Graphene oxide scrolls (GOS) are fabricated in high yield from a colloidal suspension of graphene oxide (GO) sheets under shear stress in a vortex fluidic device (VFD) while irradiated with a pulsed laser operating at 1064 nm and 250 mJ. This is in the absence of any other reagents with the structure of the GOS established using powder X-ray diffraction, thermogravimetric analysis, differential scanning calorimetry, X-ray photoelectron spectroscopy, Raman spectroscopy, transmission electron microscopy, atomic force microscopy and scanning electron microscopy.

a Hydrogels have been extensively investigated for use in various applications. Poly acrylic acid (PAA) is a common example, which has been widely used due to its super hydrophilicity properties, biocompatibility and biodegradability characteristics. However its poor mechanical properties, which have been addressed in many research studies, are known as a drawback that limits its applications. So, enhancing PAA mechanical properties using a hyperbranched polymer (HB) is the key question to be addressed in this research.Investigations of the mechanical properties of the PAA-HB hydrogel revealed 130% improvement in the ultimate tensile strength, indicating a two times enhancement compared to that of PAA. Statistical analysis showed that the overall effect of introducing notches (with different depths) on the selected mechanical properties of both PAA and PAA-HB was significant. Mechanical characterization of PAA-HB networks showed that significant improvement in the mechanical properties was achieved as the capability of water uptake increased by 20%. Characterization of the physical properties confirmed that participation of HB may form a PAA based hybrid material with good swelling properties. Those findings are attributed to the supramolecular structure of the HB, which can introduce physical entanglement between the PAA network structure and increase the crystallinity of the final hydrogel as compared to those from the PAA hydrogel.

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In recent years, water swellable rubber composites have been the subject of many scientific and research investigations as well as many industrial programs. Here, we present an updated overview of the developments in the area of water swellable rubber composites with different kinds of fillers, compatibilizers, and cross-linked agents, in terms of their manufacturing methods, synthesis, chemical, physical, and mechanical properties. Several critical issues and suggestions for future work are detailed, underscoring the roles of material scientists and manufacturing engineers in the bright future of this new material through value addition to enhance its usage and fields of application.

Poly-lactic acid (PLA) nanocomposite film was prepared with untreated and silane treated sepiolite through solution casting method. Sepiolite is found to be promising nano inorganic filler used to prepare biodegradable PLA nanocomposite films. The effect of sepiolite loading on the thermal, mechanical, gas permeability, and water vapor permeability (WVP) properties of the films was investigated. X-ray diffraction analysis revealed the crystallinity index and well dispersed sepiolite in PLA/sepiolite thin films. By modifying sepiolite, depending on the nanoclay content, the mechanical properties of films were enhanced. PLA/sepiolite films exhibited improved gas barrier and WVP properties compared to neat PLA. The scanning electron microscope results demonstrated that there is a good interface interaction between sepiolite and PLA. The surface treatment of sepiolite increased the adhesion of the PLA matrix to the sepiolite nanoclay which yielded better mechanical properties of the films as compared to pure PLA. It was observed after 1.5% wt sepiolite, nano-filler tended to agglomerate, therefore mechanical and barrier properties of films decreased.