influencing on stab resistance of shear thickening fluid (STF)- impregnated fabrics, two different weaving fabrics, ultra-high molecular weight polyethylene (UHMWPE) fabric and Kevlar fabrics are saturate the various concentrations and particle size of STFs. Result shows that, SiO2/PEG-200 blends demonstrate quick shear-thickening property, and the critical shear rate lowers to 1.2-45 s-1 with higher concentration of 75 nm SiO2. STF concentration and particle size significantly affect spike puncture resistance property, but the knife stab resistance mainly depends on fiber characteristics. Comparatively, STF-UHMWPE composite fabrics exhibit better knife stab resistance but weaker spike puncture resistance than STF-Kevlar fabrics. This study can provide an optimization for structure design of stab resistance armors in the future.

Protective textiles require massive consumption of fibers and fabrics, which is responsible for diverse highstrength fabric waste. Wrongly arranged disposal of textile waste is equivalent to the waste valuable resource while causing environmental pollutions. Aramid selvages are worthwhile recycling and used in this study. They are scattered into Aramid staple fibers and mixed with low melting point polyester (LMPET) fibers to form the Aramid matrices employing the nonwoven process. The matrices are added to different combinations to form Aramid composite matrices and hybrid-fiberreinforced composite boards. The process of shearing, crowding, and friction helps improve the mechanical properties of the composite boards according to the evaluations of conducted tests. With the premise of minimum damage to the fibers, this study uses recycled Aramid waste to produce composite boards that have features of high performance and low production cost. As a test result, the hybrid-fiber-reinforced composite boards with 90 wt% of recycled Aramid fibers have the optimal mechanical property and static puncture resistance.

The ballistic impact mechanism mainly depends on the thickness , dimension , strength , ductility , toughness , and density of the target material. Nanotechnology is an evolving technology, resulting in significant differences in product behavior. Nanomaterials are increasingly used in textiles to increase performance and provide unrivaled textile functionality. It is anticipated that materials such as dirt and waterproofing, breathability , UV protection, conductivity, and antistatic qualities, wear and wrinkle resistance, and stain resistance, and bacteria will be enhanced by nanomaterials or add new features. By incorporating nanoparticles into fibers, the mechanical qualities of textile fibers can be strengthened.

Radial tires have a large market share in the tire market due to their better wear resistance and puncture resistance. However, the complexity of the production process makes impurities and irregular cord spacing defects often appear in the body cord area. In this paper, a method relying on X-ray images to detect impurities and irregular cord spacing defects is proposed. The detection problems of these two types of defects are transformed into calculating cord pixel spacing and background connected domains. Firstly, the tire crown, tire ring, and tire body regions are segmented by a novel semantic segmentation network (SSN). Then the background and the cord are separated by an adaptive binarization method. Finally, the irregular cord spacing defects are detected through the refinement and column statistics. The impurities of tire body are located by the marks of the connected domains. The experimental results of the X-ray images show that this method can meet the positioning requirements of irregular shaped impurities. A idea of setting the threshold column effectively improves the detection speed of irregular cord spacing. In addition, the detection accuracy rates for both types of defects are higher than 90\(\%\), which is helpful for further research on various types of tire defects and the design of an automatic tire defect identification system.

In this study, unlike the previous studies focusing merely on high-performance fabrics (i.e, aramid based Twaron, Kevlar) low velocity impact behaviour of neat and shear thickening fluid (STF) impregnated kevlar, hybrid (Kevlar/Carbon) and carbon fabrics was investigated. In the first stage, STFs with the silica concentrations of 5 wt%, 10 wt%, 15 wt% and 20 wt% were produced separately and the rheological measurement of each individual fluid concentration were carried out. In the second stage of the study, kevlar, hybrid and carbon fabrics were impregnated by STF having a silica content of 20 wt%. Yarn pull-out tests, dynamic puncture tests and quasi-static (QS) puncture tests were carried out on both the neat and impregnated fabrics. The rheological measurements showed that, the resulting silica/PEG400 suspensions exhibit good shear thickening behaviours, however it is not the case for those under a critical silica concentration. The yarn pull out tests revealed that, STF enhances the inter-yarn frictions of all three types of fabric. Correspondingly, STF positively affected the dynamic puncture resistance of kevlar and hybrid fabrics, while it had an adverse effect on carbon fabric. Besides, STF caused increases on the QS puncture resistances of all three fabric types.

