The porous structure of cellulose gel regenerated from calcium thiocyanate solution

doi:10.1016/0021-9797(80)90311-2

Journal of Colloid and Interface Science

Volume 77, Issue 2, October 1980, Pages 413-417

https://doi.org/10.1016/0021-9797(80)90311-2 Get rights and content

Abstract

Three celluloses of various degree of polymerization (DP, 180, 770 and 1620; viscosity average) were dissolved into 59 wt% calcium thiocyanate aqueous solution at 1.0 wt% cellulose concentration. Cellulose was regenerated from the solution in a form of gel by extracting the salt with methanol. This cellulose gel was not chemically decomposed significantly except that its DP decreased to about 500 for the latter two samples (original DP 770 and 1620). The mean pore size of the cellulose gels was estimated by hydraulic measurement to be 1500–2300 Å, depending on the original DP. Extent of shrinkage of the gels on regeneration was greater for those prepared from the celluloses of higher DP, which resulted in lower water content and smaller mean pore size. BET surface area and pore size distribution of the solvent-exchange-dried samples of the cellulose gel were calculated from nitrogen adsorption isotherm. The results revealed the characteristic porous structure of the gel with large pore volume in the range of pore diameter of several hundred to several thousand angstroms. Possible uses of this remarkable substance as filter or chromatographic column packing are suggested.

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The porous structure of cellulose gel regenerated from calcium thiocyanate solution

Abstract

Hoppe-Seyler's Z. Physiol. Chem.

J. Soc. Chem. Ind.

Kolloid Z.