Feasibility study of small core diameter polymeric optical fibers (POF) from poly(methyl methacrylate)

This work describes the fabrication and evaluation of small core diameter Polymeric Optical fibres (POF) prepared from Poly(Methyl Methacrylate) (PMMA). Based on prior study, POF has a very interesting property in terms of short-reach local area networks due to the simpler manufacturing process and inherent immunity to electromagnetic interference and radiation. It can overcome the limiting factors of conventional glass-based optical fibre in terms of cost-effective, flexibility and easy installation. This study focused on introducing effective fabrication method to produce small diameter PMMA POF core using extrusion process. Prior to extrusion, we managed to produce PMMA cores with diameters of 650 μm, 750 μm and 850 μm. Based on the outcome of this study, the drawing tension and extrusion temperature have been identified as major influences on core diameter. The SEM images indicated that dense structure and clean surface whereas DSC and TGA analyses revealed that almost similar glass transition temperature and degradation weight loss in between fabricated PMMA core and industrial polymer optical fibre

Development of composite ceramic/polymeric hollow fibre membrane for water separation at low pressure and ambient temperature

This study proposed an enhanced water purification separation that was carried out at ambient temperature and low-pressure system. ZnO and PVA layers were deposited on the outer surface of Al2O3 hollow fibre membrane, and this composite membrane was used to separate synthetic salt solutions with a concentration of 40,000 ppm. The salt solution was introduced on the outer surface of PVA–ZnO–Al2O3 hollow fibre membrane, and distilled water was flowed through the lumen as draw solution. The PVA–ZnO–Al2O3 hollow fibre membrane showed a water flux of 25.70 kg m2 h−1 with 93.9 NaCl rejection. Al2O3 hollow fibre used in this work possessed asymmetric structure with permeability of 11.6 mD and was identified as a medium that cause a significant pressure drop within the separation system. A considerable pressure drop occurred in the porous region of the ceramic hollow fibre, causing water to vaporise. This phenomenon resulted in water evaporation at the interface between the dense sponge-like region of Al2O3 hollow fibre and PVA–ZnO membrane, thus created a positive flux for enhanced salt separation