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The influence of diblock copolymer addition on the tack properties of a polyacrylic triblock copolymer/tackifier system was investigated. For this purpose, poly(methyl methacrylate)‐block‐poly(n‐butyl acrylate)‐block‐poly(methyl methacrylate) triblock copolymer (MAM) and a 1/1 blend with a diblock copolymer consisting of the same components (MA) were used as base polymers, and a tackifier was added in amounts ranging from 10 to 30 wt %. The temperature dependence of tack was measured by a probe tack test. The tack of MAM/MA at room temperature was significantly higher than that of MAM, and the improvement of MAM/MA upon the addition of the tackifier was higher than that of MAM. The peeling process at the probe/adhesive interface during the probe tack test was observed using a high‐speed microscope. It was found that for MAM/MA, cavitation was caused in the entire adhesive layer, and peeling initiation was delayed by the absorption of strain energy due to deformation of the adhesive layer. In contrast, for MAM, peeling progressed linearly from the edge to the center of the probe. The greater flexibility of the soft block chain in the diblock copolymer resulted in improved interfacial adhesion. 1H pulse nuclear magnetic resonance analysis showed that the addition of the tackifier improved the cohesive strength of the adhesive. Adhesion strength is affected by two factors: the development of interfacial adhesion and cohesive strength. In the MAM/MA/tackifier system, the presence of MA and the tackifier improved the interfacial adhesion and cohesive strength, respectively. © 2012 Wiley Periodicals, Inc. J. Appl. Polym. Sci., 2013

Structure D 2000 Structural Phase Transition and Magnetic Properties of Double Perovskites Ba2CaMO6 (M: W, Re, Os). -The title compounds are characterized by powder XRD, magnetic susceptibility, and specific heat measurements. Both the Re and W containing compounds show structural phase transitions at low temperatures. Ba2CaReO6 undergoes a second order transition from cubic Fm3m to tetragonal I4/m near 120 K. Ba 2 CaWO 6 crystallizes in the space group I4/m at 295 K and the transition to monoclinic I2/m occurs below 220 K. The Re and Os containing compounds transform to an antiferromagnetic state below 15.4 and 51 K, respectively. -(YAMAMURA*, K.; WAKESHIMA, M.; HINATSU, Y.; J. Solid State Chem. 179 (2006) 3, 605-612; Div. Chem., Grad. Sch. Sci., Hokkaido Univ., Sapporo 060, Japan; Eng.) -W. Pewestorf 24-008

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This paper describes a method for producing [Formula: see text]-Al2O3 at low temperatures by a combination of a hydrothermal process and a seeding technique. White aluminum hydroxide precipitate was prepared by a homogeneous precipitation method using aluminum nitrate and urea in aqueous solution. Peptization of the precipitate by acetic acid at room temperature transformed it into a transparent alumina sol. The alumina sol was treated with a hydrothermal process. [Formula: see text]-Al2O3 particles serving as seeds were added to the hydrothermally treated alumina sol. The sol containing the [Formula: see text]-Al2O3 particles was transformed into an [Formula: see text]-Al2O3-seeded alumina gel by drying at room temperature. The non-seeded alumina gel was amorphous or showed fine crystallites and began to crystallize into [Formula: see text]-Al2O3 at 900[Formula: see text]C. The [Formula: see text]-Al2O3-seeding promoted the crystallization of the alumina gel to [Formula: see text]-Al2O3. A remarkable [Formula: see text]-Al2O3 crystallinity was achieved with an increase in [Formula: see text]-Al2O3 particle content by weight in the final seeded alumina gel. For an [Formula: see text]-Al2O3 particle content of 5%, the seeded alumina gel was partially crystallized to [Formula: see text]-Al2O3 by annealing at temperatures as low as 600[Formula: see text]C.