Advanced Materials Research Vols. 150-151

Abstract: . In order to protect cast-in place piles of high speed railway bridge, steel pipes which used to be used during the work progress are left forever to increase the durability of concrete piles. The relative experiments are carried out indoor. On one hand, steel pipe can separate the concrete from exterior environment; on the other hand, under the condition of freezing, steel pipe can produce hoop effect to the concrete which can reduce crack expansion stress because of frost heave. Mass loss, relative dynamic modulus of elasticity and strength about steel pipe concrete are studied. The conclusion shows that the durability of concrete piles with steel pipe protection is much better than common concrete piles with no protection.

Abstract: By using artificial non-homogeneous cores which coefficient of variation is 0.72 to simulate reservoir sandstone, and proceed the research of displacement effect on three aspects, which are polymer molecular weight, polymer solution concentration and reservoir permeability. The results show that polymer solution concentration and polymer molecular weight have greater influence on the displacement efficiency, while reservoir permeability has very little influence when it is more than 700md.

Abstract: Polymer blends of a binary system with limited miscibility are a kind of different surface structure polymer blends which main chains are same as one. The blend of polysulfone (PSf) and carboxylated polysulfone (CPSf) had been made in the solvent of dimethylacelamide (DMAc) or N-methylpyrrolidinone (NMP). The chemical polysulfones containing 0.5,1.0,1.5 and 2.0 carboxylated groups per repeat unit were mixed with Udel 300 polysulfone. The equilibrium time of two-phase polymer in solution presents their degrees of limited miscibility. The two- phase polymers could transfer as miscible blends when they had been annealed at 170 for above 6 days. Annealing of blends below the grass transition temperature(Tg) results in a decrease in enthalpy that is recovered during heating. The enthalpy recovery is visible as an endothermic peak in a differential scanning calorimeter (DSC) scan. The position of this peak depends on the composition of two-phase and on the structure of material itself. Two-sample cells were co-tested in same time for getting several Tg of limited miscible polymer blend and its component respectively. PSf/CPSf polymer blends in liquid-liquid phase separation and molecular weight distribution to be tested by High Performance Gel Permeation Chromatography (GPC). The polymer blends were showing S-O-C strength absorbance between 1000-769/cm and 3300-2500/cm to be detected by Infrared Absorption Spectrum (IR) analysis. Therefore, the reaction and enthalpy of limited miscibility between two-phase of polymer blend PSf/CPSf can be described in the paper.

Abstract: The influence of film forming matter to heat preservation insulation coating reflectivity was studied. Organosilicon modified styrene-acrylic emulsion was selected as film forming matter through the infrared spectrum test. The influence of several kinds of pigment and filler to reflectivity was studied by orthogonal experimental design . Importance of factors from large to small in turn is: Rutile titanium dioxide> Kaolin> expanded perlite、hollow glass microsphere> iron oxide red, and the formula of pigment and filler was determined .The influence of rutile titanium dioxide to reflectivity was studied, the reflectivity of coating is superior when rutile titanium dioxide grain size is in the range between 0.130 m and 0.136 m. Film thickness has certain influence to reflectivity ,when the thickness is 0.062cm, the reflectivity of coating reaches the highest,is 73.28%.

Abstract: It is necessary to improve the adhesion of the cured rubber to a substrate as it is used extensively. It is well known that an improvement in adhesion can be realized by incorporating in the composition a sliane or siloxane. Although the composition provides good adhesion to many kinds of substrates, it has been found that the adhesive bond degrades rapidly under wet conditions. To be solved it, rosin eater was incorprated in the silcone ruber in the paper. Increasing the content of rosin ester could induce a relative high adhesion in hot water. Moreover, when the content of modified rosin pentaerythritol ester was above 4.5 phr, the immersion days in hot water before adhesive failure occured were three times than that of non-additive rosin esters.

Abstract: The primary factor in reducing building energy consumption is the wall energy, but thickening the walls simply and using traditional materials to reduce energy consumption has become unable to satisfy the development trend at the present stage. Energy-saving wall materials include organic wall insulation, inorganic wall insulation and composite wall insulation. According to the construction technology, insulation wall can be divided into internal insulation wall, sandwich insulation wall and external insulation wall etc.. Polyurethane foam and other new energy-saving materials are widely used, whicth will become the main energy-saving materials in the northern cold areas.

Abstract: The effect of density on physical and mechanical properties of phenolic-impregnated cold-pressing reconstituted small-sized bamboo fibrous sheet composite was evaluated. The results indicated that with the density increased from 0.85g/cm3 to 1.20 g/cm3: water absorption decreased, thickness swelling increased first and then decreased; the value of modulus of rupture(MOR) increased from 120MPa to 230MPa, R2 was 0.885; the value of modulus elasticity(MOE) increased from 1.8×104MPa to 2.8×104MPa, R2 was 0.978; the shearing strength (perpendicular loading) increased from 6.5MPa to 18MPa, R2 was 0.978;the shearing strength( parallel loading) increased from 6.3MPa to 26MPa, R2 was 0.973;the compression parallel to grain values increased from 80MPa to 120MPa.

Abstract: Novel pyridine-containing compounds were synthesized and their properties were studied. Organic electroluminescent devices using these compounds as electron-transporting layer were fabricated. It was demonstrated that these compounds were useful for organic light-emitting diodes (OLED) and solid state lighting technology in favor of energy-saving and environmental protection fields.

Abstract: Green tapes were prepared by aqueous tape-casting method with binders of polyvinyl alcohol, styrene-acrylate emulsion and the mixed binders, respectively. Effects of solid content and binders on viscosity of the slurry were investigated by digital rotary viscosimeter. Results show that solid content should be lower than 60wt % with the binder of PVA; solid content could achieve the maximum 73wt% by tape-casting using emulsion as binder. Furthermore, slurry with solid content up to 75wt % had been successfully prepared by tape-casting using mixed binders. Mixed binders are promising additives to produce high solid content green tapes with smooth surface, adequate strength and very good flexibility.

Abstract: The 2-methylimidazole (Im) -terminated hyperbranched polyesters (ImHBPs) with different generations were prepared and used in diglycidyl ether of bisphenol A (DGEBA) as curing agents and tougheners in this work. It was found that the ImHBPs had better latent property than Im which indicated that the ImHBPs were proper to be used as low temperature curing agent in epoxy curing system. It was also found that the tensile strength, the flexural strength and impact strength of epoxy thermosets cured by ImHBPs under 90 were much higher than those of CYD-128/2-methylimidazole thermoset, which indicated that the ImHBPs obviously improved the mechanical properties of epoxy thermosets, and the thermoset cured by ImHBP with two generation had the best performance among the thermosets.