Effect of SO₂, NO₂ and O₃ Gases That are Different Kinds of Density on Physical Properties of Fiber and on the Fastness of Change in Color of Dyed Materials (Part 1)

On the Case of High Density SO₂ and NO₂

Abstract

In order to know the effects of polluting gases on the physical properties of the fiber and on the color fastness, the experiments were carried out in the presense of dry SO₂ and dry NO₂ gases without daylight and the following results were obtained :
1) The tensile strength of the acrylic and polyester fibers showed a little change in the presense of SO₂ (1, 000 ppm) and NO₂ (1, 000 ppm) gases after 95 days of exposure, but for silk, nylon and Vinylon the tenacity and the elongation showed remarkable changes.
2) The elongation of the rayon and the acetate increased with the exposing time.
3) The solubility of the exposed wool and silk in 0.5 % aq. NaOH decreased with the exposing time.
4) The colors of the dyed samples were changed especially by the presense of NO₂ gas and a great deal of change were observed for blue colored samples. Their tensile strength also decreased very much along with the change in color.