The effect of graphene content on the structure and conductivity of cellulose/graphene composite

The effect of graphene content on the structure and conductivity of an eco-friendly cellulose/ graphene (CG) composite was investigated. Different compositions of graphene content from 0 to 70 wt. % were prepared using the sol-gel method. Ionic liquids 1-butyl-3-methyl-imidazolium chloride was used to disperse graphene between the cellulose. The investigation showed that CG composite with higher graphene composition exhibits higher conductivity. The highest conductivity (2.85×10-4 S cm-1) was observed at 60 wt. % graphene composition. Sample without graphene showed the lowest conductivity of 1.77×10-7 S cm-1, which acts as an insulator. The high conductivity of CG composite can be associated with the X-ray diffraction (XRD) patterns. The XRD patterns of α-cellulose exhibits a decrease in crystallinity at peak 15° and 22° due to the depolymerization in CG composite. At 60 wt. % composition, XRD pattern showed the decrease in intensity at peak 26° indicates that graphene is more dispersed in the cellulose mixture. This is supported by Fourier transform infrared spectrum of CG composite where the absorption peaks of C-O stretching are weakened at wavelength of 1163 and 1032 cm-1, suggested dehydration and rupture of cellulose. The dehydration and rupture of cellulose result in the high conductivity of CG composite. This research is believed to provide an eco-friendly method to produce cellulose/graphene composite which is useful in future applications of energy

Physico-thermal properties of kenaf fiber/high-density polyethylene/maleic anhydride compatibilized composites

Kenaf fiber/high-density polyethylene/maleic anhydride (MA)-compatibilized composites were melt mixed in a twin-screw extruder and molded using injection molding machine. Physicothermal properties of the composites were studied at different percentages of compatibilizer contents using various techniques. The addition of 8% compatibilizer into 8.5 and 17.5 wt% fiber content improved the adhesion and tensile strength by 14.5% and 13.6%, respectively. Compatibilized samples exhibited higher peak load and fracture energy on impact testing compared to the samples without maleic anhydride compatibilizer. The effect of the addition of maleic anhydride compatibilizer on peak load and fracture energy was observed to be at its highest at 8%. Differential scanning calorimetric measurements revealed that the melting enthalpy and degree of crystallinity of composites increased with increasing compatibilizer content up to 8% and then decreased at 12% compatibilizer content. Dynamic mechanical analysis showed that the storage modulus of composites was increased, but the loss modulus and tangent delta were decreased after the addition of compatibilizer. This indicates that compatibilized composites produced have improved toughness and reduced stiffness

Fuzzy risk analysis under influence of non-homogeneous preferences elicitation in fiber industry

Fuzzy risk analysis plays an important role in mitigating the levels of harm of a risk. In real world scenarios, it is a big challenge for risk analysts to make a proper and comprehensive decision when coping with risks that are incomplete, vague and fuzzy. Many established fuzzy risk analysis approaches do not have the flexibility to deal with knowledge in the form of preferences elicitation which lead to incorrect risk decision. The inefficiency is reflected when they consider only risk analyst preferences elicitation that is partially known. Nonetheless, the preferences elicited by the risk analyst are often non-homogeneous in nature such that they can be completely known, completely unknown, partially known and partially unknown. In this case, established fuzzy risk analysis methods are considered as inefficient in handling risk, hence an appropriate fuzzy risk analysis method that can deal with the non-homogeneous nature of risk analyst’s preferences elicitation is worth developing. Therefore, this paper proposes a novel fuzzy risk analysis method that is capable to deal with the non-homogeneous risk analyst’s preferences elicitation based on grey numbers. The proposed method aims at resolving the uncertain interactions between homogeneous and non-homogeneous natures of risk analyst’s preferences elicitation by using a novel consensus reaching approach that involves transformation of grey numbers into grey parametric fuzzy numbers. Later on, a novel fuzzy risk assessment score approach is presented to correctly evaluate and distinguish the levels of harm of the risks faced, such that these evaluations are consistent with preferences elicitation of the risk analyst. A real world risk analysis problem in fiber industry is then carried out to demonstrate the novelty, validity and feasibility of the proposed method