Method for modifying polyester by swelling agent combined with cutinase

A method for increasing hydrophilicity of polyester fibers, which comprises:

• a) mixing a swelling agent of phenol solution or an o-vanillin solution with the polyester fibers at a temperature of 90° C. to 120° C. for about 3 to 5 hours to produce swollen polyester fibers, and
• b) adding a Humicola insolens cutinase solution comprising 100 U/mL cutinase at a pH of 8 to the swollen polyester fibers at a temperature of about 60° C. for about 24 hours, thereby increasing hydrophilicity of the polyester,
• wherein increasing the hydrophilicity of the polyester fibers is measured by release of hydrolysates comprising terephthalic acid (TPA) and mono (2-hydroxyethyl) terephthalate (MHET) during cutinase treatment and comprises catalyzing hydrolysis of ester bonds in the swollen polyester fibers to increase an amount of hydrophilic groups on the swollen polyester fibers, and
• wherein the amount of TPA and MHET released by the swollen polyester fibers is increased by 51.7% to 67.5% as compared with polyester fibers not treated with the phenol solution or o-vanillin solution.