Advanced Materials Research Vols. 284-286

Abstract: Energy saving of iron-making system and secondary energy recovery are the main approaches for the Chinese steel industry’s sustainable development. The theoretical analysis of secondary energy generation of four typical BF-BOF steel manufacturing processes showed that improving the resource and energy efficiency, and strengthening recovery and rational utilization of by-product gases are the main way of energy saving for steel industry. According to the status of secondary energy recovery of Chinese steel industry, the technological development tendency energy saving, greenhouse gas emission reduction for Chinese steel industry are presented.

Abstract: The stability of the coating is investigated. For the hydrothermal ageing, the result of ageing of glass fiber compatible to resin with ageing of coating, it is obvious to find out that the effect of ageing of glass fiber/resin composite to IFSS is more than ageing of coating. The composites have more depressed. When the coating degraded completely, the IFSS is near to the value of bare glass fiber. Ageing in the different time with different temperature showed that ageing of micro-composite was dependent on this compatible matrix. However, ageing of coating was dependent on its structure.

Abstract: In this paper, crystallization kinetics behavior of a high heat-absorbing PET / TiN nanocomposite ,the effect of the crystallization behavior of adding nanoendothermic agent,and their crystallization rate and crystallization were studied by differential scanning calorimeter (DSC) ,researching the effect of crystallization behavior of PET with modified TiN and using Avrami equation to study non-isothermal crystallization kinetics. The results show that the kinetic rate constant Zc increasing with the increase of cooling rate, the crystallization half time t1 / 2 subsequently reduced, the crystal growth become fast; TiN is a good nucleating agent in PET, improve PET’s crystallization rate, adding TiN reduce the crystallization activation energy. This has important significance to guide nanocomposite processing.

Abstract: New water soluble multiwall carbon nanotubes (MWCNTs) containing silver nanoparticles-grafted-hyperbranched polyglycerols (HPG) nanocomposites were synthesized and characterized successfully. In this work, MWCNTs were opened using HNO₃/H₂SO₄ mixture and filled by metal nanoparticles such as silver nanoparticles through wet chemcial method. Then MWCNTs containing silver nanoparticles (MWCNTs(Ag)) were used as macroinitiator for ring opening polymerization of glycidol and MWCNTs(Ag)-g-HPG nanocomposites were obtained. Structure of nanocomposites was evaluated by TEM, TGA and spectroscopy methods. With the solubility of MWCNTs(Ag)-g-HPG greatly improved, the new nanocomposites exhibit potential application in biomedicine and nanomedicine.

Abstract: Hexakis-(4-aminophenoxy)-cyclotriphosphazene (PN-NH₂) was synthesized through nucleophilic substitution of the chloride atoms of hexachlorocyclotriphosphazene (HCCP) and reduction of the nitro group, and its chemical structure was characterized. As a curing agents for commercial epoxy resin Diglycidyl ether of bisphenol-A (DGEBA) PN-NH₂ was compared with conventional curing agents 4,4-diaminodiphenylsulfone(DDS) and 4,4-diaminodiphenylmethane (DDM). The thermal properties and thermal degradation behaviors of these thermosetted resins were investigated by using thermogravimetric analysis (TGA). TGA studies demonstrated that the thermal properties of the PN-NH₂-containing cured epoxy resin were higher than those of others. The phosphorus-nitrogen containing curing agent can result in a great improvement of the flame retardance for their thermosetted epoxy resins.

Abstract: Two equations with discrepancies of solid-state displacement reactions between AlN and ZrO₂ were analysed by thermodynamic calculation, and its results were substantiated by experiment. Results of thermodynamic calculation showed that the reaction equation of Bayer and Mocellin proposing could occured at 1411.26K, and it accord with TG-DTA and SEM analysis results, i.e. the reaction equation of Bayer and Mocellin proposing was true.

Abstract: Thermoplastic composites are eco-friendly to environment. In this study, PET/PP thermoplastic composite laminates were produced by interleaving polypropylene (PP) sheets with polyethylene terephthalate (PET) plain fabrics in the condition of varying thermocompression temperature, pressure and time. Afterwards, peel resistance, tensile and impact properties of PET/PP thermoplastic laminates were tested. And the tensile and impact performance of PET/PP laminates was respectively about 40 % and 320 % higher than PP laminates. It was shown that when thermal compressing under pressure of 40 Kg/cm2 at 230 °C for 0.5 minute, PET/PP thermoplastic laminates had optimum tensile and impact properties.

Abstract: In this paper, Ca²⁺-montmorillonite (Ca²⁺-Mt) was modified with cationic surfactant hexadecyl trimethyl ammonium Bromide (CTAB) directly, without changing Ca²⁺-Mt into Na⁺-montmorillonite (Na⁺-Mt). X-ray diffraction (XRD), thermogravimetric analysis (TGA), Fourier transform infrared spectroscopy (FT-IR), contact angle tests and rotary viscosity tests were used to characterize the structure and property of the organo-montmorillonite. The results of XRD show that interlayer space (d₀₀₁) of the product is 4.05nm. The results of TGA indicate the ratio of weight loss of the organic components in the product is 37.7%. The results of FT-IR indicate there are organic components and hardly any water molecules in the product. All these findings indicate that the CTAB has intercalated into the galleries of Ca²⁺-Mt. Contact angle tests shows the product is well hydrophobic and the hydrophobic property is as good as that of organo-montmorillonite modified from Na⁺-Mt. Rotary viscosity tests show that the viscosity of the product at the rotational speed of 6R/min is 1226mPa·s, much better than that of the organo- montmorillonite modified from Na⁺-Mt which is 1070 mPa·s. The thixotropy index of the product is 9.22, much better than that of the organo-montmorillonite modified from Na⁺-Mt which is 5.88. It can be concluded that organo-montmorillonite with perfect interlayer expansion and thixotropic property was prepared by modifying Ca²⁺-Mt with CTAB directly.

Abstract: In the emulsion system, styrene, acrylate monomers and montmorillonite (Mt) were used to prepare interpenetrating polymer network/montmorillonite (IPN/Mt) nano-composite. X-ray diffraction (XRD), transmission electron microscopy (TEM) and dynamic mechanical analysis (DMA) were used to characterize the structure and damping property of the new material. Results of XRD and TEM showed that the layer structure of Mt was destroyed and Mt dispersed in the polymer matrix by single layer. The result of DMA indicated that the damping property of Styrene-Acrylic IPN/Mt was much better than that of Styrene-Acrylic IPN. Damping value of the Styrene-Acrylic IPN/Mt was well improved and the maximum of tanδ increased from 0.621 to 0.739, with a broad damping domain ranging from -41°C to 140+°C. All these findings indicated that styrene-acrylate IPN /Mt nano-composite of broad damping temperature range and high damping value was successfully prepared.

Abstract: The nano Al₂O₃ -Cu/Cr composite was prepared by a simplified internal oxidation technique of the vacuum hot-press sintering-internal oxidizing method. The tensile strength and microhardness were determined respectively. The microstructures were analyzed by means of a scanning electron microscope (SEM). On the basis of above results, the main strengthening mechanisms were investigated by quantitative calculation of several strengthening effects. The experimental results show that the microhardness and tensile strength obviously increase with increased cold deformation. The main strengthening mechanisms of the nano Al₂O₃ -Cu/Cr composites are mainly attributed to the dispersion of the nano-scale of alumina particles and the aggregate of the Cr particle phase, of which the former can restrict the mobility of the dislocations and increase the density of dislocations. Meanwhile, the cold deformation strengthening has some important effect to a certain extent.