Shrinkproofing Of Wool With Polyglycine From The Polymerization Of Thiazolid-2:5-Dione
Shrinkproofing of wool with thiazolid-2: 5-dione is not possible from aqueous solution but can be obtained from a range of organic solvents of low water affinity at tempera tures > 40°. The abrasion resistance of treated fabric is about 1.5-2 times that of untreated fabric but cost of treatment would be prohibitive in practice. Since the poly merization of dione is initiated by water in the wool, the polyglycine (number average degree, of polymerization about 18) cannot be attached by covalent bonds but by inter molecular hydrogen bonds. Descaling shows that most of the polyglycine is located in the scales a thin surface layer can be seen under the electron microscope. This surface layer reduces the directional frictional effect and produces shrinkproofing with a weight increase of the fiber of only 1%. It is most unlikely that spot welding of fibers with polyglycine is a contributing factor towards, shrinkproofing.