Cupra rayon

Cupro/viscose/modal/deacetylated acetate Cupra/rayon... 

Q mercerized cotton and ramie. (The data of regenerated cellulose samples except for cupra rayon fibers were reproduced from Ref. 1 ... 

Figure 9 Schematic structure models of native cellulose and cupra rayon fibers-...

Figure 9 CP/MAS C NMR spectra of the crystalline components of cupra rayon with the water contents of 0% (a) and 155% (b). (Reproduced from Ref.4. Copyright 1985 Academia Republicii Soclaliste Romania.)...

Figure 11 shows the spectra of the noncrystalline components of rayon fibers with the water contents of 0% and 158%( ). In contrast to the case of cotton, the linewidths of the respective resonances do not remarkably decrease by the addition of water for examples, the half-value width of the Cl resonance line is 205 Hz for the hydrated sample, whereas it is 256 Hz for the dry sample. As pointed out above, this fact implies that the molecular mobility of the noncrystalline chains does not greatly increase with the increase of water content. Moreover, the noncrystalline component of rayon does not undergo such a significant change of distributions in torsion angles 4> vjj as observed for cotton cellulose, possibly because the molecular conformation of this component is rather random in the dry state. In other words, such a disordered conformation may hardly allow marked distortion of the noncrystalline chains to be produced upon drying cupra rayon. 

Fig. 16. Integrated fraction of the downfield component of the C4 resonance line versus degree of crystallinity, /, determined by X-ray analysis., Native cellulose O, regenerated cellulose , mercerized cotton and ramie. (The data for regenerated cellulose samples, except for cupra rayon fibres, were reproduced from ref. 45).

Native cellulose Valonia Bacterial Cotton Ramie Regenerated cellulose Cupra rayon Amorphous... 

Soluble cupra and viscose rayons, acetate, Amel, silk and nylon. 

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