Advanced Materials Research Vols. 634-638

Abstract: Heat conductive materials, which widely used in the field like electronic information, electrical engineering and aerospace, are required high thermal conductivity, excellent electrical insulation, corrosive resistance, chemical stability and so on. In this paper, metal/unsaturated polyester (UP) composite is prepared to use as heat conductive material. Capacity of composite thermal transmission is analyzed by software ANSYS and experiment. The results show that the capacity of composite thermal transmission increases with increasing metal wire diameter and metal thermal conductivity. Average error between simulation and experimental data is 6.08%.

Abstract: Polymer electrolyte membrane fuel cell (PEFMC) or also known as proton exchange membrane fuel cell is a chemical conversion device that converts hydrogen and oxygen into electrical energy, heat, and water. One of the most important components of PEMFC is bipolar plate, in which it allows for electrons to flow from the anode to the cathode. The objective of this study was to analyze the effect of the addition of multi walled carbon nanotubes (MWCNT) to increase the mechanical and electrical properties of bipolar plate carbon polymer composite. We utilized graphite waste product from electric arc smelting as reinforcementand carbon black made from coconut husk by pyrolysis process as a filler. Bipolar plates were made by compression moulding method at a pressure of 55 MPa and a temperature of 100 o C for 4 hours. Characterization in this study includes density testing, porosity testing, flexural testing, electrical conductivity testing, and observation of the flexural fracture morphology using FESEM. Based on this study, it showed that the addition of 5 %wt MWCNT yielded optimal properties of the bipolar plate (the density was 1.51 g/cm3, the value of porosity was 1.94 %, the flexural strength was 63.31 MPa, and the electrical conductivity was 2.30 S/cm). In conclusion, adding MWCNT as reinforcement in PEMC bipolar plates could reduce the density and the porosity. Thus, it could improve the electrical conductivity and flexural strength of the bipolar plate carbon polymer composites.

Abstract: A novel poly (p-ethylstyrene-acrylamide-propenohydroxamic acid) was synthesized. Copolymerization of acrylamide and p-ethylstyrene was carried out at 30°C in a microemulsion system, in which AM aqueous solution was the continue phase and p-ethylstyrene was the dispersed phase using ST-80 as surfactants respectively. Polymers of hydroxamic functions were prepared with hydroxylamine sulfate at temperatures from 60 °C-85°C and pH=10. The molecular weights were measured through the viscose method and the copolymers were characterized by FT-IR, UV and DSC. The effect of the polymer structure on the process of red mud setting was investigated. The results show that the optimal experimental condition is the hydroxamic acid flocculants contains 10.5% p-ethylphenylethylene and the molecular weight of synthesized product is 11×106; The polymer provides dramatically lower overflow solids at higher mud settling rates than hydroxamic acid flocculant.

Abstract: Cellulose acetate (CA), a hydrophilic membrane material, was selected to prepare ultrafiltration membrane for the aim of achieving high-performance membranes with respect to flux and rejection characteristics. In order to prepare membranes with improved properties, blending of cellulose acetates with different degrees of substititution(DS) has been attempted. In this study, polymeric blend ultrafiltration membranes based on cellulose acetate with different DS were prepared by phase inversion technique. Scanning electron microscopy (SEM), atomic force microscopy (AFM), and contact angle are used to understand the influence of DS on the properties of modified membranes. The blend membranes prepared were subjected to the separation of egg albumin (EA). The separation and permeate flux efficiencies of the blend membranes were discussed.

Abstract: Cellulose nanocomposite is one of the most fascinating materials with broad applications. In this work, cellulose-magnetite nanocomposite has been prepared by dispersion of magnetite nanoparticles in a homogenous ionic liquid solution of grafted cellulose. Bagasse cellulose was first grafted with polymethacrylic acid in 1-butyl-3-methylimidazolium, and then fabricated with Fe3O4 nanoparticles during the homogeneous media. The obtained nanocomposite contained high content of iron due to the clelation of the grafted cellulose and Fe3O4 nanoparticles. It also exhibited superparamagnetic behavior with 8.606 emu/g saturation magnetizations. The cellulose-magnetite nanocomposite will be potential for the development of functional cellulose and protective materials for electromagnet radiation or microwaves.

Abstract: The effects of voids on the residual bending strength after impact of CFRP laminates were discussed in this paper. Impact tests on the CFRP laminates with two porosity levels were conducted at five impact energy levels of 3J, 6J, 9J, 12J and 15J at the room temperature. The bending strength and the bending modulus of non-impacted specimens decreased 0.67% and 0.086% with the porosity increasing from 0.33% to 0.71%. Compared to non-impact specimens, the residual bending strength after impact (BAI) and bending modulus after impact significantly decrease with increasing impact energy. The void contents had the negative effects on the BAI after impact of the specimens at the same impact energy, while no obvious effects of void contents on the bending modulus are observed.

Abstract: The effects of voids on the residual tensile strength after impact of CFRP laminates were discussed in this paper. Impact tests on the CFRP laminates with two porosity levels were conducted at five impact energy levels of 3J, 6J, 9J, 12J and 15J at the room temperature. The tensile strength and the tensile modulus of non-impacted specimens decreased 0.67% and 0.086% with the porosity increasing from 0.33% to 0.71%. Compared to non-impact specimens, the residual tensile strength after impact (TAI) and tensile modulus after impact significantly decrease with increasing impact energy. The void contents had the negative effects on the residual tensile strength after impact and tensile modulus after impact of the specimens at the same impact energy.

Abstract: Glass-reinforced Plastics (GRP) has been considered as an alternative material to carbon steel for applications in corrosive environments. The main objective of utilizing GRE pipes is to prevent corrosion and leaks in the pipelines. This increases the reliability of the system by preventing leaks, and thereby also reducing life cycle costs. However, some premature failures had been found after the application of GRP pipes in oil fields. Such failures as fractures around the joint, wrinkles of the inner layer, and circumferential cracks on the body part of the pipeline are the top three major failures which usually appear in practice. This paper analyzes the main causes of these three major failures and attempts to offer several possible solutions to them.

Abstract: Concrete is the most widely used building material in the world. In terms of traffic and bridge construction, concrete is also the most widely used building materials. The cement concrete of the inherent advantages of having a high compressive strength while also has easy to produce cracks, poor impact resistance inherent weaknesses. These weaknesses limit the application of cement concrete. In order to improve the comprehensive quality of the concrete, to further improve the scope of application of cement concrete pavement, the main problems of cement concrete pavement is analyzed. Then the progress of the current hot research field of fiber reinforced concrete is analyzed comprehensively. Finally, on the basis of summing up the status quo, the next step is to study key issues is presented.

Abstract: In this study Eupatorium adenophorum was evaluated as potential raw materials for Water-Absorbent Composite (WAC) synthesized with acrylic acid (AA) and acrylamide (AM) in aqueous medium. Factors, such as weight ratio of AA/AM to dry powdered Eupatorium adenophorum (DPEA), the amount of initiator and cross-linker, neutralization degree of AA, which influence water-absorbent capacity of WAC, were investigated. Additionally, the performances of WACs were appraised in term of water absorbency. The results showed that the nearly optimal WAC was obtained with absorbencies of 933 g/g in deionized water and 310 g/g in 0.9 wt% NaCl aqueous solution. Furthermore, the optimum super-absorbent has been proved with expectant polymerization structures and the morphological features via Fourier Transform Infrared Spectroscopy (FT-IR), X-Ray Diffraction (XRD) and Scanning Electric Microscopy (SEM).