Andre J. West

Plant covers offer a potential non-chemical strategy to reduce insect herbivory and protect plants from weather extremes. The first 3-D spacer fabric constructed as a crop cover in a tunnel field application in previous research from our laboratory increased cabbage vegetative growth 2.93-fold and was resistant to insect penetration. Whether this use will increase fruit production was not studied. Tunnel field studies were conducted here with strawberries since they grow over three seasons (Fall to Spring) and single-layer textiles are used as a cover to protect flowers and fruit from freezing. Covered strawberry plants yielded a 3.56-fold increase in harvestable fruits with the number and weight of fruit significantly higher than in uncovered plants. No differences in vegetative plant biomass were found. The 3-D spacer fabric did not elicit a shade avoidance response. Covering consistently increased temperature, but relative humidity was not affected between the covered and uncovered field plots. The fabric, although porous to air and water, demonstrated absolute aphid exclusion in lab bioassays. In preliminary studies, rhizosphere bacterial colony-forming units did not differ significantly between covered and uncovered plots. On-farm testing is now needed to examine the utility of this new textile for a variety of crop plants in different geographical locations.

Deployed armed forces and the public engaged in outdoor activities are at high risk for mosquito bites and the diseases they transmit. Current mosquito bite-resistant garments prevent blood-feeding with slow-release insecticide formulations. Many people today want to avoid contact with pesticides, especially in their clothing. Insecticide treated clothing also is costly and requires regulatory agency approvals. Using mosquito bite-resistant mathematical textile models and a WholeGarment^® knitting technique, a seamless garment was constructed with military-compliant, no-melt, no-drip flame retardant yarns using an AiryPique knit architecture. The garment was 99.5% bite proof in walk-in cage bioassays with 200 Aedes aegypti host-seeking mosquitoes where the human subjects did not move for 20 min. A standard flame test and a PyroMan^TM flammability study validated the garment’s fire protection, a requirement for military uniforms. The thermal physiological comfort tests (air permeability, wetting time/radius, thermal resistance, evaporative resistance, and sweating thermal manikin test) were similar to current army combat uniforms and appropriate for use in everyday clothing. Bite prevention occurred by physically blocking the insect mouth parts from obtaining a blood meal. The knitting technique is well-suited for mass production of bite-resistant clothing through automation, significantly reducing labor, time, and cost by optimizing “fit on demand” for different body types compared to traditional manufacturing methods. This innovation provides a non-insecticidal, safe, scalable, and efficient solution for protecting individuals against mosquito bites.

The fast fashion industry has significantly increased global textile demand, driving a surge in fiber production. However, only a minimal portion of this fiber comes from recycled sources. In the United States alone, a vast amount of textile waste is generated annually, with over half ending up in landfills, contributing to environmental degradation and global warming. These developments underscore the urgent need for scalable and efficient textile recycling solutions to address both economic and ecological challenges in the fashion industry. Among recycling methods, mechanical recycling stands out for its low cost and simplicity, making it suitable for processing various types of textile waste. This article reviews current knowledge, identifies key research gaps, and provides direction for future studies in mechanical textile recycling. Despite progress, significant challenges remain in improving the quality and efficiency of recycled fiber. This study shows the importance of advancing pretreatment methods and sorting technologies, and highlights understanding regarding shredding, opening processes, and fabric structural properties.

Auxetic metamaterials expand transversely when stretched longitudinally or contract transversely when compressed, resulting in a negative Poisson’s ratio (NPR). Auxetic fabrics are 3D textile metamaterials possessing a unique geometry that can generate an auxetic response with respect to tension. In weft-knitted auxetic fabrics, the NPR property is achieved due to the inherent curling effect of the face and back stitches of the knit loops; they contract in an organized knitting pattern. The traditional method used to evaluate NPR is to measure the lateral fabric deformation during axial tensile testing on a mechanical testing machine, which is time-consuming and inaccurate in measuring uneven deformations. In this study, an efficient method was developed to evaluate the NPR of weft-knitted fabric that can also estimate deformation directionality. The elasticity and extension properties of the weft-knitted fabric can be analyzed immediately following removal from the knitting bed. Five fabrics, all with the same stitch densities (including four auxetic patterns and one single jersey pattern), were designed and produced to validate the proposed method. The use of our estimation method to evaluate the Poisson’s ratio of such fabrics showed higher values compared with the traditional method. In conclusion, the deformation directionality, elasticity, and extensionality were examined. It is anticipated that the proposed method could assist in the innovative development and deployment of auxetic knitted metamaterials.

