Dynamic birefringence and rigidity of poly-p-benzamide molecules in solutions

Tsvetkov, V.N.; Kudryavtsev, G. I.; Shtennikova, I.N.; Peker, T.V.; Zakharova, E.N.; Kalmykova, V.D.; Volokhina, A. V.

doi:10.1016/0014-3057(76)90008-2

Cited by 23 publications

(3 citation statements)

References 2 publications

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“…[5][6][7][8][9][10][11][12][13][14][15][16] The q values are tabulated in Table I. Diffusion and sedimentation experiments appear not to be suffi- Table I Persistence Length (q) in Á, Measured in 96% Sulfuric Acid technique (ref) p-BA p-PT light scattering, Rg (5) 400 200 light-scattering depolarization ratio (6) 150 flow birefringence (7) 185 light scattering (8) 600 200 viscosity (8) 400 150 flow birefringence (9) 325 light-scattering depolarization (10) 287 electric birefringence, Kerr effect (11) 300 light scattering (12) >450 flow birefringence (13) 1000 flow birefringence (14) 650 flow birefringence (15) 1050 650 flow birefringence (16) 435 275 ciently sensitive to yield even a rough estimate of g. 15,17,18 Changes in the nature and strength of the solvent acid, manifested by variations in the protonation level of the amide groups along the chain and in the consequential changes in chain extension and rigidity, were also reported to affect the exponent o,19,20 the persistence length q,18 and the radius of gyration Bg. 19 Plots by Arpin and Strazielle5,8 of intrinsic viscosity and radius of gyration against weight-average molecular weight (Mw) show the same dependencies and the same data scatter for unfractionated as for fractionated p-PT.…”

Section: Introductionmentioning

confidence: 99%

Depolarization ratios and rigidity of aromatic polyamides

Zero¹,

Aharoni²

1987

Macromolecules

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Monodisperse oligomers and several unfractionated polymers of poly(p-benzanilide-terephthalamide) (p-BT) were prepared and characterized. Their depolarization ratios were measured in concentrated (96%) sulfuric acid and they produced optical anisotropy values essentially the same as those of poly(p-phenylene terephthalamide) (p-PT) of comparable Mw. A numerical fit to our p-BT data and literature data for fractionated p-PT yielded a persistence length of 113 Á. The unfractionated p-PT, particularly at high molecular weights, tended to yield higher depolarization ratios and, consequently, higher persistence lengths than equivalent fractionated material, possibly due to high polydispersity.

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Section: Introductionmentioning

confidence: 99%

Depolarization ratios and rigidity of aromatic polyamides

Zero¹,

Aharoni²

1987

Macromolecules

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“…Therefore, Mark–Houwink equations for polyaniline should involve polymers similar to polyaniline with an amide group attached to the chain that can be dissolved in sulfuric acid. Four such polymers were found in the literature: nylon‐6,20, 43 nylon‐12,44 poly( p ‐phenylene terephthalamide) (PPTA),20, 45 and poly( p ‐benzamide) 46. Nylon‐6 and nylon‐12 have alkyd chains attached to the amide,43, 44 whereas PPTA and poly( p ‐benzamide) have a p ‐phenylene aromatic group attached to the amide group 45, 46.…”

Section: Theorymentioning

confidence: 99%

“…Four such polymers were found in the literature: nylon‐6,20, 43 nylon‐12,44 poly( p ‐phenylene terephthalamide) (PPTA),20, 45 and poly( p ‐benzamide) 46. Nylon‐6 and nylon‐12 have alkyd chains attached to the amide,43, 44 whereas PPTA and poly( p ‐benzamide) have a p ‐phenylene aromatic group attached to the amide group 45, 46. The shape or rigidity of the polyaniline chain in sulfuric acid is unknown; therefore, PPTA was chosen as a model because both PPTA and polyaniline have the p ‐phenylene aromatic group.…”

Section: Theorymentioning

confidence: 99%

Stability of polyaniline in air and acidic water

Hobaica

2003

J Polym Sci B Polym Phys

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Polyaniline is a member of the class of electrically conducting polymers, having possible commercial applications such as coatings. Aqueous-based polyaniline coatings are preferred over organic solvent or concentrated strong acid based coatings because water is not a pollutant. The overall goal of this study was to further the development of water-based polyaniline coatings by an examination of the effect of acidic water (pH 1.18) and air on polyaniline. Knowledge of the effect of water on the structure, molecular weight, electrical conductivity, and diffusion of the dopant assisted in ascertaining whether polyaniline degraded with water exposure. Knowledge of how Fourier transform infrared (FTIR) spectra would be affected by dry air was important for determining if polyaniline was chemically stable with time. The results showed that the molecular weight, ultraviolet-visible and FTIR spectra, and carbon-to-nitrogen molar ratio in the polymer backbone all remained unchanged during acidic water immersion. The constant nature of these physical parameters showed a high degree of water stability. A chloride ion diffusion coefficient of 2.8 to 85 ϫ 10 Ϫ9 cm 2 /h, the chloride concentration, and the electrical conductivity were also measured with the water immersion time. Aging polyaniline powders in a desiccator for 5 years showed no effect on the molecular structure, as indicated by the FTIR spectrum.

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Viscosity – Molecular Weight Relationships and Unperturbed Dimensions of Linear Chain Molecules

Kurata

Tsunashima

1999

The Wiley Database of Polymer Properties

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Dynamic birefringence and rigidity of poly-p-benzamide molecules in solutions

Cited by 23 publications

References 2 publications

Depolarization ratios and rigidity of aromatic polyamides

Depolarization ratios and rigidity of aromatic polyamides

Stability of polyaniline in air and acidic water

Viscosity – Molecular Weight Relationships and Unperturbed Dimensions of Linear Chain Molecules

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