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Quantification of tire tread wear particles in microparticles produced on the road using oleamide as a novel marker
2021
Chae, Eunji | Jung, Uiyeong | Choi, Sung-Seen
In general, tire tread rubber compounds contain oleamide for improvement of manufacturing processibility, mold release characterization, and abrasion resistance. Tire tread wear particles (TWPs) are one of major contributors to microplastic emissions. In this study, a novel analytical method for quantification of TWP in microparticles produced on the road (road dust, MPRs) was developed by employing oleamide as a new marker. MPRs were collected at bus stops in autumn, winter, and summer seasons. MPRs of 38–63, 63–106, 106–212, and 212–500 μm obtained by size separation were employed for the analysis. Rubber components for bus and passenger car tire tread compounds were identified using pyrolysis-gas chromatography/mass spectrometry (Py-GC/MS). Oleamide was extracted from the MPRs with acetone and was identified using GC/MS. The oleamide concentration was analyzed using GC equipped with flame ionization detector (FID). The TWP contents of the MPRs were determined using the oleamide concentrations and the reference compound formulations. In order to reduce the sampling errors, each experiment was carried out five times and the results were averaged. The TWP contents of the MPRs were 1.4–4.7 wt% and were different according to the sampling seasons and places. The TWP contents were increased by increasing the traffic volume and the temperature.
显示更多 [+] 显示较少 [-]Impact of dyes and finishes on the microfibers released on the laundering of cotton knitted fabrics
2021
Zambrano, Marielis C. | Pawlak, Joel J. | Daystar, Jesse | Ankeny, Mary | Venditti, Richard A.
The influence of common textile finishes on cotton fabrics on the generation of microfibers during laundering was assessed. Microfiber release was determined to be in the range of 9000–14,000 particles per gram of cotton fabric. Cotton knitted fabrics treated with softener and durable press generate more microfibers (1.30–1.63 mg/g fabric) during laundering by mass and number than untreated fabric (0.73 mg/g fabric). The fabrics treated with softener generated the longest average microfiber length (0.86 mm), whereas durable press and water repellent treatments produced the shortest average microfiber length (0.62 and 0.63 mm, respectively). In general, the changes in the mechanical properties of the fibers and fabrics due to the finishing treatments are the main factor affecting the microfiber release. The abrasion resistance of the fabrics decreases for durable press treatments and water repellent treatments due to the brittleness in the structure originated by the crosslinking treatment. In the case of the softener treatment, the fabric surface is soft and smooth decreasing the friction coefficient between fibers favoring the fibers loosening from the textile and resulting in a high tendency for fuzz formation and microfiber release. These findings are useful for the textile industry in the design and selection of materials and treatments for the reduction of synthetic or natural microfiber shedding from textiles.
显示更多 [+] 显示较少 [-]Performance evaluation of conventional and hybrid woven fabrics for the development of sustainable personal protective clothing
2020
Memon, Arshad Hussain | Peerzada, Mazhar Hussain | Brohi, Khan Muhammad | Memon, Sheeraz Ahmed | Mangi, Sajjad Ali
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.
显示更多 [+] 显示较少 [-]Impact of substrate material on algal biofilm biomass growth
2019
Venable, Mark E. | Podbielski, Melanie R.
Algae are being grown for wastewater purification and biofuels production. Their growth on a substrate facilitates these uses by allowing facile separation of algae from the water. Here, we compare different materials to determine which would best serve this purpose. A mixed culture of Anabaena and Chlorella was grown on various synthetic and natural fiber fabric substrates in a trough system with recirculating simulated wastewater. Filter materials studied as substrates for algal growth were muslin, olefin, pellon (acrylic), two types of polyester, and two types of nylon. Biomass accumulation on the various filter substrates was recorded at 7, 14, and 28 days. Filters were weighed before and after the growth periods and changes in dry biomass were recorded. Biomass accumulation was significantly affected by the fabric type. Olefin fostered the greatest increase in biomass while nylon and polyester also supported competitive increases in biomass. Pellon showed the smallest biomass increase and muslin decreased in mass due to material disintegration. Other concerns such as abrasion resistance and UV susceptibility are discussed.
显示更多 [+] 显示较少 [-]Influence of particle size on the physico-mechanical and energy properties of briquettes produced with coffee husks
2021
Setter, Carine | Ataíde, Carlos Henrique | Mendes, Rafael Farinassi | de Oliveira, Tiago José Pires
Briquetting is a technology with the potential to convert agricultural wastes into solid biofuels with improved handling, transport, storage, and energy efficiency characteristics. It is important to study the variables related to the briquetting process and the raw material because these parameters can affect the quality of the final product. Thus, the objective of this study was to investigate the influence of particle size on the physico-mechanical and energy properties of briquettes produced with coffee husks. Three particle size fractions were obtained: particles larger than 1.8 mm, in the range of 1.8–1.2 mm, and smaller than 1.2 mm. The coffee husk briquettes were prepared in a densification system at 120 °C and 15 MPa for 15 min. The physical, mechanical, and energy characteristics such as apparent density, volumetric expansion, compressive strength, abrasion resistance, and energy density were determined. A combustibility test was also carried out. The results showed that particle size influenced the apparent density, compressive strength, and energy density of the briquettes. However, there was no significant difference in the volumetric expansion or abrasion resistance of the densified products among the treatments. In general, the briquettes made with particles smaller than 1.2 mm had better physico-mechanical and energy characteristics.
显示更多 [+] 显示较少 [-]Soy proteins as environmentally friendly sizing agents to replace poly(vinyl alcohol)
2013
Chen, Lihong | Reddy, Narendra | Yang, Yiqi
An environmentally friendly and inexpensive substitute to the widely used poly(vinyl alcohol) (PVA) has been developed from soy proteins for textile warp sizing. Textile processing is the major source of industrial water pollution across the world, and sizing and desizing operations account for nearly 30 % of the water consumed in a textile plant. PVA is one of the most common sizing agents used for synthetic fibers and their blends due to PVA's easy water solubility and ability to provide desired sizing performance. However, PVA does not degrade and is a major contributor to pollution in textile effluent treatment plants. Although considerable efforts have been made to replace PVA with biodegradable sizing materials, the performance properties provided by PVA on synthetic fibers and their blends have been unmatched so far. Soy proteins are inexpensive, biodegradable, and have been widely studied for potential use in food packaging, as resins and adhesives. In this research, the potential of using soy proteins as textile sizing agents to replace PVA was studied. Polyester and polyester/cotton rovings, yarns, and fabrics sized with soy protein showed a considerably better improvement in strength and abrasion resistance compared to commercially available PVA-based size. Soy protein size had a 5-day biochemical oxygen demand /chemical oxygen demand ratio of 0.57 compared to 0.01 for PVA indicating that soy protein sizes were easily biodegradable in activated sludge. The total and ammonia nitrogen released from the proteins also did not adversely impact the biodegradability. Good sizing performance and easy biodegradability demonstrate that soy protein-based sizes have potential to replace PVA-based sizes leading to substantial benefits to the textile industry and the environment.
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