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The global composite industry generates large quantities of waste which mostly ends up in landfills due to a lack of established end-use applications for multiple waste streams. The scrap from end-of-life (EoL) includes manufacturing waste such as dry chopped fiber tows, loose fibers, shredded fibers from fabric textile operations, cured/semi-cured prepregs, and fully cured composite structure waste from aircraft, automobiles, wind blades, boats, and pressure vessels. In this work, different composite waste streams were reduced to shredded intermediates, followed by simple blending, and subjected to wet compression molding to produce composite panels. The panels/plaques were tested for mechanical properties (flexure and impact), fiber-matrix wet-out, and property bounds. It was found that wet-compression molding was a viable and scaleable approach to produce recycled panels from EoL composites shredded scrap. Furthermore, full-scale size panels for use in truck bodies and intermodal shipping container flooring were manufactured and their impact resistance was tested using a drop weight impact test. They were tested both for high- and low-velocity load. In the case of high-velocity load, the average impact load was 14,673 N; the average absorbed energy was 101.6 J; the average elastic energy was 11.7 J and the impact resistance was 1065 J/m. In the case of the low-velocity drop weight impact test, it was found that the average impact load was 7877.358 N; the average absorbed energy was 9.718 J; the average elastic energy was 9.14 J, and the impact resistance was 184.1 J/m. The shredded composite was shown to be a candidate material for the manufacture of truck bodies and intermodal containers' flooring panels. Highlights • By using shredded intermediates from different composite waste streams, it is possible to manufacture composite panels. • Wet-compression process is an appropriate technique for manufacturing recycled fiber composite panels. • Regardless of the source of scrap, the mechanical properties of the produced composite panels were improved. • The recycling process technology can be transformed to commercial scale to produce full-size transportation flooring panels. • A product pathway is established in consideration of lower cost and improved recyclability. [ABSTRACT FROM AUTHOR]

In this work, we consider low-cost carbon fiber produced with a textile-grade precursor. The objective of the study is to investigate textile-grade carbon-fiber-reinforced-polypropylene composites (TCF-PP) from compounded pellets for mechanical and thermal characterization. Four sets of pellets with 1%, 5%, 10%, and 15% reinforcement were manufactured using textile-grade carbon fiber (TCF) and polypropylene (PP) by twin-screw compounding. The addition of TCFs through gravimetric feeder directly in the extruder resulted in lower fiber content; however, side feeder has shown good potential. The pellets were further processed in extrusion compression molding to manufacture plaques. An increase in fiber loading has a negligible effect on fiber attrition as fiber length distribution variation between 1% and 15% reinforced pellets was very small. The addition of TCFs in PP showed a significant improvement in mechanical properties. The tensile strength and modulus of the composite were 26% and 161%, respectively, improved by the addition of 10 wt% TCF. Similar results were observed in the flexure test. However, the impact properties were reduced by 25.54% by the addition of 15% TCF. [ABSTRACT FROM AUTHOR]

Carbon fibers are a very vast topic to discuss in a limited space such as this review paper. Nevertheless, we herein attempt to provide a succinct summary of current research in carbon fibers (CF), especially carbon nanotube (CNT) based CFs. A brief introduction to CFs with respect to precursors, characterization techniques, and applications is presented. Following discussion on different commercially used CF precursors, is a description of the latest new precursors being researched. While finding new low-cost precursors has been a focus of recent research, large scale production of CFs from these new materials is not being realized at the present time. CNTs have received a great deal of attention due to their unique structure and properties. So CNTs and CNT-based CFs or carbon yarns (CYs) are discussed. In addition to providing a brief overview of different methods of providing CNTs, physical and electronic properties of CNTs are discussed. The major focus of this review is CNT based composite fibers. Efforts by several researchers have shown that incorporation of CNTs in carbon fibers is a challenging task, and only a small percent could be introduced successfully. Applications of CFs in various sectors such as the airline industry, sporting industries, and automotive industries are discussed. Applications of CNTs, focusing on composite materials, coatings and films, microelectronics, energy applications, and biotechnology are briefly reviewed. Some statistics of world market of CFs as well as future prospects are discussed. [ABSTRACT FROM PUBLISHER]

The selectivity and binding kinetics of a lytic phage as a new bio-recognition element were compared and evaluated. The selectivity was studied by exposing the magnetoelastic (ME) biosensor to individual cultures of Escherichia coli O157:H7 (EO), Listeria monocytogenes (LM), Salmonella Typhimurium (ST), Vibrio parahaemolyticus, Yersinia enterocolitica, and methicillin- resistant Staphylococcus aureus (MRSA). A dose response of the ME biosensor obtained from serially increasing concentrations of MRSA was then compared with those obtained from MRSA in a mixture of other competing bacteria. The number of MRSA bound on the measurement sensor was 12,206 ± 750 cells/sensor, which was significantly greater than the number of other competing bacteria bound on the sensor (P < 0.001). The dose responses of sensors to increasing concentration of MRSA and MRSA in a mixture of other competing bacteria were similar, indicating that the resonant frequency shifts of the ME sensor were dependent on the concentration of MRSA. The binding valency and dissociation constant (cfu/mL) of the lytic phage with MRSA, MRSA + LM, MRSA + LM + EO, and MRSA + LM + EO + ST were calculated as 3.3 ± 0.2 and 62.5 ± 11.0, 3.7 ± 0.2 and 56.2 ± 11.8, 3.4 ± 0.2 and 59.4 ± 10.5, and 3.7 ± 0.2 and 56.0 ± 10.7, respectively. This study demonstrated that lytic phages were able to bind with MRSA specifically and selectively even in the presence of other competing bacteria. [ABSTRACT FROM AUTHOR]