35—THE DEGREE OF POLYMERIZATION AND ITS DISTRIBUTION IN CELLULOSE RAYONS. Part VI. THE RELATION BETWEEN THE INTRINSIC VISCOSITY AND DEGREE OF POLYMERIZATION OF CELLULOSE NITRATE

The relation between the intrinsic viscosity in n-butyl acetate and acetone and the degree of polymerization (DP) has been deduced for cellulose nitrate fractions with degrees of polymerization in the range 100—1800 and nitrogen contents greater than 12%. Cellulose trinitrates that had been fractionated three or four times were used, and degrees of polymerization were determined osmotically. A comparison of sedimentation (diffusion) and osmotic data for three nitrate fractions and seven fractions of cellulose acetate confirms that the fractions were reasonably homogeneous and justifies the relation of intrinsic viscosity to a number-average DP. The data from previous papers in this field have been recalculated in a critical manner and the results compared with those of the present investigation.