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In this study, a set of polylactic acid (PLA)/polyphenol extracted from date palm fruit (DP) blends were prepared by electrospinning process to be used as cell culture scaffolds for tissue engineering applications. For this purpose, PLA/DP blends with variable composition were dissolved in dichloromethane/dimethylformamide (70:30, v/v) mixture and then electrospun to obtain the fibres. Contact angle measurements, dynamic mechanical analysis, mechanical tensile and scanning electron microscopy (SEM) tools were used to study the physico-mechanical properties of the electrospun scaffolds. The results revealed that scaffolds became more hydrophilic with addition of DP. Increasing the polyphenol concentration caused the tensile strength and Young's modulus to decrease. The SEM graphs indicated a decrease in fibre diameter with increasing DP content. In addition, it was found that both cell proliferation and cell viability were enhanced with increased DP concentration within the scaffolds. The scratch test shows that there is an enhancement in cell migration through the scratch for PLA/DP scaffolds; again, higher DP content resulted better migration. Our results suggest that improved mechanical properties, decreased fibre diameter and enhanced hydrophilicity with addition of DP improved cell migration and cell adhesion for the scaffolds. Overall, these results demonstrate that DP is a potential natural cell-friendly product for tissue engineering applications such as tissue regeneration or wound healing assays.

Mixed oxide ceramic particles were incorporated into Ni-P matrix to synthesize Ni-P-TiO 2 -CeO 2 nanocomposite coatings. In the present study, the effect of concentration of mixed oxide ceramic particles (TiO 2 and CeO 2 ) on structural, surface and electrochemical properties of Ni-P coating is investigated. The coatings were electrodeposited on mild steel substrate and were then characterized using various techniques. The compositional (EDAX) confirms the co-deposition of TiO 2 and CeO 2 ceramic particles into Ni-P matrix. The structural analysis (XRD) indicates that addition of mixed oxide ceramic particles do not have any prominent influence on the structure of Ni-P coatings as parent amorphous structure is preserved even at high concentration of mixed ceramic particles (7.5 g/l). The SEM and AFM analyses indicate that the synthesized coatings are of fine nodular morphology containing uniformly distributed ceramic particles. However, their excessive amount may lead to agglomeration and surface defects. The surface analysis (AFM) also indicates that the surface roughness increases with the increase in amount of TiO 2 and CeO 2 particles. The enhancement in roughness of coatings can be ascribed to the fact the added ceramic particles are hard and remain insoluble in the Ni-P matrix. The potentiodynamic polarization analysis confirms that incorporation of mixed oxide ceramic particles into Ni-P matrix improves its anticorrosion properties. However, their excessive amount may cause decrease in corrosion resistance due to formation of galvanic cells at the defective metal/coating interface.

Membrane separation is gaining great attention in many applications, especially in gas separation. Polysulfone (PSF) is the most widely studied polymeric membrane material for CO2 in its pure or modified state. Ionic liquids supported membrane technology (SILMs) are now widely applied due to their unique properties at room temperatures. In our previous study, we proved the enhanced ability of ionic liquid enhanced PSF for the separation of CO2 from gas streams. In this study, the dielectric measurements (BDS) extending up to 107 Hz for different concentrations of ionic liquid into PSF matrix, are presented. Thermogravimetric analysis measurement (TGA), differential scanning calorimeter (DSC), dynamic mechanical analysis, and the tensile properties of the membranes are studied in order to optimize the efficiency of separating CO2 from CO2/N2 mixture and CO2/CH4. TGA showed that pure PSF is a highly thermostable polymer, of which the 5% weight loss temperature is above 150°C. DSC traces show that the Tg of PSF was 149.5°C and decreases gradually for the composites. This behavior was confirmed with BDS analyses, which also revealed important information about the chain motions dynamics and the fragility index. © 2020 Society of Chemical Industry and John Wiley & Sons, Ltd.