Mosquito vector-borne diseases such as malaria and dengue pose a major threat to human health. Personal protection from mosquito blood feeding is mostly by treating clothing with insecticides and the use of repellents on clothing and skin. Here, we developed a low-voltage, mosquito-resistant cloth (MRC) that blocked all blood feeding across the textile and was flexible and breathable. The design was based on mosquito head and proboscis morphometrics, the development of a novel 3-D textile with the outer conductive layers insulated from each other with an inner, non-conductive woven mesh, and the use of a DC (direct current; extra-low-voltage) resistor-capacitor. Blockage of blood feeding was measured using host-seeking Aedes aegypti adult female mosquitoes and whether they could blood feed across the MRC and an artificial membrane. Mosquito blood feeding decreased as voltage increased from 0 to 15 volts. Blood feeding inhibition was 97.8% at 10 volts and 100% inhibition at 15 volts, demonstrating proof of concept. Current flow is minimal since conductance only occurs when the mosquito proboscis simultaneously touches the outside layers of the MRC and is then quickly repelled. Our results demonstrated for the first time the use of a biomimetic, mosquito-repelling technology to prevent blood feeding using extra-low energy consumption.

Pesticide-free, 3-D, spacer fabrics (Plant Armor Generation (PA Gen) 1 and 2) were investigated for proof-of-concept as an insect barrier to protect plants and improve plant agronomics for organic farming. The time to 50% penetration (TP₅₀) for tobacco thrips, Frankliniella fusca (Hinds) adults in laboratory Petri dish bioassays was 30 and 175 min for PA Gen 1 and 2, respectively, and 12 min for the control (a commercially available, single layer-crop cover, Proteknet). PA Gen 2 was ≥90% resistant to penetration of unfed caterpillar neonates, Helicoverpa zea (Boddie), while the TP₅₀‘s for Gen 1 and Proteknet were 3.1 and 2.35 h, respectively. In small cage studies, PA Gen 2 covered potted cabbage plants were 100% resistant to penetration by these insects through 10 d after which the study was ended. In small field plot studies for 3 summer months, cabbage plants grew approximately twice as fast when covered versus not covered with Gen 1 and Gen 2 without the need for insecticides or herbicides. This was not observed for the control crop cover. Martindale abrasion tests demonstrated Gen 1 and 2 were at least 6- and 1.8-fold more durable than the control crop cover used. Data are also presented on percentage light, water, air, and water vapor penetration across each textile and operational temperatures and humidity for cabbage plants covered and uncovered in small field plots.

Garments treated with chemical insecticides are commonly used to prevent mosquito bites. Resistance to insecticides, however, is threatening the efficacy of this technology, and people are increasingly concerned about the potential health impacts of wearing insecticide-treated clothing. Here, we report a mathematical model for fabric barriers that resist bites from Aedes aegypti mosquitoes based on textile physical structure and no insecticides. The model was derived from mosquito morphometrics and analysis of mosquito biting behavior. Woven filter fabrics, precision polypropylene plates, and knitted fabrics were used for model validation. Then, based on the model predictions, prototype knitted textiles and garments were developed that prevented mosquito biting, and comfort testing showed the garments to possess superior thermophysiological properties. Our fabrics provided a three-times greater bite resistance than the insecticide-treated cloth. Our predictive model can be used to develop additional textiles in the future for garments that are highly bite resistant to mosquitoes.

Mosquito-borne malaria kills 429,000 people each year with the problem being acute in sub-Saharan Africa. The successes gained with long-lasting pyrethroid-treated bednets are now in jeopardy because of wide-spread, pyrethroid resistance in mosquitoes. Using crowd modeling theory normalized for standard bednet architecture, we were able to design an attract–trap–kill technology for mosquitoes that does not require insecticides. Using three-dimensional polyester knitting and heat fixation, trap funnels were developed with high capture efficacy with no egression under worst-case laboratory conditions. Field testing in Africa in WHO huts with Gen1-3 T (trap)-Nets validated our model, and as predicted, Gen3 had the highest efficacy with a 4.3-fold greater trap–kill rate with no deterrence or repellency compared to Permanet 2.0, the most common bednet in Africa. A T-Net population model was developed based on field data to predict community-level mosquito control compared to a pyrethroid bednet. This model showed the Gen3 non-insecticidal T-Net under field conditions in Africa against pyrethroid resistant mosquitoes was 12.7-fold more efficacious than single chemical, pyrethroid-treated nets.