The impact resistance of layered polymer structures using polyvinyl butyral (PVB) in combination with Kevlar fabric and ultra-high molecular weight polyethylene (UHMWPE) were fabricated and tested. Methods of wet impregnation and hot-press impregnation and consolidation of fabric with PVB and UHMWPE were used to manufacture multilayer constructs. All sandwich constructs were fixed to the surface of ballistic clay and subject to a free drop-weight test with a conical impactor having a small contact area.
View Article and Find Full Text PDFPoly(-phenylene terephthalamide) (PPTA) and ultra-high-molecular-weight polyethylene (UHMWPE) are high-performance polymer materials largely used for body armor applications. Although composite structures from a combination of PPTA and UHMWPE have been created and described in the literature, the manufacture of layered composites from PPTA fabrics and UHMWPE films with UHMWPE film as an adhesive layer has not been reported. Such a new design can provide the obvious advantage of simple manufacturing technology.
View Article and Find Full Text PDFAlternative solid electrolytes are the next key step in advancing lithium batteries with better thermal and chemical stability. A soft solid electrolyte, (Adpn)LiPF (Adpn, adiponitrile), is synthesized and characterized that exhibits high thermal and electrochemical stability and good ionic conductivity, overcoming several limitations of conventional organic and ceramic materials. The surface of the electrolyte possesses a liquid nano-layer of Adpn that links grains for a facile ionic conduction without high pressure/temperature treatments.
View Article and Find Full Text PDFTo tackle growing antibiotic resistance (AR) and hospital-acquired infections (HAIs), novel antimicrobials are warranted that are effective against HAIs and safer for human use. We hypothesize that small 5 nm size positively charged nanoparticles could specifically target bacterial cell wall and adherent fimbriae expression, serving as the next generation antibacterial agent. Herein we show highly positively charged, 5 nm amino-functionalized silver nanoparticles (NH-AgNPs) were bactericidal; highly negatively charged, 45 nm citrate-functionalized AgNPs (Citrate-AgNPs) were nontoxic; and Ag ions were bacteriostatic forming honeycomb-like potentially resistant phenotype, at 10 µg Ag/mL in E.
View Article and Find Full Text PDFPoly(p-phenylene terephthalamide) (PPTA) is a high-performance polymer that has been utilized in a range of applications. Although PPTA fibers are widely used in various composite materials, laminar structures consisting of PPTA and ultra-high-molecular-weight polyethylene (UHMWPE), are less reported. The difficulty in making such composite structures is in part due to the weakness of the interface formed between these two polymers.
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