Now-a-days with the advent in technological advancements, bituminous compositions modified with polymer are being used for numerous applications such as joint filers, adhesives, protective layers, impregnating agents and roofing material The bitumen exhibits a number of mechanical properties but the conventional bitumen doesn’t congregate many requirements because of its drawback of high susceptibility to temperature. Hence from a product design point of view; the most preferred form is modified bitumen. With this aim, a composition in the form of waterproofing product has been developed by modifying bitumen with polyurethane. Polyurethane because of its attractive morphology and wide range of advantageous mechanical properties is a highly promising material having the ability to alter its microstructure to suite niche applications. The developed matrix incorporates the basic useful properties of bitumen along with excellent properties of polyurethane. This modification will maximize the efficiency of product developed in different scenarios making it a resourceful product in terms of waterproofing, insulation properties and enhanced durability. This paper highlights the experimental investigations of physico–mechanical properties of the matrix developed in the form of membrane of varying thickness made from different ratios using different grades of polyurethane and bitumen. Different ratios, grades and thickness of material have been used in trail mixes to attain optimized matrix for the product. The properties such as tensile, elongation, tear, shore hardness, puncture resistance, etc. of membrane developed of various matrixes are examined with relevant ASTM codes. The research work presented here provides an experimental implication for design; development and application of membrane developed for use in engineering purpose.

Since their introduction as barrier materials in waste containment systems in the USA in 1986 and in transportation related waterproofing systems in Germany at about the same time, geosynthetic clay liners (GCLs) have been installed in a variety of applications. Perhaps the major applications have been as leachate containment barriers beneath landfills and surface impoundments, and as infiltration water barriers in landfill covers. When one considers that the traditional barrier material in these applications is a natural clay mineral sealing layer or compacted clay liner (CCL), it is only logical that the two materials should be compared and contrasted to one another in such a way so as to assess technical equivalency. This paper provides a suggested methodology for providing such an assessment. It is based primarily on technical issues and results in a framework that can possibly be used for assessment of both landfill liner and cover barrier materials. It should be possible to use the same methodology for other than landfill applications where a choice is being considered for substituting a GCL for a CCL. In this assessment it is seen that except for issues of puncture resistance and product thinning due to abutting objects and uneven subgrades (both of which can be avoided by proper design and CQC/CQA procedures), GCLs can often be used on an equivalent basis as CCLs. However, site specific conditions like long term slope stability may provide unique situations calling for specific products or alternate designs. Needed to further this assessment of GCLs to CCLs is a continued dialogue with respect to technical issues, close monitoring of GCL installations, and involvement of regulatory agencies in the decision making process.

Ensuring material performance reliability and lifetime is crucial for practical operations. Small cracks on the material surface are often detrimental to its safe operation. This study describes the development of a hydrogen bond-rich puncture-resistant polyurethane elastomer with supertoughness. The as-prepared polyurethane transparent films feature high tensile break strength (57.4 MPa) and great toughness (228 MJ m-3). Additionally, a facile, low-cost, crack self-diagnostic approach through photoluminescence using a small luminous pen is reported. The materials efficiently achieved self-healing at 90 °C after the crack formation. The change of fluorescence intensity on the crack can be used to track the self-healing process. Therefore, this work provides a guideline for the material design of supertough, puncture-resistant, transparent, and healable elastomers and a crack self-diagnosis and healing approach.

