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  • 1
    Electronic Resource
    Electronic Resource
    Compressibility factor of polar fluids in the gaseous and liquid regions (1973)
    Hoboken, NJ : Wiley-Blackwell
    AIChE Journal 19 (1973), S. 1227-1233 
    Details
    ISSN: 0001-1541
    Keywords: Chemistry ; Chemical Engineering
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology , Process Engineering, Biotechnology, Nutrition Technology
    Notes: The tables of Pitzer et al. for the compressibility factor of nonpolar substances have been extended to polar fluids for the gaseous and liquid regions for reduced temperatures from 0.8 to 1.15 and reduced pressures from 0.2 to 6.0. Available experimental PVT data for polar fluids were related to the acentric factor and fourth parameter at constant reduced temperature and pressure by a quadratic least squares procedure. The resulting relationships reproduced the data utilized with good accuracy for the entire region considered.
    Additional Material: 1 Ill.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1002/aic.690190621
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  • 2
    Electronic Resource
    Electronic Resource
    Optical anisotropy of polymeric films measured by waveguide propagation mode determination (1992)
    Bognor Regis [u.a.] : Wiley-Blackwell
    Journal of Polymer Science Part B: Polymer Physics 30 (1992), S. 1507-1514 
    Details
    ISSN: 0887-6266
    Keywords: poly(p-phenylenebenzobisthiazole) ; Mylar ; polymeric film ; waveguide ; refractive index ; linear attenuation coefficient ; optical anisotropy ; Chemistry ; Polymer and Materials Science
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology , Physics
    Notes: Extruded thin films of a liquid-crystalline charge-conjugated rigid-rod polymer poly(p-phenylenebenzobisthiazole), PBT, and a semicrystalline thermoplastic polyethylene-terephthalate (Mylar) were fabricated and examined for film thickness, refractive index, and linear attenuation coefficient. Optical waveguide modes were successfully induced on the polymeric films using a prism coupler at λ = 633 and 1300 nm. Highly consistent thickness values were obtained for the polymeric films. In addition, the anisotropic nature of the optical properties was determined using TE and TM propagation modes. A refractive index as high as 2.3 was observed on PBT film. The refractive index data suggested that the PBT and Mylar films were optically anisotropic with refractive indices n⊥ (out-of-plane) invariably smaller than n∥ (in-plane). Large anisotropy was also discovered in the linear attenuation coefficient α, with α∥/α⊥ ≈ 50 for the Mylar films. Complementary polarimetric and spectroscopic interference measurements were also applied to investigate the optical anisotropy of the extruded polymeric films. © 1992 John Wiley & Sons, Inc.
    Additional Material: 6 Ill.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1002/polb.1992.090301309
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  • 3
    Electronic Resource
    Electronic Resource
    Characterization, processing, and properties of an aromatic poly (ether ketone) (1991)
    Bognor Regis [u.a.] : Wiley-Blackwell
    Journal of Polymer Science Part B: Polymer Physics 29 (1991), S. 119-128 
    Details
    ISSN: 0887-6266
    Keywords: Chemistry ; Polymer and Materials Science
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology , Physics
    Notes: Poly(oxy-1,3-phenylenecarbonyl-1,4-phenylene), mPEK, was synthesized in a methane sulfonic acid/phosphorus pentoxide medium through the polycondensation of 3-phenoxybenzoic acid. The polymer was soluble at room temperature in strong acids and common organic solvents. Differential scanning calorimetry on mPEK indicated a glass transition temperature of 132°C and no detectable crystal melting behavior. The polymer was thermo-oxidatively stable up to 420°C in air as determined by thermogravimetric analysis. Thermal degradation resulted in a crosslinked polymer. Compression molding was successfully applied to consolidate mPEK powder into bulk specimens without causing degradation. Tensilefractured surfaces of the consolidated specimens were examined by scanning electron microscopy which strongly indicated adequate fusion of mPEK powder but also disclosed microvoids of uniform size, shape, and distribution. X-ray scattering revealed that mPEK powder was amorphous and that the consolidated mPEK specimens were structurally isotropic as well as amorphous. The bulk specimen density was determined to be 1.29 ± 0.01 g/cm3 and the three-dimensionally isotropic bulk tensile properties were shown to be 4.10 ± 0.10 GPa (modulus), 0.07 ± 0.01 GPa (strength), and 0.021 ± 0.006 (elongation at break). Tensile properties of the amorphous mPEK specimens compared favourably with literature values of state-of-the-art semicrystalline thermoplastics. Crystaline phases could be realized for mPEK by melt-processing, or precipitating from a solvent.
