Oxidation damage nylon

The major effects of air pollution on fabrics are soiling and loss of tensile strength. Sulfur oxides are considered to cause the greatest loss of tensile strength. The most widely publicized example of this type of problem has been damage to women s nylon hose by air pollution, described in newspaper accounts. The mechanism is not understood, but it is postulated that fine droplets of sulfuric acid aerosol deposit on the very thin nylon... 

It is difficult to find any definitive information that indicates ozone damage as extensive as that suggested in the mri report. The latter identified cotton, nylon, and rayon as particularly susceptible to ozone. The oxidation of cellulose fibers by ozone was the subject of a study in 1952 that showed that dry cotton was not seriously degraded by ambient ozone. In more recent studies, these conclusions were confirmed. The only information available on fibers other than cotton addressed the effect of ozone on modacrylic, acrylic. Nylon 66, and polyester fabrics.The results indicated minimal effects on these fibers. 

The mechanism of degradation is the loss of polymer cross-linking. This results in the membrane polymer dissolving, similar to a nylon stocking when exposed to chlorine bleach. Damage is irreversible and will continue as long as the membrane is exposed to the oxidizer. 

The chemical and physical properties of nylons have been extensively described (76). Nylon will not support mildew or bacteria. Moth larvae may bite their way through nylon if imprisoned. In soil burial tests, it was found that nylon 6 retained more than 95% of its strength after six months. By contrast, wool and cotton were rotten after one month (3). Nylon may be affected by chlorine bleach, and strong oxidizing bleaches can damage it (31). 

Photooxidation reactions only take place in the presence of oxygen (15, 17). These reactions are the primary source of most of the sunlight damage to textiles. Photooxidation of nylon and model compounds have shown that oxidative attack usually produces free radicals, peroxides, and ultimately polymer chain scission. This results in lower tensile strength and ultimately a shorter useful lifetime of the textile product. 

Why do we not want O3 in the troposphere Because that is where we Uve—along with all the other plants and animals on Earth Ozone is a powerful oxidizing agent and can be the culprit lurking behind respiratory diseases, deterioration of human-made materials such as rubber and nylon, and damage to crops and other plants. 

Sodium chloride can be easily polished between use. The crystal is sanded flat with a flnegrade sandpaper if it is freshly cleaved, scratched, or damaged by water. Two polishing laps are prepared. There are different types, but the wet lap can be simply two thicknesses of fine nylon cloth stretched over a flat surface. The wet lap is wetted with water and sprinkled with a little fine polishing powder such as aluminum oxide or cerium oxide. This is rubbed smooth and all excess water is wiped off. The flat salt plate is mbbed about 20 strokes on the wet lap and then, without delay, is buffed about 7 strokes on the dry lap, which can be simply a layer of diaper cloth held flat. Cesium bromide... 

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