Preparation of PLA-based SMS nonwoven composites and its applications in protective apparel

The global COVID-19 pandemic has triggered a huge demand for the protective nonwovens. However, the main raw material of nonwovens comes from petroleum, and the massive consumption of petroleum-based polymers brings great pressure to ecosystem. Therefore, it is significant to develop biodegradable protective barrier products. In this work, a polylactic-based composite (a tri-layer nonwovens composed of spunbond, meltblown and spunbond, SMS) was prepared and applied for protective apparel. The surface morphology and chemical changes of the fibers were characterized and analyzed by scanning electron microscope (SEM), Fourier transform infrared spectroscopy (FTIR) and energy dispersive spectroscopy (EDS). The liquid contact angle and permeability, breathability and moisture permeability, frictional charge and mechanical strength of the samples were evaluated and compared. The samples degradability was also recorded. The results demonstrate that the optimum formula for anti-fouling treatment on SMS is F-30. The treated fabric possesses superior liquid repellency and anti-permeability, with contact angles of water and alcohol at 128° and 115° respectively, while the alcohol repellent grade reaches level 7. The treated sample has less strength loss but exhibits favorable breathability, moisture permeability and anti-static properties, which can meet the requirements of protective apparels. After fluorine resin coating, the composite still provide excellent degradation performance, and the weight loss rate reaches more than 80% after 10 days water degradation. These results provide new insights for the application of PLA-based SMS in biodegradable protective apparel. © 2023 The Textile Institute.

ZnO coated nonwoven polypropylene fabric with antibacterial and antiviral function for medical applications

The present pandemic has highlighted the necessity of infection protection gear as a crucial protective approach, particularly given the fact that severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) readily infects individuals in poorly ventilated environments. Embedding antimicrobial function onto protection gear would have major implications in minimizing pathogen contamination and lowering healthcare associated illness. In this study, non woven polypropylene fabric (NWPP) which is widely used in personal hygiene products and hospital protective gears has been subjected to surface fictionalization with corona treatment. Surface polarity of the treated fabric was studied by use of dyne liquid which showed generation of surface polarization. Subsequently, the resultant surface polarized NWPP were spray coated with zinc oxide (ZnO) antiviral agent. The antiviral agents were rendered to adhere to NWPP by use of polyurethane solution coating on the fabric. The effect of antiviral coatings on NWPP fabric with the use of polyurethane solution as an adhesive were investigated in terms of antiviral activity and anti-bacterial activity against MS2 bacteriophage and Staphylococcus aureus and Klebsiella pneumonia bacteria respectively. Coating of surface polarized NWPP with polyurethene binder reduced the leaching of antiviral coating. More importantly, the fabrics exhibited promising antiviral and anti bacterial activity with 99.90 % reduction in microorganisms after 24 hours of exposure. © 2022 IEEE.

Toxicity testing of nonwovens used for production of respiratory protective equipment.

OBJECTIVES: During the covid-19 pandemic, protective equipment such as respirators and masks were widely used to protect respiratory tract. This disposable protective equipment is usually made from plastic fibre-based nonwoven fabrics. If used masks and respirators are improperly discarded, they pollute the environment by becoming a source of micro and nanoplastics. The aim of the study was to find out how stable the materials of protective equipment are and how released nano and microplastics can affect aquatic and soil organisms. MATERIALS: The input materials used to produce respirators and masks were tested for their thermal stability and resistance to the release of plastic particles into the environment. To determine the thermal stability of the materials, a simultaneous thermal analysis - thermogravimetry (TGA) and differential scanning calorimetry (DSC) were performed. RESULTS: Materials of masks and respirators are stable at temperatures common to temperate climate zone. However, the possible effects of chemical reactions of the materials with the environment were not considered during the measurement. The materials were also subjected to ecotoxicity tests according to European standards. CONCLUSION: While the leachate obtained by shaking the materials in water did not show acute toxicity to the selected aquatic organisms, the material itself had a significant effect on selected soil organisms (springtails).

The Environmental Impacts of Disposable Nonwoven Fabrics during the COVID-19 Pandemic: Case Study on the Francesc de Borja Hospital.

Hospitals generate huge amounts of nonwoven residues daily. This paper focused on studying the evolution of nonwoven waste generated in the Francesc de Borja Hospital, Spain, over the last few years and its relation to the COVID-19 pandemic. The main objective was to identify the most impacting pieces of nonwoven equipment in the hospital and to analyze possible solutions. The carbon footprint of the nonwoven equipment was studied through a life-cycle assessment. The results showed an apparent increase in the carbon footprint in the hospital from 2020. Additionally, due to the higher annual volume, the simple nonwoven gown used primarily for patients had a higher carbon footprint over a year than the more sophisticated surgical gowns. It can be concluded that developing a local circular economy strategy for medical equipment could be the solution to avoid the enormous waste generation and the carbon footprint of nonwoven production.