The effect of impact loading at the transfer point is often manifested by mechanical damage to a conveyor belt. To describe the phenomena related to the conveyor belt damage caused by the impact of the material, it is important to monitor the amount of the absorbed impact energy. Therefore, the focus of the present article is on the identification of the effect of the conveyor belt’s structure (textile or steel conveyor belt carcass), as well as the strength, the material’s drop height and the drop weight on the relative amount of impact energy absorbed by a conveyor belt. The result of the article is determining the capabilities of different conveyer belts through the monitoring and the identification of the relationship between the relative amount of the absorbed energy and the selected parameters.

This study examines the performance level of hybrid woven protective clothing (HWPC), manufactured from Kevlar® (K) and Ramie (R) yarns. The weave structures (plain, twill 1/3) and variables fiber ratios were used to produce HWPC. The performance level of HWPC was measured according to EN 388:2016. We came to the conclusion that blade cut resistance of plain and twill structure sustained protection level up to increase of KR 80:20 and KR 70:30, respectively; puncture resistance of K100% and HWPC remained in the same level of protection for plain and twill weaves; Abrasion resistance of K100% and HWPC of plain and twill weaves samples presented abrasive performance of same protection level, but the average number of cycles sustained for twill weave samples was slightly higher than plain weave. However, comparing the plain and twill weaves sample for tear resistance, twill weave samples have higher tear resistance than plain weave. A gray relational analysis and Taguchi method was performed to optimize the performance of two structures with variable fiber ratios. It was established that the article produced with K&R yarns with KR 80:20 ratio and twill weave presented the best performance against all test runs. The main objective of this study is to reduce plastic pollution by reducing the amount of synthetic fiber proportion in personal protective clothing and thereby reducing the dependence on nonrenewable sources for synthetic fiber. The 41 g/m2 reduction of Kevlar® fiber has been made in a conventional PC with ramie fiber, without compromising the protection level. This will enhance the sustainability of HWPC.

High-performance yarns are widely used to produce protective fabrics, including stab-resistant materials. The most common approach to studying the mechanism of puncture prevention is to use simulation to assist analysis. However, the anisotropy of the yarn is often overlooked during simulation owing to various factors. In fact, there is a marked difference between the axial and radial properties of a yarn. This may lead to large errors in research. In the present study, a composite material with a grid structure for puncture analysis was designed to investigate the influence of yarn anisotropy on the accuracy of simulation results. The present study combined an actual experiment with a simulation. In the actual experiment, Kevlar yarn/epoxy resin was used to prepare a mesh composite with a spacing of 1 mm. In the simulation, a 1:1 simulation model of composite material was established using finite element software. A simulated puncture experiment was conducted based on the actual experimental conditions and material parameters. After considering yarn anisotropy, the simulation results were closer to the actual experimental results. The simulation revealed that the main failure modes of the mesh material were the fracture of the resin and the bending deformation of the yarns at the junctions, while the surrounding areas were almost unaffected.

This study aims to investigate the mechanical properties, far-infrared (FIR) emissivity, and limiting oxygen index (LOI) of FIR ray/low-melting-point (LM) nonwoven fabrics, flame retardant (FR)/LM ...

Auxetic materials expand in at least one dimension, when stretched longitudinally i.e. they have negative Poisson’s ratio. Development of 2D woven auxetic fabrics (AF) is a new approach to develop mechanically stable auxetic textile structures. However, the mechanical response of such emerging structure is still not studied in detail yet, therefore different mechanical properties of 2D woven AF are compared with conventional non-auxetic fabric (NAF). AF was developed by orienting yarns in auxetic honey-comb (AHC) geometry and auxeticity is induced due to such orientation of yarns. AF was developed using conventional (non-auxetic) materials; cotton yarn and elastane cotton yarn in warp and weft dimension respectively, using air jet loom. Structure and auxeticity of AF were analyzed using a digital microscope and its different mechanical properties (tensile strength, tear strength, bursting strength, cut resistance, and puncture resistance) were studied. AF showed superior mechanical properties with a lower initial modulus, which is beneficial for different protective textiles applications like cut resistance gloves, blast resistant curtains, and puncture tolerant elastomeric composites.

