7 research outputs found
Electrospun Polystyrene/LDH Fibrous Membranes for the Removal of Cd2+ Ions
Layered double hydroxides (LDHs) have been extensively studied for a broad range of applications because of their ease of synthesis and chemical modifications. The chemical and crystal structure of LDH provides opportunities of combination with polymers forming nanocomposites. In the current study, MgAl-LDH particulates have been incorporated into micro- and nanofibers of polystyrene (PS) using an electrospinning processing technique of their respective homogeneous solutions. The effect of the varying proportions of LDH and PS on the structure, morphology, and thermal properties of the fabricated LDH-PS fibrous membranes has been investigated. The potential application of the optimally fabricated LDH-PS fibrous membranes in the removal of Cd2+ ions from aqueous media has been evaluated as well. Results showed the possibility of loading the PS fibrous membranes with up to 60âwt% of LDH particulates, which in turn modified the thermal stability and integrity of the produced fibrous membranes. Due to the high hydrophobicity of the PS fibrous matrix, no changes in the crystal structure of the LDH inclusions were observed. Both as-prepared LDH particulates and optimally prepared LDH-PS fibrous membranes showed a high potential for the removal of Cd2+ ions from aqueous media. This is attributed to a cation-exchange mechanism involving the adsorption of Cd2+ ions from a solution with the preferential leakage of Al3+ ions from the crystal structure of LDH
Polyethylene and Polyvinyl Chloride-Blended Polystyrene Nanofibrous Sorbents and Their Application in the Removal of Various Oil Spills
Polymers provide a wide range of properties, and these properties can be greatly enhanced and modified through polymer blending. Polymer blending combines the properties and advantages of their original polymers. This paper showcases hydrophobic polymers prepared through polymer blending; these blends are characterized and evaluated for their efficiency in the removal of crude oil spills from aqueous media. The application of these blends holds a great deal of importance in preserving the environment and the recovery of lost oil in spills. The blends are produced using polystyrene (PS) as the matrix polymer and individually blending poly(vinyl chloride) (PVC) and polyethylene (PE) with the PS consisting of proportions of 5â20âwt.% each. The blends are then electrospun into bead-free microfibers with interconnected porosities as shown by their respective scanned electron micrographs. All fibrous sorbents showed a high affinity towards the removal of crude oil, motor oil, and diesel spills. The highly viscous motor spill showed a different pattern of sorption onto fibers than that of crude oil and diesel spills. Upon comparing all the studied electrospun fibers to commercially available polypropylene fibrous sorbents, results show that the sorption efficiency of the electrospun fibers is superior. Most notably, both PS-PE5 and PS-PVC5 fibers showed to be highly more effective than commercially available polypropylene (PP) sorbents towards all types of oil spills
Ultrasensitive and low temperature gas sensor based on electrospun organic-inorganic nanofibers
Organic-inorganic hybrid material is one of the most promising materials for high performance gas sensors due to its improved properties like high sensitivity, selectivity, fast response time, flexibility and low power consumption. This work presents ultrasensitive, selective and low operating temperature H2S gas sensor. It is based on metal-oxide nanoparticles (NPs) embedded in organic semiconductor polymeric nanofibrous (NFs) membrane containing an ionic liquid (IL). In this context, high surface area Tungsten(VI) oxide- Polyvinyl alcohol (WO3-PVA) nanofibrous composite sensor material with average diameter of 130âŻÂ±âŻ20âŻnm were synthesized with controlled morphology and interconnectivity through an electrospinning technique. The obtained WO3 NPs-containing PVA nanofibrous sensing material was evaluated for its ability as a potential sensor for H2S gas at different operating temperatures and gas concentrations. Results demonstrated that the fabricated sensor is ultrasensitive and selective for H2S gas and exhibit an excellent reproducibility, and long-term stability. Furthermore, the sensor showed adequate response in a humid environment. It was also shown that nanofibers' membrane porosity and thickness control the sensing performance. The optimum operating temperature of 40°C with a detection threshold as low as 100âŻppb with a response time of 16.37âŻÂ±âŻ1.42âŻs were achieved. This combined high sensitivity, fast response time and low operating temperature (low-power consumption) provides clear evidence of the sensor's potential to outperform existing devices, which could pave the way for a commercial exploitation