Advanced Materials Research Vol. 1088

Abstract: In this research the aim was produce and evaluate a plastic composite using recycled polypropylene (PP) and fibers from sugarcane bagasse residues (SC), without the use of additives. This analysis was based on laboratorial tests for physical and mechanical characterization, according to the standards ASTM D256-00, D638-101 and D570-98 were analyzed: water absorption, thickness swelling, impact resistance, tensile strength and its correspondent deformation. For comparison it was elaborated three different compositions: 100% PP; 80% PP+20%SC; 70%PP+30%SC. The results indicate a positive correlation with the content of fiber and water absorption and thickness swelling. In the tension tests, the composites with fibers increase the value of resistance for physical efforts, bringing advantages as durability and integrity of the material, showing a viability of the composites.

Abstract: This research evaluated, with the of the analyses of variance (ANOVA), a composite material based on epoxy matrix phase reinforced with Portland cement (CP-II) particles (0%wt [100%wt of resin], 20%wt, 40%wt, 60%wt). The response-variable investigated were modulus of elasticity (E) and compressive strength (S), bulk density (ρ_B), apparent density (ρ_A) and porosity (P). The highest values of the modulus of elasticity were provided from the composites manufactured with 40wt% of cement addition. The inclusion of 60% of cement implies in a reduction in the mechanical properties when compared with the results of the composite manufactured with 40% of cement. For the physical properties, the gradually inclusion of cement provides increasing in the density of the composites, and reduce the porosity of the materials manufactured.

Abstract: These research objectives the development and evaluation of physical and mechanical properties of a hybrid composite manufactured epoxy resin reinforced by Eucalipto sp. wood sawdust and treated piassava fibers. The evaluated properties were modulus of elasticity (MOE) and modulus of rupture (MOR) in static bending, water absorption after 24 hours, porosity and apparent density. Three factors with two levels was evaluated: thickness (3 mm and 4 mm), volumetric resin fraction (45% and 50%) and the use or not of laminate piassava fibers reinforcement, leading to a factorial design of 23 type. Were manufactured four panels, two with 50% and two with 55% of resin, using casting method. For the physical and mechanical properties obtained, the better conditions were the one that uses 50% of epoxy resin, 55% sawdust mass fraction and with the use of laminated piassava fibers reinforcement. The thickness was not statistically significant in obtaining the properties evaluated.

Abstract: Melamine formaldehyde (MF) resin and its derivatives are always considered to be an excellent flame retardant material, which has a wide application in the flame retardant fabric, thermal insulation and high temperature filter Materials etc. The melamine formaldehyde resin (MF) and polyvinyl alcohol (PVA) blend electrospinning were studied in this work. MF-PVA electrospun fiber membrane was successfully prepared, and the limit oxygen index (LOI), scanning electron microscopy (SEM), infrared spectrum (IR) and X-ray diffraction (XRD) have been used to analyze and characterize the fiber. The results show that: The blending fiber is endowed with effective flame retardant property by the amino group and triazine ring group in MF/PVA fibers, and the LOI reaches 28~31. The MF and PVA blend fiber showed best uniformity when the blending solid content ratio of MF-PVA is 1:1. MF/ PVA blend fiber has certain crystallization capacity, which influences both the mechanical properties and flexibility of blending fiber.

Abstract: Melamine formaldehyde (MF) resin and its derivatives are always considered to be excellent flame retardant material, which has wide application in the flame retardant fabric, high temperature insulating filter materials, etc. However, less research on electro-spinning of melamine fiber has been reported, recently. In the study, the molar ratio, condensation polymerization temperature of formaldehyde and melamine, and the law of effect in different solid content ratio of melamine formaldehyde/polyvinyl alcohol on the electro-spinning were studied. The results showed that the best conditions for spinning were that formaldehyde and melamine molar ratio was 1:1.7, the reaction temperature was 80°C, and the MF-PVA blending solid content ratio was 1:1, meanwhile the morphology of Electron microscopy indicated the good uniformity of the fiber. The fiber presents good flame retardant property in conditions of MF-PVA blending solution viscosity 155mPa ́s, limit oxygen index 33.2%.

Abstract: Increasing concerns on global warming and current environmental issues have directed research attention to the problems of energy saving, alternative energy sources, as well as to the improvement of the efficiency of existing chemical current sources. A particular focus is currently concentrated on solar energy use. High-purity silicon plates are employed as details in solar cells. Over the past ten years researchers have sought to create silicon nanomaterials able to significantly improve the efficiency of lithium-ion electrochemical batteries and photovoltaic cells. It is a common knowledge that the principle industrial method for producing high-purity silicon is based on vapor deposition; for example Siemens process [1]. However, it has a number of drawbacks in terms of power consumption, costly reagents, and sophisticated equipment. The development of a low-cost production process for solar and nanocrystalline silicon seems therefore an interesting research task. An alternative approach to the production of silicon is electrodeposition from molten salts containing silicon ions [2-7]. This method can be applied to obtain both coherent covers and Si-nanostructures, such as nanopowders and nanofibres.

Abstract: A novel polypropylene strong acid cationic exchange fiber (SACEF) was prepared by sulphonation reaction of polypropylene graft styrene (PP-g-St) fiber, using 1,2-dichloroethane as swelling agent. Factors effected the adsorption capacity of SACEF synthesized from PP-g-St fiber, such as swelling time, grafting degree of PP-g-St, liquor ratio (mass of fiber vs. volume of the reaction reagent), reaction temperature, and sulfuric acid concentration were investigated. The results showed that the average adsorption capacity of SACEF was 4.42 mmol·g^-1.

Abstract: By blending the different ratio of the low viscosity of bisphenol A type epoxy resin with low viscosity ammonia catalytic phenolic resin, the performance of the resin systems were investigated by the gel time, viscosity, mechanical properties, heat resistance, flame retardance. In addition, DSC was used to detect the thermal property, and FT-IR monitored the reactive process of phenolic-epoxy resin. When the phenolic resin was mixed with 5% epoxy resin, the results were as follow: the gel time of 121 s at 150°C, viscosity of 7760 mPa·s at 30°C, flexural strength of 83.3 MPa, impact strength of 6.9 kJ/m², tensile strength of 20 MPa, heat deflection temperature of 148.5°C, oxygen index of 34.5% and the apparent cure activation energy of 94.2kJ/mol. The resin systems had higher service temperature, low viscosity, excellent mechanical properties and service characteristics, and it could meet the requirements of fast pultrusion process.

Abstract: In this paper, waterborne damping coating with excellent performance was prepared by self-made acrylic resin, and its physical and mechanical properties, chemical resistance, and damping properties (damping factor) were studied.

Abstract: Tri-block poly (lactide)-poly (ethylene glycol)-poly (lactide), diacrylated derivative and the cypermethrin-loaded microcapsule were prepared, respectively. The structure of the copolymer was characterized by ¹HNMR, FTIR, TGA and DSC. The microcapsules were characterized by OM(optical microscope), SEM, FTIR, TGA and DSC. The encapsulation efficiency of the microcapsules is 91.3%. The microcapsules showed good dispersity and sustained release behavior in 50% ethylene glycol aqueous solution.