This paper focuses on the semi-blunt puncture behavior of woven fabrics via finite element analysis (FEA) approaches. In these finite element (FE) models, main structure parameters, such as weave structure, warp density as well as friction coefficient, are systematically considered and calculated via FEA. These microstructure geometrical models are builtup with full consideration of interaction between warp and weft yarns. The theoretical results show that plain woven fabric has better puncture resistance compared with 2/1 twill and 5-harness satin fabrics. With the increase of warp density and friction coefficient, the puncture property of woven fabric will be dramatically improved. Finally, an energy consumption method is adopted to analyze the puncture damage process of woven fabric. The simulation results will benefit for the optimum design of woven fabric with excellent puncture performance.

Natural rubber (NR) latex gloves are widely used as a very important barrier for healthcare workers. However, they can still be perforated easily by sharp devices and instruments. The aim of this study was to investigate the effect of the addition of graphene oxide (GO) to low-ammonia NR latex on its puncture resistance, mechanical properties and thermal stability. GO was synthesized using modified Hummers’ reaction. The produced GO was mixed into the NR latex solution at various doses (0.01-1.0 wt. %), followed by a coagulant dipping process using ceramic plates to produce film samples. Puncture resistance was enhanced by 12% with 1.0 wt. % GO/NR. Also, the incorporation of GO improved the stress at 300% and 500%, the modulus at 300% and 500% and the tear strength of low-ammonia NR latex films.

Stab and puncture resistant body armor is widely used by the law enforcement personnel, security and military in many countries. The primary requirement for the armor is to provide protection against various weapons used in an attack. Comfort properties are given increased importance in many countries and considered the second most important requirement. In this research Kevlar was blended with wool and wool–nylon. The resultant fabrics were coated with silica and their stab and puncture resistance in quasistatic conditions was examined using the universal tensile tester. It was hypothesized that the application of coating will generate higher friction to restrict the lateral movement of yarns, and thus present a higher number of yarns for direct resistance to impact during the attack and dissipating the impact energy, whereas the use of wool and nylon will provide the required ergonomics of wearability and stretch. It was observed that the application of the silica coating helped in improving the resistance to the stab and punctures using weapons such as knife (P1, as specified in NIJ 0115.00), ball and pointed impactors. In the quasistatic tests, the highest value of the maximum resistant force was recorded when the ball was used and the lowest was observed for the knife. Furthermore, the application of coating helped in absorbing impact energy. However, the fabric stiffness increased due to the coating, which will negatively impact the ergonomics and wearability.

For structures that carry dynamic loads, the requirements are imposed for safety reasons. The requirements apply to both materials and construction. This requires searching for optimal calculation methods, including geometric and physical nonlinearity, which are results from the construction of the structure. An example is various ballistic structures (ballistic shields), which are hit by bullets in which huge energy is accumulated. In this case, the hitting in the shield with a bullet can be considered as a load due to mass impact. Loads at high strain rates are described by various mathematical models. The mathematical model is complex because a large number of "coefficients" is required, moreover, the obtained test results are not always repeatable. The paper presents the results of shooting multilayer plates with composite materials with 7.62 mm caliber bullets. The shield consisted of three layers, the outer layers were steel or aluminum, the inner layer was natural or modified wood. The samples had the shape of a shield and were 50 mm in diameter and of different thickness. The results of the research allowed to assess the impact of wood modification on its puncture resistance.

