Cadoxen

Several solvents, such as cupriethylenediamine (cuen) hydroxide [111274-71 -6] depend on the formation of metal—ion complexes with ceUulose. Although not as widespread in use as the viscose process, cuen and its relatives with different metals and ammonium hydroxide find substantial industrial use (87). The cadmium complex Cadoxen is the solvent of choice in laboratory work (91). 

Tri-ethylene diamine cadmium hydroxide [Cd(en)3](OH)2 Cadoxen and Cden3) Good solvating properties, slight oxidative degradation, clear, stable and colourless... 

Proposed as a further abbreviation of cadoxen, analogous to Cuen. 

I) are unusually large. Recalculation of the data by the new procedure gives the results tabulated in Table III. The ratios are now more of the order usually obtained for material of this sort. Also, the values for DP are shifted those for DPW are lowered to the range of the Cadoxen viscosity-DP s, while those for DPn are raised. 

Dialysis studies122 of ofellulose and dextran in aqueous solutions of barium hydroxide, sodium hydroxide, and cadoxene (cadmium hydroxide in ethylenediamine) showed no difference in complexing ability between the two polysaccharides. Furthermore, in solutions having equal base normality, Ba2 , Na ,, nd Cd (ethylenediamine) had loughly equal complexing abilities. 

Figure 2. Rate of change of degree of polymerization of H5PO -swollen cellulose by Ct and Cx enzymes of T. koningii cellulose. Residual cellulose was dissolved in Cadoxen (46) and the degree of polymerization determined viscometrically (46).

Figure 11. Effect of Cx enzyme components of T. koningii cellulase on the degree of polymerization of HsPO -swollen cellulose. The degree of polymerization was determined by viscometry after dissolution in Cadoxen...

C with cadoxen as a solvent and a propanol-water(3 1 by volume)... 

At fixed Mw, the values of for curdlan are about one half those for cellulose, indicating that the curdlan molecule assumes a more coiled form than does the cellulose molecule in 1 1 water-diluted cadoxen. 

Table I. Numerical results fran light scattering measurements on curdlan fractions in the 1 1 water-diluted cadoxen at 25°C(4)...

W. Archwal, A. Narkar Die Bestimmung optischer Aufheller auf Baumwolle mit-tels Cadoxen als Losungsmittel , Textilveredlungl (1972) no. 1, 19-24. 

Cadoxen method Direct detection of double bond UV [145]... 

Henley, D. The cellulose solvent cadoxen, a preparation and a viscometric relationship with cupriethylene diamine. Svensk Papperstidn. 63, 143 (1960). 

The polymer properties of cellulose are usually studied in solution, using solvents, such as CED or Cadoxen (see Section 9.2). On the basis of the solution properties, conclusions can be drawn concerning the average molecular weight, polydispersity, and chain configuration. However, the... 

Sjostrom, E., and Enstrom, B. (1966). Spectophotometric determination of the residual lignin in pulp after dissolution in cadoxen. Sven. Papperstidn. 69, 469-476. 

Cadoxen [Cd(en)3](OH)2 Colorless, useful for optical measurements. Cellulose shows good stability in this solvent. 

Fig. 38. Correlation between the unperturbed Benoit-Doty persistence length and the persistence length q L 671 A, cellulose/cadoxen A cellulose/FeTNa O CA(2.92)/DMAc (J) CA(2.46)/DMAc —O CA(2.46)/acetone <> CA(2.46)/THF CA(0.49)/DMAc O ...

Measured in acetyl bromide b Measured in cadoxene c Measured in dioxane d Corrected for carbohydrates L Measured as suspension in methyl cellosolve 1 Calculation based on Klason lignin content of material 8 Variation from average, 4 5% h Absorptivity at 205 nm... 

Schoning AG, Johansson G (1965) Absorptiometric determination of acid-soluble lignin in semichemical bisulfite pulps and in some woods and plants Sven Papperstidn 68 607-613 Schultz TP, Templeteon MC, McGinnis GD (1985) Rapid determination of lignocellulose by diffuse reflectance Fourier transform infrared spectrometry Anal Chem 57 2867- 2869 Sjostrom E, Enstrom B (1966) Spectrophotometnc determination of the residual lignin in pulp after dissolution in cadoxene Sven Papperstidn 69 469-476... 

---