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Light scattering study of an aromatic polyamide‐hydrazide polymer

1979; Wiley; Volume: 17; Issue: 12 Linguagem: Inglês

10.1002/pol.1979.180171204

1542-9385

E. Bianchi, A. Ciferri, A. Tealdi, W. R. Krigbaum,

Polymer Nanocomposites and Properties

Abstract The aromatic Polyamide‐hydrazide, Monsanto X‐500, has been studied by light scattering in dimethyl sulfoxide, a thermodynamically good solvent. The unperturbed dimensions, (〈 r 〉 av / M ) 1/2 = 1.93 × 10 −8 at 25°C., indicate a rather highly extended chain. The persistence length falls in the range 35–63 Å, which corresponds to a length of between two and four formula units. This is considerably smaller than the values which have been reported for the aromatic polyamides, poly( p ‐benzamide) and poly( p ‐phenylene terephthalamide). X‐500 appears to approximate coil‐like behavior at a molecular weight of 45,000. Theoretical predictions, based upon the 〈 r 〉 av / bL ratio, are compared with the observation that no evidence for an anisotropic phase has been found in X‐500 solutions in dimethyl sulfoxide at polymer volume ranging from 0.12 to 0.19 (depending upon the concentration of added LiCl).