Vulcanized cotton

Vulcanized cotton + oil Cotton + starch and/ or clay Cotton + starch or sizing Cotton + resin... 

Piperidines. A significant use of piperidine (18) has been ia the manufacture of vulcanization accelerators, eg, thiuram disulfide [120-54-7] (115) (see Rubber chemicals). Mepiquat dichloride [24307-26-4] the dimethyl quaternary salt of (18), is used as a plant growth regulator for cotton (qv). Piperidine is used to make vasodilators such as dipyridamole [58-32-2] (116) and minoxidil [38304-91-5] (117), and diuretics such as etozoline [73-09-6] (118). 

In most cases the pigments used are also required to be migration-resistant. The suitability test is also carried out with 5 different pigment concentrations. To test the fastness to bleeding, the unvulcanized colorations are brought into defined contact with a white milled sheet of specific composition and vulcanized wet for 20 minutes in open steam at 140°C. During this process, half the coloration is often covered with a wet cotton cloth to determine whether the cloth, the rubber or both are stained by bleeding. 

Before 1800 Cotton, flax, wool, and silk fibers bitumens caulking materials glass and hydraulic cements leather and cellulose sheet (paper) natural rubber Hevea brasiliensis), gutta percha, balata, and shellac 1839 Vulcanization of rubber (Charles Goodyear)... 

In 1845, as vulcanized rubber was becoming popular, the Swiss chemistry professor Christian Schobein wiped up a spilled mixture of nitric and sulfuric acids with a cotton rag that he then hung up to dry. Within a few minutes, the rag burst into flames and then vanished, leaving only a tiny bit of ash. Schobein had discovered nitrocellulose, in which most of the hydroxyl groups in cellulose are... 

As with any scientific endeavor, chance discovery played an important role in the development of polymers. In all cases, however, there was a scientist with an open and innovative mind who was ready to recognize and take advantage of a chance observation. Charles Goodyear accidentally tipped sulfur into heated natural rubber to discover vulcanized rubber. Christian Schobein inadvertently wiped up a nitric acid spill with a cotton rag to discover nitrocellulose. Jaques Brandenberger thought of cellophane as he observed the accidental stains on tablecloths. Also, as was discussed in Chapter 1, Teflon was discovered upon the unexpected disappearance of a chemical in a gas cylinder that Roy Plunkett was compelled to saw in half. 

Coated abrasives consist of a flexible backing on which films of adhesive hold a coating of abrasive grains. The backing may be paper, cloth, open-mesh cloth, vulcanized fiber (a specially treated cotton rag base paper), or any combination of these materials. The abrasives most generally used are fused aluminum oxide, sol-gel alumina, alnmina-zirconia. silicon carbide, garnet, emeiy, and flint. 

As a matter of fact, mankind knows polymers from ancient times, due to the existence of naturally occurring polymers such as latex, starches, cotton, wool, leather, silk, amber, proteins, enzymes, starches, cellulose, lignin, and others. The other type of polymers are synthetic polymers. Braconnot, in 1811, perhaps made the first significant contribution to polymer science by developing compounds derived from cellulose. Later, cellulose nitrate was obtained in 1846 by Schonbein, afterward in 1872, its industrial production was established. Besides, in 1839, Goodyear found out by accident that by heating latex with sulfur its properties were altered creating a flexible and temperature-stable rubber. This process is named vulcanization. 

The facepiece of this m.special rubber comptiund. The out-side surface was covei ed by a layer of thin cotton fabric caljed stockinette which was vulcanized to the rubber. The facepiece material Fio. no.—Americnn A.T- (Akron-Tii ot) with stockinette covering was manu-... 

Use In the manufacture of paper, vulcanized fiber, mercerized cotton, viscose rayon. 

An efficient method of reclaiming vulcanized scrap was developed about 1900, involving digestion of the scrap with NaOH plus a hydrocarbon softener. This separated the cotton insertions from the rubber and partially reversed the effect of vulcanization. Use of reclaim has long been an important adjunct to the industry, especially for low-cost, high-volume products. 

USE In the manufacture of furfural-phenol plastics such as Durite in solvent refining of petroleum oils in the prepn of pyromucic acid. As a solvent for nitrated cotton, cellulose acetate, and gums in the manuf of varnishes for accel -crating vulcanization as insecticide, fungicide, germicide as reagent in analytical chemistry. In the synthesis of furan derivatives. Caution Irritates mucous membranes and acts on CNS- Causes lacrimal ion, inflammation of eyes, irritation of throat, headache-... 

OTHER COMMENTS used in dye and dyestuff intermediates for hair, fur, leather, cotton, and synthetics used in accelerating vulcanization, as an antioxidant, and stabilizer used in the preparation of antioxidants for petroleum fuels also used in the preparation of grease thickeners, electrical insulators, and rust removers useful as a catalyst and as an analytical reagent use in preparation of epoxy resins, synthetic fibers, heat-resistant polymers, and coatings for leather, paper, and textiles. 

Celluloses can be converted to other useful products by reorientation of their fiber structure. Paper, parchment paper, vulcan fiber, mercerized cotton, and hydrocelluloses belong in this class. 

Vulcanized fiber n. (1) Resin-firee cellulosic plastic. Made by immersing cotton waterleaf paper in a solution of zinc chloride, applying slight heat and pressure and subsequently... 

Base paper of vulcanized fiber is absorbent, voluminous paper made from cotton rags, cotton linters, and refined pulps. 

Common elastomeric bearings are made of elastomer, i.e., either natural or synthetic rubber (e.g., neoprene), which is flexible in shear (low GA) but very stiff against volumetric change. To avoid bulging (lateral expansion that adversely affects the properties of the elastomer) different types of reinforcement are used in the elastomer (fiberglass, cotton, steel). The most common and efficient (and also the most expensive) type of reinforced elastomeric bearings is that reinforced with thin steel plates as shown in Fig. 15 these are constmcted by vulcanizing elastomer to these steel plates. 

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