Amino‐terminated hyperbranched polymer functionalized graphene oxide with in situ trapped silver nanoparticles for high‐performance antibacterial nonwoven fabric

Antibacterial fabric with high thermal stability and mechanical strength is important for personalized protection, especially under the background of coronavirus pandemic (COVID‐19). This paper presents a facile approach toward high‐efficient antibacterial polypropylene spunbonded nonwoven fabrics (SNFs), which are decorated by a composite of graphene oxide embedded with silver nanoparticles (AgNPs/GO) through dip‐coating and in situ reduction effect of pre‐introduced amino‐terminated hyperbranched polymer (HBP‐NH2). Typically, HBP‐NH2 was grafted onto the GO nanosheets, then silver ions were trapped and self‐reduced by the HBP‐NH2 to generate silver nanoparticles decorated GO. The produced AgNPs are uniformly dispersed on the GO with a size of 13 nm. As an antibacterial coating, the Ag/GO composite could tightly wrap the SNFs fibers through the dip‐padding method, capable of enhancing the thermal stability and mechanical property of SNFs. The treated SNFs exhibited excellent antibacterial activities (~99.9%) against both Echerisia coli and Staphylococcus aureus, promising important potential for biomedical and personal protection applications.

Comparison of the performance properties of spunlaid non-woven fabrics used as face mask

Face masks have an effect of preventing the spread of infectious diseases such as coronavirus disease 2019 (COVID-19). With these masks, it is primarily aimed to prevent the environment from being contaminated by the user. However, in the COVID-19 outbreak, many countries made it mandatory to use masks in areas with high human circulation such as marketplaces, shopping malls and hospitals, and then in all areas outside the home. Some tests such as filtration efficiency, microbial load, resistance to body fluids, flammability and breathability are performed to determine the protection potential and wearing comfort of face masks. In this study, we investigated the bacterial filtration efficiency (%), microbial load (cfu/g), breathability (Pa/cm2) and air permeability values of five different face masks obtained by combining polypropylene (PP) nonwoven layers in different weights (accordance with EN 14683:2019 + AC:2019, EN ISO 11737-1:2018 and TS 391 EN ISO 9237 Standards). The surface morphologies of the nonwoven fabrics were characterized by scanning electron microscope (SEM). It was observed that the weight change in spunbond masks (1–4) was directly proportional to bacterial filtration efficiency and differential pressure, and inversely proportional to air permeability. In addition, SEM analysis showed that the average fiber diameter of the meltblown layer was at least 5.80 times smaller than the spunbond layers, and as a result, dramatic differences were also observed in the air permeability and differential pressure values of the Spunbond-Meltblown-Spunbond (SMS) mask (5) compared to spunbond masks.

Amino-terminated hyperbranched polymer functionalized graphene oxide with in situ trapped silver nanoparticles for high-performance antibacterial nonwoven fabric

Antibacterial fabric with high thermal stability and mechanical strength is important for personalized protection, especially under the background of coronavirus pandemic (COVID-19). This paper presents a facile approach toward high-efficient antibacterial polypropylene spunbonded nonwoven fabrics (SNFs), which are decorated by a composite of graphene oxide embedded with silver nanoparticles (AgNPs/GO) through dip-coating and in situ reduction effect of pre-introduced amino-terminated hyperbranched polymer (HBP-NH2). Typically, HBP-NH2 was grafted onto the GO nanosheets, then silver ions were trapped and self-reduced by the HBP-NH2 to generate silver nanoparticles decorated GO. The produced AgNPs are uniformly dispersed on the GO with a size of 13 nm. As an antibacterial coating, the Ag/GO composite could tightly wrap the SNFs fibers through the dip-padding method, capable of enhancing the thermal stability and mechanical property of SNFs. The treated SNFs exhibited excellent antibacterial activities (~99.9%) against both Echerisia coli and Staphylococcus aureus, promising important potential for biomedical and personal protection applications. © 2022 Wiley Periodicals LLC.

Copper Nanoparticle Synthesis on Plasma Treated Poly(lactic) Acid Nonwoven Fabrics

The demand for antibacterial fabric surfaces is increasing day by day. With the covid-19 pandemic situation, there is attention to antibacterial and antiviral nonwoven fabrics which can be used towards the development of personal protective wear. To reduce the environmental pollution caused by disposable and non-biodegradable polymer-made personal protective wear can be replaced by biodegradable polymers like poly(lactic) acid (PLA), which is quite similar to polypropylene, but biodegradable. In this study, the non-thermal plasma treatment method is used to increase the surface reactivity of the PLA nonwoven polymer surface. On the activated nonwoven surface copper nanoparticles are in-situ synthesized by chemical treatments. After 30 minutes of plasma treatment, better copper nanoparticle distribution and higher yield were achieved. Fourier transformed infrared spectroscopy (FTIR) and Scanning Electron Microscopy (SEM) were used to characterize the treated PLA nonwoven fabric surfaces. © 2022 IEEE.

