Advanced Materials Research Vols. 821-822

Abstract: A kind of phosphate bonding agent was prepared with H3PO4 and Al(OH)3 as the main raw materials in this paper. Phosphate-metal matrix ceramic coating was prepared on the surface of Q235 steel by using the technology of ambient cure with phosphate bonding agent as main body and CuO and SiC as fillers. The influence of the addition of CuO on curing temperature was studied. Meanwhile, the influence of SiC particle size and content on the abrasion resistance of the coating was studied. The result showed that the amount of friction and wear of phosphate-metal matrix ceramic coating was 5.5mg, when the the molar ratio of P and Al was 3:1.3, SiC particle size was D₅₀=18μm, and its particle content was 40%, 20%wt CuO was added.

Abstract: Sulfonated Polybenzoxazoles (sPBO) with sulfonation degree ranging from 10% to 30% were synthesized from 4,6-diaminoresorcinol dihydrochloride (DAR), terephthalic acid (TPA), 5-sulfoisophthalic acid monosodium salt (SIPA) by direct polycondensation in polyphosphoric acid (PPA). The structures of sPBOs were verified by FTIR and elemental analysis. The values of inherent viscosity ranged from 2.56 to 1.12 dL/g and decreased with the increasing of sulfonation degree. TGA analysis showed sPBOs were thermal stable up to nearly 250°C. sPBO/PPA polymerization solution were hot pressed directly to form PPA doped sPBO membranes since sPBO was insouble in common solvents. The PPA doping level was about 340%(wt) per gram of sPBOs by theoretical calculations. The tensile strength of PPA doped sPBOs membrances ranged from 9.1 to 3.2 Mpa. At high temperature, sPBO membranes showed excellent proton conductivity. For instance, sPBO membrane with a sulfonation degree of 10% exhibited a proton conductivity of 0.123 S/cm at 170°C.The experimental results indicated sPBO are promising for proton exchange membranes for high temperature proton exchange membranes.

Abstract: The material removal process of SiC/Al particulate (SiCp/Al) metal matrix composite by micro-wire electrical discharge machining (micro-WEDM) is influenced by many factors interaction, which makes the mathematical model of surface roughness (SR) be difficult to obtain effectively. To solve this problem, experimental study method is conducted under the constraint conditions. In this paper, a central composite design (CCD) testing with 3-factor and 5-level is carried out and SiCp/Al metal matrix composite machining test scheme is designed, and then second-order relational model is established between SR and main power parameters (open-circuit voltage, capacitance, and pulse duration) by using response surface methodology. Through multiple quadratic fitting, the quadratic regression mathematical model of SR is obtained. Constrains of actual machining condition upon the parameters are analyzed further. With the goal of reducing SR of SiCp/Al metal matrix composite by micro-WEDM, the parameters optimization model is established. Particle swarm optimization (PSO) algorithm and its procedure are designed to solve the model. Test proves that the algorithm could achieve optimized process parameters which satisfy multiple constraints rapidly and effectively.

Abstract: This work presents a study on the investigation of recycled waste tyre (crumb rubber) as aggregate in the combination of local soil-cement brick. The purpose is to develop a lightweight brick with low thermal conductivity that can produce as low cost materials in local area of Thailand. The different amount of crumb rubber particles at 0, 10, 15, 20, 25, 30 and 40% were replaced to local Ratchaburi soil by weight and then mixed with a constant of Portland cement content at 10%. The mechanical properties were studied and indicated that a significant reduction in sample unit weight, there by resulting in a reduction of compressive strength and flexural strength. The results show that the presence of air voids and crumb rubber particles in the matrix can increase the water absorption but decrease the thermal conductivity. However, according to ASTM indicates that this hybrid material can be used as non-load bearing concrete masonry units (2.45 MPa) and is also suitable for construction as low cost and low energy consumption house in Thailand.

Abstract: Due to the physical properties of the soil between piles discrete，thus，composite pile foundation 's bearing capacity exists some uncertainty. So far, the study of the reliability of composite pile foundation is transform from the allowable stress method to the probability limit state design method. That is to say probability definite value design method. Therefor , determine the resistance subentry coefficient become the key of the design method. This paper introduces the significance of the subentry coefficient and the subentry coefficient of the composite pile foundation. Through the calculation of engineering examples, this article give the values of the subentry coefficient and provide a reference for the design of composite pile later.

Abstract: In this paper, nanocrystalline cellulose (NCC) was prepared from bleached aspen kraft pulp by the method of sulfuric acid hydrolysis. The morphology and the size of NCC were characterized by atomic force microscopy(AFM) and X-ray diffraction(XRD). The acrylic resin /NCC composite was prepared by physical blends of acrylic resin and NCC. The physical-mechanical properties of the film from acrylic resin /NCC composite were measured . The results show that the resulting NCC has a rigid rod-shape structure with crystallinity of more than 80%, 26.51 nm in diameter and 200―400 nm in length. The dosage of NCC has important influnce on the physical-mechnical properties of the film from acrylic resin /NCC composite. The tensile strength, the moisture permeability and water absorption of the film increase with the dosage of NCC notably, the elongation at break of the resulting film decreases compared to the control sample..

Abstract: The grafting mechanism of KH570 in the nanometer ZnO/CeO₂ composite powders is discussed. The influences of the reaction time, amount of coupling agent on the grafting rate are researched based on graft situation characterized with FT-IR and XRD devices. The research shows that the ZnO/CeO₂ can be distributed evenly after be grafted with KH570. As a result, the performance of anti-UV and the lipophilic degree of modified nanometer ZnO/CeO₂ will enhance. The modified nanometer ZnO/CeO₂ will be distributed evenly in spinning solution while the spinning melted with NYLON 6 in high-temperature furnace. When the reaction time is 2 hours, the mass ratio of coupling agents and nanoparticle is 0.3, the grafting ratio can reach the maximum.

Abstract: nanotechnology is reviewed in the textile antibacterial deodorant, anti-static, anti-ultraviolet, fade from clean, anti-aging, high wear resistance, high temperature resistant flame retardant, stealth, bionic biodegradable. The latest research progress of Expounds the application of nanometer materials in textile industry, points out that nanotechnology to develop new functional fabrics, enlarge the range of high added value textiles is of great significance

Abstract: A facile synthesis route for monodispersed lead zirconate titanate (PZT) nanoparticles was developed by simple hydrothermal reactions under the assistance of polymer blend including polyvinylalcohol (PVA) and polyacrylate acid (PAA). It was found that PZT particles with an average size of 2.6 nm as well as a very narrow size distribution could be obtained with a 19.0 g/L polymers solution under a low KOH concentration of 2 mol/L at 200 °C for 14 h, indicating that the polymer additives played an important role in controlling the morphology and size of PZT crystals. The simple polymer-assistant hydrothermal synthesis is feasible for the mass production of PZT nanoparticles and is expected to be used in the miniaturization of electronic devices.

Abstract: A nanocrystalline HZSM-5 zeolite was directly synthesized by two-stage varying-temperature synthesis method. The effects of second stage time and temperature on the particle size and morphology were of interest. The morphology of particles were specified by scanning electronic microscopy (SEM) and crystallinity of the samples were recorded by X-ray diffraction (XRD) test results. It was observed that second stage time had a strong effect on crystallinity and morphology; a highly crystalline ZSM-5 zeolite with twinned crystals was synthesised at 180 °C, 60h (second stage time and temperature ). The HZSM-5 particles synthesised at 180 °C, 18h (second stage time and temperature ) were 300600 nm in size and constructed by primary HZSM-5 nanocrystals of 20~30 nm.