Improvement of crease resistance of cotton fabric by the grafting with acrylic acid and aftertreatment with tris (1-aziridinyl) phosphine oxide

Crease recovery of cotton fabric grafted with acrylic acid and further treated with tris (_??_-aziridinyl) phosphine oxide (APO) was studied with a view of preventing the decrease of tensile strength accompanied with crosslinking.Although the chemical structure of reaction products of APO with acrylic acid grafted cotton is more complicated owing to the presence of the carboxyl groups in the grafted polyacrylic acid than that of the reaction products of APO with ungrafted cotton, APO seems to react not only with hydroxyl groups in the cotton cellulose, as observed for the ungrafted cotton, but also with carboxyl groups in the grafted cotton fabric.Crease recoveries of ungrafted and grafted cotton fabrics in both conditioned and wet states are much improved by treating with APO solution containing 2.5% zinc fluoroborate catalyst. Considerable crease-proofing effect is also observed when the grafted cotton fabrics are treated with APO solution without zinc fluoroborate catalyst, and the decrease in the warp tensile strength is prevented by this treatment. This method is particularly favorable to obtain a good crease recovery-strength relationship.