Surface Coating of Needle-Punched Nonwovens with Meltblown Nonwovens to Improve Acoustic Properties

Unlike the term sound insulation, which means reducing the penetration of noise into other areas, sound absorption means reducing the reflection and energy of the sound on the surface. It has become a highly noticed issue in recent years because the noise in our daily life is increasing day by day, and it causes some health and comfort disorders. In many areas, textiles have been used for acoustics control and noise absorption purposes. The purpose of this work is to determine the most effective media for sound absorption performance and its relation to thermal conductivity from needle-punched nonwoven, meltblown nonwoven and hybrid forms in different arrangements of these fabrics. To provide comparable samples, both needle-punched nonwoven and meltblown nonwoven samples were produced from 100% Polypropylene fibres. According to sound absorption tests, the hybrid-structured sample having a composition similar to the needle-punched nonwoven sample placed at the bottom of our study, while the meltblown nonwoven sample placed as a face layer outperformed the rest of the samples in terms of sound absorption and thermal conductivity. ‘Meltblown only’ samples had remarkably higher sound absorption efficiency than most of the samples, while the ‘needle-punched nonwoven only’ sample had the lowest sound absorption efficiency in all frequencies.

Antibacterial Capability of Air Filter Fiber Materials Treated with Triclosan against Indoor Environmental Microbes

Antibacterial filtration materials have been used effectively to control biological pollutants and purify indoor air. This study aimed to assess the antibacterial capability of three fiber filter materials treated with triclosan: glass fiber (GF), non-woven fabric (NF) and chemical fiber (CF). Triclosan was loaded onto the filtration materials by the impregnation method. The triclosan-treated filter materials exhibited antibacterial zones obviously: the average antibacterial bands against E. coli were 11.8 mm (GF), 13.3 mm (NF) and 10.5 mm (CF);against S. albus, they were 25.5 mm (GF), 21.0 mm (NF) and 23.5 mm (CF). The percent reductions of bacteria for the antibacterial air fiber materials treated with triclosan against E. coli were 71.4% (CF) and 62.6% (GF), while the percent reductions against S. albus were 61.3% (NF) and 84.6% (CF). These findings could help to reduce the transmission and threat of epidemic and purify the environment through the use of environmentally friendly antibacterial filter fibers.

Electrospun Polysaccharidic Textiles for Biomedical Applications

Recent developments in electrospinning technology have enabled the commercial-scale production of nonwoven fabrics from synthetic and natural polymers. Since the early 2000s, polysaccharides and their derivatives have been recognized as promising raw materials for electrospinning, and their electrospun textiles have attracted increasing attention for their diverse potential applications. In particular, their biomedical applications have been spotlighted thanks to their “green” aspects, e.g., abundance in nature, biocompatibility, and biodegradability. This review focuses on three main research topics in the biomedical applications of electrospun polysaccharidic textiles: (i) delivery of therapeutic molecules, (ii) tissue engineering, and (iii) wound healing, and discusses recent progress and prospects.

Used disposable face masks are significant sources of microplastics to environment.

The consumption of disposable face masks increases greatly because of the outbreak of the COVID-19 pandemic. Inappropriate disposal of wasted face masks has already caused the pollution of the environment. As made from plastic nonwoven fabrics, disposable face masks could be a potential source of microplastics for the environment. In this study, we evaluated the ability of new and used disposable face masks of different types to release microplastics into the water. The microplastic release capacity of the used masks increased significantly from 183.00 ± 78.42 particles/piece for the new masks to 1246.62 ± 403.50 particles/piece. Most microplastics released from the face masks were medium size transparent polypropylene fibers originated from the nonwoven fabrics. The abrasion and aging during the using of face masks enhanced the releasing of microplastics since the increasing of medium size and blue microplastics. The face masks could also accumulate airborne microplastics during use. Our results indicated that used disposable masks without effective disposal could be a critical source of microplastics in the environment. The efficient allocation of mask resources and the proper disposal of wasted masks are not only beneficial to pandemic control but also to environmental safety.

Roll-to-Roll Production of Spider Silk Nanofiber Nonwoven Meshes Using Centrifugal Electrospinning for Filtration Applications.

Filtration systems used in technical and medical applications require components for fine particle deep filtration to be highly efficient and at the same time air permeable. In high efficiency filters, nonwoven meshes, which show increased performance based on small fiber diameters (e.g., using nanofibers), can be used as fine particle filter layers. Nanofiber nonwoven meshes made by electrospinning of spider silk proteins have been recently shown to exhibit required filter properties. Needle-based electrospinning, however, is limited regarding its productivity and scalability. Centrifugal electrospinning, in contrast, has been shown to allow manufacturing of ultrathin polymer nonwoven meshes in an efficient and scalable manner. Here, continuous roll-to-roll production of nonwoven meshes made of recombinant spider silk proteins is established using centrifugal electrospinning. The produced spider silk nanofiber meshes show high filter efficiency in the case of fine particulate matter below 2.5 µm (PM2.5) and a low pressure drop, resulting in excellent filter quality.