Preparation of fatty acid-amino diol condensate and its utilization as a durable nonionic softener for PAN fabrics.

Polyacrylonitrile (PAN) fabrics meet the customers' requirements in many aspects. Nevertheless, PAN fabrics suffer from low moisture regain and the accumulation of electrostatic charges on the fabric surface. Some PAN products exhibit rough a surface which is uncomfortable for human skin. Herein, we synthesized a new hydrophilic nonionic softener by reacting a fatty acid (FA), extracted from wool wax, with 2-amino-2-methyl-1,3-propanediol (AMPD). Adopting the pad-dry-cure technique, the synthesized softener was chemically bound to pretreated PAN fabrics. Without deterioration of the fabrics' mechanical properties, new functions have been imparted to the treated PAN fabrics, viz., silk-like hand, induced resistance to the accumulation of electrostatic charges, and improved wettability. Fourier-transform infrared (FTIR) spectroscopy and carbon-13 nuclear magnetic resonance (C-NMR) were utilized for the structure elucidation of the prepared softener as well as to determine whether AMPD reacts with the fatty acid through its amino or hydroxyl group. The mechanism of the preparation of the softener as well as its mode of action on PAN fabrics were proposed. The effects of the applied softener on air and water permeability, ultraviolet protection factor (UPF), stiffness, tensile properties, and yellowness of the treated fabric were studied. The scanning electron micrographs of the treated fabric revealed the existence of a layer of the applied softener on the fabric surface. The finished fabric was found to be durable against washing for up to 20 cycles in terms of the fabric smoothness and durability.