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ISSN print edition: 0366-6352
ISSN electronic edition: 1336-9075
Registr. No.: MK SR 9/7
Published monthly
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X-ray study of the supramolecular structure of celluloses III
J. Polčin and F. Valček
Forschungsinstitut für Papier und Cellulose, Bratislava
Abstract: The changes in the cryst. lattice and the lateral order arrangement. (LOA) of bleached cotton, refined sulfate and prehydrolysis kraft pulps were studied by x-ray diffraction measurements. By the action of liquid NH3 (-33.4°), cellulose I and II were transformed into cellulose III, with a 15% decrease in crystallinity. The action of boiling H2O for 1 hr. or of 20° H2O for 24 hrs. on cellulose III results in recrystn. and transformation to cellulose I or IV. By the action of 10% NaOH, cellulose I is transformed only partially, but cellulose III is transformed completely to cellulose II. The measurements of LOD indicate that 18% NaOH causes formation of cellulose II with parameters different from those of cellulose II obtained directly from cellulose I. This type of cellulose is designated as cellulose IIa (I → III → II). The properties of cellulose III indicate that the cryst. lattice is in a metastable state, less stable than cellulose I and II.
Full paper in Portable Document Format: 217a507.pdf (in Slovak)
Chemical Papers 21 (7) 507–516 (1967)
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