Application of fragrance microcapsules onto cotton fabric after treatment with oxygen and nitrogen plasma

Cotton fabric was exposed to low-pressure capacitively coupled plasma to enhance the adsorption and adhesion of fragrance microcapsules (FCM). Two plasma-forming gases, namely oxygen (O$_2$) and nitrogen (N$_2$), were investigated. The untreated and plasma-treated samples were investigated for their morphological changes by scanning electron microscopy (SEM), mechanical properties (breaking force, elongation, and flexural rigidity), and wicking properties. The cotton samples were functionalized with FCM and the effect of plasma pretreatment on the adsorption and adhesion of FCM was evaluated using SEM, air permeability, fragrance intensity of unwashed and washed cotton fabrics, and Fourier transform infrared spectroscopy (FTIR). The results show that the plasma containing either of the two gases increased the wicking of the cotton fabric and that the O$_2$ plasma caused a slight etching of the fibers, which increased the tensile strength of the cotton fabric. Both plasma gases caused changes that allowed higher adsorption of FCM. However, the adhesion of FCM was higher on the cotton treated with N$_2$ plasma, as evidenced by a strong fragrance of the functionalized fabric after repeated washing.