Waterproof fabric

Water Repellency and Water Resistance. Water repeUency is defined as the abihty of a textile fiber, yam, or fabric to resist wetting, whereas water resistance is a general term appHed to a fabric s abiUty to resist wetting and penetration by water (2). A third term, waterproof, is appHed to those fabrics that do not allow any water penetration at all. Waterproof fabrics are generally coated with an impermeable surface layer that does not allow air permeabihty. Water-repellent finishes are hydrophobic compounds that are appHed to fabrics to inhibit water penetration while still allowing air permeabihty. 

Designing effective water-repellent, water-resistant, or waterproof fabrics to provide protection in inclement weather or during certain outdoor activities requires an understanding of the chemical and physical properties of water. Whether you are sailing in wind-driven rain, hiking in a downpour, or sitting on a wet surface, chemistry can keep you dry ... 

The use of rubber for sports balls and for waterproofing fabric had been noted by Christopher Columbus in his voyages to America, but the results had not been satisfactory (Asimov 1989). Natural rubber is a polymer of the isoprene molecule (CsHs) with molecular weight in the order of 200,000, and consists of thousands of chains with short side chains. 

Eluoropolymers are able to withstand moderately high temperatures and are one of the slipperiest known solids. As a result, Teflon is commonly used as a nonstick coating, as a shell for bullets, and as an ingredient in waterproof fabrics. 

Possess both hydrophobic and hydrophilic properties, which makes them useful in waterproofing fabrics and in biological applications, such as surgical and cosmetic implants... 

Use Dyeing mordant, water purification, waterproofing fabrics, manufacture of lakes, filtering medium, chemicals (aluminum salts), lubricating compositions, manufacture of glass, sizing paper, ceramic glaze, antacid. 

Use Hydroxystearic acid, waterproofing fabrics, cosmetics, lubricant, mold-release agent, candles, carbon paper. 

Write the formulas that correspond to the following names (a) aluminum oxide (used to waterproof fabrics), (b) cobalt(III) fluoride (used to add fluorine atoms to compounds), (c) iron(II) sulfate (in enriched flour), (d) ammonium hydrogen phosphate (coats vegetation to retard forest flres), and (e) potassium bicarbonate (in Are extinguishers). 

Corn is a valuable source of industrial chemicals. For example, furfural is prepared from corncobs. It is an important reactant in plastics manufacturing and a key solvent for the production of cellulose acetate, which is used to make everything from videotape to waterproof fabric. It can be reduced to furfuryl alcohol or oxidized to 2-furoic acid. 

USE Substitute for beeswax for making candles, wax figures for waxed paper and cloth in polishes, electrical insulators waterproofing fabrics for bottles for hydrofluoric acid in dentistry for impression and inlay waxes and modeling compounds. 

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