In this research, eight different 3D weft-knitted fabrics were developed and evaluated. 3D fabrics have been knitted on circular weft-knitting machines with two different gauges: 20E gauge and 28E gauge. Three different raw materials were used for the fabric’s production: high molecular mass polyethylene (HPPE) yarn and 0.05 mm diameter steel wire in the outer layers (for the front and reverse) and polyamide yarn in the binding layer. The experiments were conducted on the developed 3D knitted fabrics to determine the fabric’s resistance to mechanical risks such as circular blade cut, puncture, abrasion, and also to evaluate the comfort parameter, such as air permeability. It was defined that 3D weft-knitted fabrics best results on tests: circular blade cut, puncture and abrasion resistant were achieved using HPPE yarn twisted with steel wire, higher mass per unit area with more significant amount of steel wire. According to the standard EN 388:2003, three samples of developed 3D weft-knitted fabrics had the highest 5th blade cut and the highest (4th) abrasion resistance level. All of them had the highest (4th) level of puncture resistance. 3D fabrics knitted on a circular weft-knitting machine of gauge 28E ensured 1.3–2.1 times greater blade cut and 4.9–12.1 times greater abrasion resistance result, than fabrics knitted on gauge 20E, due to a higher stitch density, higher mass per unit area, density and fabric’s thickness. But on the other hand, these parameters lowered air permeability by 20.2–43.0%.

High-modulus PET filaments and thermal bonding are used to reinforce the puncture resistance stability of the insole composite. This study aims to discuss the influences of the amount of low-melting-point polyester fibers (LMPET) and needle densities (ND) on tensile, bursting, and quasi-static puncture resistance properties. Besides, significance of LMPET amount and ND on puncture resistance against flat-head (A), spherical-head (B), and pointed-head (C) probes are in particular investigated to simulate the diversified application environments for insoles. Research result shows that, LMPET amount significantly affects the static puncture resistance against three probes; ND only significantly influences the puncture resistance against Probe A and C. Thermal bonding significantly improves the puncture strength against Probe B with various LMPET amounts of insoles, but evidently increases the puncture resistance against Probe A and C when being punched at various ND. The amount of LMPET fibers has a positive influence on the puncture strength of insoles, and 70 wt% of LMPET provide the average static puncture resistance up to 342.6 N. The high-modulus resultant insoles have advantages of flexibility, ease of process, and bendability with a higher and more stabilized puncture resistances.

Nonwoven fabrics were used as reinforcement to laminated composites to improve the mechanical properties and damage behaviors. The needle-punched Kevlar/LMPET nonwoven interlayer and two TPU covers were combined via thermal bonding to form the laminated composites. Tensile strength, peel load, and static puncture resistance of the laminated composites were evaluated in terms of needle punching rate and depth of the nonwoven interlayer. Results showed that tensile strength and static puncture resistance depended on the needle punching depth, primarily on the tangled fiber points. The peel load was dependent on the needle punching rate, especially on the resulting melted LMPET fibers. The laminated composites exhibited desirable tensile properties, peel load, and static puncture resistance.

Puncture resistance has become one of the most requested safety features, not only for protective garments such as stab vests, but also for safety shoes and gloves. Currently, this characteristic is highly demanded in the tyre industry. Conventional protective solutions, such as metallic plates and composite inserts prove to be either bulky or ineffective. The main objective of this work is the design and validation of a novel insert resistant to puncture. This composite insert consisted of a sandwich material with shear-thickening fluid interposed as the core. The dilatancy (shear-thickening) is time-independent rheological behaviour exhibited by some non-Newtonian fluids. These fluids manifest a surge in the apparent viscosity with an increase in the shear rate. In the first part of this work, a comparison between the rheological performance of different shear-thickening fluids (STFs) based on nanosilica dispersed in glycols is presented. This analysis attempts to investigate the combinations of fillers and carriers with the highest energy-absorbing capabilities among various glycol-based colloidal STFs. In the second part, the influence of the composition of the STF on its rheological properties is analyzed statistically. Finally, the puncture resistance of a composite system obtained by encapsulating the previously manufactured shear-thickening fluids in a polymeric shell is analyzed by means of a high-speed puncture test. This test was performed on the mockup of a tyre tread containing the best performing STF. The results showed that the use of the STF core increased the resistance to puncture by 20% as compared to the same volume of tyre tread material. Furthermore, the STF hermetically sealed the pierced sample, even when the tyre mockup was inflated at high internal pressure.