Full Description
This method describes the measurement of the fluidity of dispersions of textile cellulose in cuprammonium hydroxide solution, to determine the extent to which the cellulose may have been degraded chemically. It is applicable to cotton that has received a scouring treatment and to regenerated cellulose rayons.
Note 1: The techniques specified in this method are substantially those described in "The Viscosity of Cellulose Solutions" of the Fabric Resarch Committee of the Department of Scientific and Industrial Resarch, Great Britain (published 1932 by His Majesty's Stationery Office, London). They were originally developped in the laboratories of the British Cotton Industries Research Association (Shirley Institute) and, for a full discussion of the method, reference may be made to the article by Clibbens and Little, J. Textile Institute, 27, T285 (1936)
Note 2: For scoured or bleached cotton, the fluidity as measured by this method may range from 20 (Pa.s)^-1, where the cotton has suffered no chemical attack, to approximately 400 (Pa.s)^-1, where the degree of chemical attack has been sufficient to cause total loss of fibre strength. With regenerated cellulose rayons, the lower limit of fluidity where no chemical attack has occured is approximately 50 to 70 (Pa.s)^-1 for high-tenacity rayon or approximately 90 (Pa.s)^-1 for normal-tenacity rayon, the upper limit being as for chemically damaged cotton.
When this method is applied to raw cotton or to other forms of textile cellulose of natural origin containing appreciable amounts of noncellulosic materials, the presence of the latter may interfere with the complete dispersal of the fibre in the reagent.
In all cases, the extent to which the fibre may carry noncellulosic components shall be considered and appropriate steps shall be taken to remove them prior to the fluidity measurement.
Owing to the limited solubility in cuprammonium of cellulosic fibres carrying synthetic resin finishes, this method is not suitable for use with such fibres unless the resin is first removed (CAN/CGSB-4.2 No. 15-M). Since the acid treatment may degrade the cellulose, a control consisting of the same cellulosic fibre but without the resin should be subjected to the same acid treatment, and the effect of this treatment, as determined by fluidity measurements, established.
This method may require the use of materials and or equipment that could be hazardous. This document does not purport to address all the safety aspects associated with its use. Anyone using this method has the responsibility to consult the appropriate authorities and to establish appropriate health and safety practices in conjunction with any existing applicable regulatory requirements prior to its use.
Time-dated standard
