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Volume Concentration (volume + concentration)

Distribution by Scientific Domains
Polymers and Materials Science100%

Selected Abstracts

The role of auxiliary monomers and emulsifiers on wet scrub resistance of various latex paints at different pigment volume concentrations

JOURNAL OF APPLIED POLYMER SCIENCE, Issue 5 2009
M. Khorassani
Abstract This work is an attempt to study the effect of different latex types containing various auxiliary monomers and emulsifiers on their pigmentation and their corresponding behavior on scrub resistance. The auxiliary monomers investigated were acrylic acid (AA), methacrylic acid (MAA), and itaconic acid and the emulsifiers contained sodium lauryl sulfate (SLS) and sodium dodecylbenzene sulfonate (SDBS). It was shown that a semibatch polymerization technique which led to smaller particles and sharper size distributions is preferable. The best wet scrub results were obtained by using MAA and SLS. It was also shown that the proper selection of an auxiliary monomer generally depended on the range of incorporated pigment volume concentration (PVC). At high PVCs, AA gave better performances compared with MMA. The reverse effect was shown to occur at low PVCs. © 2009 Wiley Periodicals, Inc. J Appl Polym Sci, 2009 [source]

Effects of bivalve shell particles of hyriopsis cumingii on the performances of epoxy resin studied by positron annihilation

JOURNAL OF APPLIED POLYMER SCIENCE, Issue 6 2008
Xudong Sun
Abstract Mussel shell particles sized in micrometer level have been prepared with a ball mill. The X-ray powder diffractrometer (XRD) and Fourier transform infrared (FTIR) results proved that the shell particles contained mainly CaCO3 in the form of aragonite, together with small amount of organic phase. EP modified with shell particles showed a much rougher fracture surface than unfilled EP. The mechanical properties have been improved obviously by adding the shell particles in EP from 1% to 5%. The particle would occupy a number of free volume holes of the EP matrix. This would lead to a decrease in the total free volume concentration of the composites. The particles acted as a bridge to make more molecules interconnected for the good interfacial adhesion, resulting in a reduction of the free volume hole size in the interfacial layers. I2 reached its highest value when 3% shell particles were added and then decreased as the shellparticles content increased. © 2008 Wiley Periodicals, Inc. J Appl Polym Sci, 2008 [source]

Ultra-Small-Angle X-Ray Scattering Study of PET/PC Nanolayers and Comparison to AFM Results

MACROMOLECULAR CHEMISTRY AND PHYSICS, Issue 13 2008
Fernando Ania
Abstract The forced assembly of two immiscible polymers, produced by layer-multiplying co-extrusion, is analyzed by means of USAXS. Comparison of scattering and AFM results sheds light on many details of the nanolayered structure in PET/PC films. The role played by the volume concentration and cold crystallization of PET on the experimental scattering is discussed. The appearance of at least two scattering maxima in all cases, corresponding to higher orders of the same repeating distance, accounts for the high regularity of the developed nanostructure. It is finally shown that long spacing values, derived from a localized area in AFM, are in a good agreement with the USAXS values averaged over much larger areas. [source]

The role of auxiliary monomers and emulsifiers on wet scrub resistance of various latex paints at different pigment volume concentrations

JOURNAL OF APPLIED POLYMER SCIENCE, Issue 5 2009
M. Khorassani
Abstract This work is an attempt to study the effect of different latex types containing various auxiliary monomers and emulsifiers on their pigmentation and their corresponding behavior on scrub resistance. The auxiliary monomers investigated were acrylic acid (AA), methacrylic acid (MAA), and itaconic acid and the emulsifiers contained sodium lauryl sulfate (SLS) and sodium dodecylbenzene sulfonate (SDBS). It was shown that a semibatch polymerization technique which led to smaller particles and sharper size distributions is preferable. The best wet scrub results were obtained by using MAA and SLS. It was also shown that the proper selection of an auxiliary monomer generally depended on the range of incorporated pigment volume concentration (PVC). At high PVCs, AA gave better performances compared with MMA. The reverse effect was shown to occur at low PVCs. © 2009 Wiley Periodicals, Inc. J Appl Polym Sci, 2009 [source]

Evidence of Nearest-Neighbor Ordering in Wet-Processed Zirconia,Nickel Composites

JOURNAL OF THE AMERICAN CERAMIC SOCIETY, Issue 10 2001
Carlos Pecharromán
Monolithic zirconia,nickel (ZrO2/Ni) cermets have been prepared by a wet-processing method with nickel volume concentrations of 16%,40%. Microstructural analysis performed on scanning electron microscopy images has revealed evidence of a partial ordering of metallic particles inside the ceramic matrix. This ordering does not appear in mullite/molybdenum cermets. Complex impedance measurements have shown that the percolation threshold of ZrO2/Ni cermets appears at a filling factor (fc) of 0.34, exceeding the theoretical value (fc= 0.16), as a consequence of its microstructural order. Electrical measurements display the expected increase of capacity near the percolation threshold. These results open the possibility to design new devices with the appealing electric, magnetic, and mechanical properties that are predicted by the percolation theory. [source]