![]() ![]() ![]() doi: 10.1134/S1070427209040235įink HP, Weigel P, Purz HJ, Ganster J (2001) Structure formation of regenerated cellulose materials from NMMO-solutions. doi: 10.1002/app.28351Įvlampieva NP, Vitz J, Schubert US, Ryumtsev EI (2009) Molecular solutions of cellulose in mixtures of ionic liquids with pyridine. Horwood, Chichester, p 143Įl-Wakil NA, Mohammad LH (2008) Structural changes of regenerated cellulose dissolved in FeTNa, NaOH/thiourea, and NMMO systems. In: Kennedy Ellis (ed) Cellulose and its derivatives, 1st edn. Testing method of degree of polymerization of ramie celluloseĬosgrove JD, Head BC, Graham SG, Warwicker JO, Lewis TJ (1985) A GPC study of cellulose degradation. This work provided a simple, accurate and reliable method for determining and the molecular weight of cellulose.Ĭael JJ, Cannon RE, Diggs AO (1981) Cellulose/viscosity molecular weight relationships by GPC LALLS. The uncertainty of this relationship was estimated to be 5 %. As a result, a relationship DP = 134 1.2 was built, suitable for DPs in the range of 220–1400. Then the molecular weight and its distribution of representative samples were cross-checked by gel permeation chromatography for soluble derivatives of cellulose. The degree of polymerization (DP) of these cellulose samples was determined by Copper (II) ethylenediamine method. The values obtained by these two methods were well consistent. of solutions of nine cellulose samples was measured by using rheometer with cylinder fixture and Ubbelohde viscometer, respectively. These advantages make it as an ideal solvent system to build a new characteristic method of cellulose’s molecular weight by the measurement of the intrinsic viscosity, which is significantly better than the currently used solvent systems. During the dissolution process no degradation of cellulose was observed, and all the resultant cellulose/BmimAc/DMSO solutions were transparent and stable. For simply and accurately determining molecular weight of cellulose, an ionic liquid mixed with a co-solvent, 1-butyl-3-methylimidazolium acetate/dimethyl sulfoxide (BmimAc/DMSO) (1:1, w/w) was used and dissolved cellulose well at ambient temperature. ![]()
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