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Softening Point (softening + point)
Selected AbstractsIn situ SAXS studies of the morphological changes of an alumina,zirconia,silicate ceramic during its formationJOURNAL OF APPLIED CRYSTALLOGRAPHY, Issue 4 2006Rudolf Winter Small-angle X-ray scattering is used at two energies, one either side of the zirconium K -edge, to probe the in situ formation of an alumina,zirconia,silicate ceramic. The use of energies either side of the edge allows the decomposition of information regarding the scattering from the zirconia particles from that of the glass matrix. Porod slope data show how the nanoparticles progress from being relatively isolated particles to becoming agglomerates as the pore network in the glass collapses. The shape of the agglomerates resembles the pore network of the glass at low temperature. The Guinier radii of the particles show the growth of the agglomerates past the Littleton softening point, whilst still resolving the primary particles. [source] Correlation of morphology, rheology, and performance improvement in gasoline tubes based on PA-6 nanocompositesJOURNAL OF VINYL & ADDITIVE TECHNOLOGY, Issue 3 2010Mehdi Moghri PA-6/organo-modified layered silicate nanocompounds were prepared by the melt mixing of PA-6 with different nanoclay loadings in a corotating twin-screw extruder. Gasoline tubes based on these nanocompounds were produced at different silicate loadings. Thermal, mechanical, rheological, and barrier properties of the different samples were investigated and correlated to their morphology. Transmission electron microscopy, wide angle X-ray scattering, and linear melt state viscoelastic measurements were used to characterize the different aspects of nanoclay dispersion in the nanocomposite samples. While tensile modulus, softening point, heat distortion temperature, and gasoline barrier properties of the prepared tubes were improved considerably by increasing the clay content, performance improvement with respect to clay content (after a certain value) decreased with increasing clay loading. It could be attributed to the re-agglomeration of tactoids at higher concentrations. These findings were correlated with the rheological and morphological observations. J. VINYL ADDIT. TECHNOL., 2010. © 2010 Society of Plastics Engineers [source] Modification of waterproofing asphalt by PVC packaging wasteJOURNAL OF VINYL & ADDITIVE TECHNOLOGY, Issue 4 2009Changqing Fang Recycled packaging waste poly(vinyl chloride), instead of an ordinary polymer modifier, was adopted for the modification of an asphalt waterproofing membrane. The physical performance of the membrane was studied. Results showed that the softening point of the modified asphalt was increased, while the penetration degree was reduced. Also, under natural aging conditions, the tension, the retention of extension under the greatest tension, and the retention of low-temperature flexibility were all improved significantly. At the same time, the resistance to acid, alkali, and salt corrosion of the modified waterproofing membrane was improved. The mechanism of the modification was studied by Fourier transform infrared spectroscopy and microstructure analysis. J. VINYL ADDIT. TECHNOL., 2009. © 2009 Society of Plastics Engineers [source] Effect of montmorillonite on properties of styrene,butadiene,styrene copolymer modified bitumenPOLYMER ENGINEERING & SCIENCE, Issue 9 2007Jianying Yu Clay/styrene,butadiene,styrene (SBS) modified bitumen composites were prepared by melt blending with different contents of sodium montmorillonite (Na-MMT) and organophilic montmorillonite (OMMT). The structures of clay/SBS modified bitumen composites were characterized by XRD. The XRD results showed that Na-MMT/SBS modified bitumen composites may form an intercalated structure, whereas the OMMT/SBS modified bitumen composites may form an exfoliated structure. Effects of MMT on physical properties, dynamic rheological behaviors, and aging properties of SBS modified bitumen were investigated. The addition of Na-MMT and OMMT increases both the softening point and viscosity of SBS modified bitumens and the clay/SBS modified bitumens exhibited higher complex modulus, lower phase angle. The high-temperature storage stability can also be improved by clay with a proper amount added. Furthermore, clay/SBS modified bitumen composites showed better resistance to aging than SBS modified bitumen, which was ascribed to barrier of the intercalated or exfoliated structure to oxygen, reducing efficiently the oxidation of bitumen, and the degradation of SBS. POLYM. ENG. SCI., 47:1289,1295, 2007. © 2007 Society of Plastics Engineers [source] Effect of Technological Factors on Electrochemical Hydrogenation of LigninTHE CANADIAN JOURNAL OF CHEMICAL ENGINEERING, Issue 4 2002Jianan Zhang Abstract Lignin properties were improved by electrochemical hydrogenation. Various technological factors, such as cathode materials, temperature and concentrations of water, solvent, substrate, on the electrochemical