    Additional Material: 11 Ill.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1002/polb.1991.090290115
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  • 4
    Electronic Resource
    Electronic Resource
    Bulk rigid-rod molecular composites of articulated rod copolymers with thermoplastic pendants (1992)
    Bognor Regis [u.a.] : Wiley-Blackwell
    Journal of Polymer Science Part B: Polymer Physics 30 (1992), S. 1515-1525 
    Details
    ISSN: 0887-6266
    Keywords: articulated rigid rod ; grafted thermoplastic ; copolymer ; molecular composite ; phase separation ; consolidation ; aspect ratio ; Halpin-Tsai equation ; three-dimensionally isotropic properties ; Chemistry ; Polymer and Materials Science
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology , Physics
    Notes: Bulk rigid-rod molecular composites were successfully obtained by powder consolidation of a copolymer containing both the reinforcing rigid-rod segments and the thermoplastic matrix. By chemically linking the reinforcing segments and the matrix molecule, the copolymer was designed to minimize phase separation in the molecular composite. The copolymer was an articulated rigid-rod poly(p-phenylenebenzobisthiazole), aPBT, with an aromatic poly(ether ketone), mPEK, thermoplastic pendant grafted at the points of articulation. The copolymer powder was pre-formed and compression molded at an elevated temperature, which resulted in bulk rigid-rod molecular composites with three-dimensionally isotropic properties. Compared to the neat mPEK homopolymer, significant increases in glass transition temperature Tg and tensile properties have been realized for the aPBT-g(mPEK) copolymers with low rod content. Taking into account the aspect ratio of the aPBT, the bulk rigid-rod molecular composite showed a tensile modulus as predicted by the Halpin-Tsai equation. In addition, x-ray scattering revealed minimal rod aggregation. However, for the copolymer of higher rod content, significant phase separation was observed in the copolymer powder, which resulted in a decrease in Tg as well as reinforcement efficiency of the bulk rigid-rod molecular composite as compared to those derived from the copolymers of low rod content. © 1992 John Wiley & Sons, Inc.
    Additional Material: 8 Ill.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1002/polb.1992.090301310
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  • 5
    Electronic Resource
    Electronic Resource
    Axial X-ray scattering on high-performance polymeric fibers (1994)
    Bognor Regis [u.a.] : Wiley-Blackwell
    Journal of Polymer Science Part B: Polymer Physics 32 (1994), S. 2575-2583 
    Details
    ISSN: 0887-6266
    Keywords: x-ray scattering ; fiber ; axial ; transverse ; isotropic ; anisotropic ; poly(p-phenyleneterephthalamide) ; PPTA ; Kevla ; fibers ; poly-2,5-benzoxazole ; ABPBO ; rod-like ; poly(p-phenylenebenzobisoxazole) ; PBO ; Chemistry ; Polymer and Materials Science
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology , Physics
    Notes: High-temperature polymers were spum from liquid-crystalline solutions into fibers of superior thermal stability and mechanical properties. Fibers of two extended-chain polymers poly(p-phenyleneterephthalamide), PPTA, and poly-2,5-benzoxazole, ABPBO, as well as a rod-like polymer poly(p-phenylenebenzobisoxazole), PBO, were examined by axial x-ray scattering. Both wide-angle scattering and small-angle scattering were performed with CuKα radiation aiming along the fiber axis (c-axis) for structural information on the a-b lattice plane. In addition to previously reported lattice structure, the PPTA fibers (Kevlar® 29, 49, and 149) showed strong [004] and a [022] reflections suggesting that segments of the PPTA molecules were transverse to the fiber axis. This unique fiber structure is more prominent and the void content is less for the PPTA fibers with higher tensile modulus, (i.e., Kevlar® 149 〉 Kevlar® 49 〉 Kevlar® 29). Similar measurements on thermally annealed ABPBO and PBO fibers showed no [00l], [h0l], or [0kl] reflection indicative of a truly uniaxial molecular orientation. Evidence of microfibrillar order was discovered for the Kevlar® fibers and the ABPBO fiber. Results of conventional x-ray scattering on these fibers were compared and reconciled. © 1994 John Wiley & Sons, Inc.
    Additional Material: 12 Ill.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1002/polb.1994.090321603
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  • 6
    Electronic Resource
    Electronic Resource
    Ionic conductivity of conjugated water-soluble rigid-rod polymers (1993)
    Bognor Regis [u.a.] : Wiley-Blackwell
    Journal of Polymer Science Part B: Polymer Physics 31 (1993), S. 1941-1950 
    Details
    ISSN: 0887-6266
    Keywords: rigid-rod polymer ; cation ; dialysis ; molecular weight ; cast ; aggregated ; isotropic ; anisotropic ; film ; depletion measurement ; ionic conductivity ; x-ray scattering ; Chemistry ; Polymer and Materials Science
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology , Physics
    Notes: Poly[(1,7-dihydrobenzo[1,2-d:4,5-d′] diimidazole-2,6-diyl)-2-(2-sulfo)-p-phenylene], a conjugated rigid-rod polymer, was derivatized with pendants of propane-sulfonated ionomers. The derivatized rigid-rod polymer was soluble in aprotic solvents as well as in water for isotropic solutions that were processed into isotropic films. Direct-current electrical conductivity σ of the films was measured using the four-probe technique. Room-temperature σ as high as 2.9 × 10-4S/cm was achieved on pristine isotropic films without using dopants. When the rigid-rod polymer concentration exceeded 25 wt %, the isotropic solution could be transformed into a liquid-crystalline solution that allowed deformations to be applied to produce anisotropic films. Significant increase in σ was obtained in a sheared film along both the parallel direction (∥) and the transverse direction (⊥) with a σ∥/σ⊥ = 5. Additionally, enhanced σ was realized in films heat-treated at about 100°C, in the derivatized polymer with higher molecular weight from dialysis, and in substituting the sulfonated ion Na+ by H+ in the pendants of the polymers. Constant-voltage measurements were applied to the polymers to monitor the σ stability for ascertaining the nature of the conductivity. No electronic contribution in σ was detected. Instead, a monotonically decreasing σ was consistently observed indicative of ionic conductivity. © 1993 John Wiley & Sons, Inc.
    Additional Material: 6 Ill.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1002/polb.1993.090311306
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