AgBr and AgCl nanoparticle doped TEMPO-oxidized microfiber cellulose as a starting material for antimicrobial filter.

Present work covers the state-of-art progress in the advanced nanoarchitecture of organic-inorganic hybrid material; a starting material for the antimicrobial filter. TEMPO-mediated oxidation of microfiber cellulose was carried out to introduce the surface active carboxyl groups. Accordingly, qualitative and quantitative substitution of a functional group was investigated using FTIR, Solid state 13C CP/MAS NMR, and potentiometric titration; the reaction resulted to about 21.06% increase in carboxylate content. Further, the microwave irradiated (600 W) in-situ synthesis of AgBr and AgCl nanocubes were prepared and doped on carboxylated microfiber. The prepared AgBr@TO-MF and AgCl@TO-MF were tested using XRD, XPS, SEM and FTIR. With an average size of AgBr and AgCl nanocubes of around 200 ±â€¯28 nm and 116 ±â€¯10.73 nm. Whereas, AgBr@TO-MF and AgCl@TO-MF shown excellent antimicrobial activity against E. Coli and B. Subtilis, with MIC at around 200 µg/mL and 150 µg/mL, respectively. Fascinatingly, ICP-OES analysis estimated the silver leached was around 0.1 ppm.

Effect of nano-alumina concentration on the mechanical, rheological, barrier and morphological properties of guar gum.

In this work, nano-alumina was utilized as a reinforcing agent for guar gum, with an aim to improve its performance properties; especially, mechanical and barrier i.e. water vapor transmission rate (WVTR). Films were prepared by the process of solution casting. Concentration of nano-alumina was varied as 0, 1, 3, 5 and 7 parts per hundred parts of resin (phr) in guar gum. The prepared pristine and guar gum/alumina nano-composite films were characterized for mechanical, puncture, x-ray diffraction, barrier, rheological and morphological properties. Tensile strength, Young's modulus, puncture strength, viscosity and crystallinity increased; whereas, WVTR, elongation at break (%) and damping factor decreased with increased concentration of nano-alumina in guar gum. However, optimized improvement in the performance properties were determined for 5 phr nano-alumina loaded guar gum polymer matrix, attributed to its better dispersion and interaction into the guar gum polymer chains due to the hydrophilic nature of both the materials. Above 5 phr concentration nano-alumina started forming aggregates, as evident from scanning electron microscopy.