ISSN:
0887-6266
Keywords:
molecular structure
;
poly (p-hydroxybenzoic acid)
;
x-ray diffraction
;
Chemistry
;
Polymer and Materials Science
Source:
Wiley InterScience Backfile Collection 1832-2000
Topics:
Chemistry and Pharmacology
,
Physics
Notes:
The molecular structure of poly (p-hydroxybenzoic acid) (C6H4COO)x at ambient temperature was determined by x-ray powder diffraction analysis. The diffraction pattern is explained as a mixture of two orthorhombic phases having the same space group Pbc21 with four C6H4COO chemical repeats in the unit cell and the following cell parameters: a = 7.42 Å, b = 5.70 Å, and c = 12.45 Å for phase I (ρcalc = 1.51 g cm-3); and a = 3.83 Å, b = 11.16 Å, and c = 12.56 Å for phase II (ρcalc = 1.48 g cm-3). The chain conformation is the same in both phases, involving two benzoyl rings staggered by ca. 120° along the chain. Disorder has been considered in the packing of phase I by giving equal occupancy to the two molecules oriented up or down along the c chain axis. ©1995 John Wiley & Sons, Inc.
Additional Material:
5 Ill.
Type of Medium:
Electronic Resource
URL:
http://dx.doi.org/10.1002/polb.1995.090330613
