kidney element and then circulating through the fiber lumen a methanolic sodium hydroxide solution a satisfactory solution has been found to be 0 1 m this solution is circulated for about a half an hour about 20 glycerine may be added to this solution to prevent the fiber from shrinking as a result of the hydrolysis the sodium hydroxide serves as the hydrolyzing agent while the methanol serves to leach out the oligosaccharide ester of course the hydrolysis and leaching step may be conducted separately if desired the fiber is then washed successively with isopropyl alcohol containing acetic acid and glycerine and then finally washed with isopropyl alcohol containing glycerine and blown dry the invention encompasses both the process and the product and the scope of the invention is not limited to the following examples which are given as illustration only table i__________________________________________________________________________ plasticizer or tensile strength tensile modulusfiber type extender psi u00d7 10 sup 4 psi u00d7 10 sup 5 __________________________________________________________________________cellulose vs cellulose acetate 1 cupraphan u00ae cellulose 3 04 u00b1 0 10 7 85 u00b1 1 88 1a cordis dow u02dc 0 03 u02dc 2 60 2 celluloseacetate run 93 no saib 3 00 u00b1 0 29 6 53 u00b1 0 82plasticizers vs saib extender 3 celluloseacetate 16 carbowax u00ae 400 1 49 3 58 4 celluloseacetate 16 carbowax u00ae 600 0 93 3 14 5 celluloseacetate 16 triacetin 2 25 5 78 6 celluloseacetate 16 saib 2 69 6 26 sucrose acetate iso butyrate __________________________________________________________________________ examples 1 and 1a represent cuprophan and cordis dow dialysis fibers respectively.