hydrogenation of lignin in divided electrolytic cell were studied. The results showed that the hydrogen content (H %) and ratio of hydrogen to carbon (H/C) of hydrogenated lignin (HL) increased by 1.7 % and 0.04, respectively, and the softening point (SP) decreased by 24°C in comparison with lignin raw material. It was feasible for lignin to be electrochemically hydrogenated. Les propriétés de la lignine ont été améliorées par hydrogénation électrochimique. Divers facteurs technologiques, tels que le matériau des cathodes, la température et les concentrations de l'eau, du solvant, du substrat, sur l'hydrogénation électrochimique de la lignine dans une cellule électrolytique divisée, sont étudiés. Les résultats montrent que la teneur en hydrogène (H %) et le rapport entre l'hydrogène et le carbone (H/C) de la lignine hydrogénée (HL) augmente de 1,7% et 0,04, respectivement, et que le point d'adoucissement (SP) diminue de 24°C comparativement au matériau brut de la lignine. La lignine a pu être hydrogénée électrochimiquement. [source] Effects of circulating fluidized bed combustion (CFBC) fly ashes as filler on the performances of asphaltASIA-PACIFIC JOURNAL OF CHEMICAL ENGINEERING, Issue 2 2009Qin Li Abstract This work investigated the potential of utilizing circulating fluidized bed combustion (CFBC) fly ashes (CFAs) as alternative filler, substituting mineral powders (MPs) that are widely used in asphalt concrete. Physico-chemical characteristics of the CFAs and MPs, as well as effects of different mix designs of CFAs and asphalt on asphalt performances were examined, including moisture susceptibility, viscosity, ductility, softening point, penetration, and antiaging performances. The results of the study show that generally the CFAs have greater effects than the MPs on improving the performances of asphalt, and that the specific surface area (SSA), free CaO (f-CaO), morphology, and mineralogical phases of the CFAs are more favorable than those of the MPs respectively, while the alkaline values, hydrophilic coefficients, particle size distributions (PSDs), and water contents of the two fillers are similar. It is suggested that CFAs may be more suitable than MPs for the use as asphalt concrete filler. Copyright © 2009 Curtin University of Technology and John Wiley & Sons, Ltd. [source] Synthesis and characterization of novel biodegradable aliphatic poly(ester amide)s containing cyclohexane unitsJOURNAL OF POLYMER SCIENCE (IN TWO SECTIONS), Issue 6 2006Hélène A. Lecomte Abstract Polyesters provide a good basis to work on for designing novel biodegradable materials that are also mechanically and thermally resistant. In this study, a series of aliphatic poly(ester amide)s (PEA) based on cyclohexane units was synthesized. Block-copolymers of cyclohexyl sebacate and cyclohexyl sebacamide were produced by controlling the length of the ester block and the amount of amide during a two-step melt/interfacial polycondensation reaction. Films produced from these materials could retain their shape above 373 K due to the physical network of amide hydrogen-bonding. Thermal properties were also evaluated, with various melting and softening points obtained depending on the PEA composition. The determining factor for mechanical properties was the amount of amide introduced, with films containing up to 10 mol % amide showing the best handleability and flexibility. Tensile properties typical of an amorphous viscoelastic material were observed, but with much superior elongation to break achievable (,1700%). These materials were also shown to be hydrolyzable, noncytotoxic, and favorable for cell attachment: they may therefore have a promising future in the area of medical devices or packaging, especially as their properties can be tuned by changing their composition. © 2006 Wiley Periodicals, Inc. J Polym Sci Part A: Polym Chem 44: 1785,1795, 2006 [source] Hot water acid-resistant enamels for sheet steelMATERIALS AND CORROSION/WERKSTOFFE UND KORROSION, Issue 1 2010A. S. Kassem Abstract Several enamel frit recipes were formulated for direct-on application on sheet steel. Their suitability as hot water and acid-resistant coatings were investigated. DTA analyses were performed on raw batches to follow up physico-chemical changes occurring on firing. Then batches with different recipe compositions were fritted and mixed with mill additions. These were then tested for thermal expansion and the corresponding linear coefficients as well as glass transition temperatures and softening points were obtained. Also, the viscosity of molten frits was determined as a function of temperature. These frits were then applied on sheet steel and the following properties were investigated: resistance to hot water, acid resistance, surface gloss, and adherence to steel. It was found that recipe No. 4, containing no manganese dioxide and the highest amount of nickel oxide among all the suggested recipes, gave the best results. The optimum conditions for application on steel sheet were: firing at 850,°C for 5 min. [source] | |||||||||||||