Composition cotton

An all-cellulose group that includes cotton composites... 

Cotton linters or wood pulp are nitrated using mixed acid followed by treatment with hot acidified water, pulping, neutralization, and washing. The finished product is blended for uniformity to a required nitrogen content. The controlling factors in the nitration process are the rates of diffusion of the acid into the fibers and of water out of the fibers, the composition of mixed acid, and the temperature (see Cellulose esters, inorganic esters). 

Specific terms have been designated according to the function and composition of various roUs. Steel roUs that impose pressure, transmit heat, and emboss a pattern onto the fabric are known as pattern roUs. Flexible surface roUs that transport the fabric and permit pressure transmission to the fabric are termed bowl roUs or bowls. Bowl roUs are usually larger in diameter than pattern roUs. The material used to make these types of roUs is chosen according to the depth of surface smoothness to be placed on the fabric being calendered, and must be compatible with the pattern roU. Cellulose pulp, cotton, wool, cotton—wool mixtures, com husk, and various polymer materials are used as fillers for the roU surface compound. 

Textiles. Sorbitol sequesters iron and copper ions in strongly alkaline textile bleaching or scouring solutions (see Textiles). In compositions for conferring permanent wash-and-wear properties on cotton fabrics, sorbitol is a scavenger for unreacted formaldehyde (252) and a plasticizer in sod-resistant and sod-release finishes (253). 

CP esters are generally prepared as the ammonium salt [9038-38-4] by the reaction of cellulose with phosphoric acid and urea at elevated temperatures (130—150°C). The effects of temperature and urea/H PO /cellulose composition on product analysis have been investigated (33). One of the first commercially feasible dameproofing procedures for cotton fabric, the Ban-Flame process (34,35), was based on this chemistry. It consists of mixing cellulose with a mixture of 50% urea, 18% H PO, and 32% water. It is then pressed to remove excess solution, heated to 150—175°C for 5—30 minutes, and thoroughly washed (36). 

When exposed to heat, cotton fabrics, like most substances, increase in temperature to an extent that is proportional to their specific heats. Altering the chemical composition of the fabrics such that large amounts of heat are absorbed and released in repeatable cycles of controllable temperature ranges produces fabrics that are described as temperature adaptable. The process insolubili2es poly(ethylene glycol)s cross-linked with methylolamides in the cotton fabric (78). As with flame-retardant cellulose, attachment is through an ether linkage to the cellulose at a relatively low DS. 

Sodium carboxymethylceUulose, NaCMC, greatly reduces redeposition in cotton-washing systems based on synthetic surfactants. It is effective at remarkably low concentrations of ca 1% of the standard washing compositions used at ca 0.1 to 0.2% in the bath. Thus, ca 0.001—0.002%, or 10—20 ppm NaCMC is sufficient to significantly inhibit redeposition. 

In a study of the adsorption of soap and several synthetic surfactants on a variety of textile fibers, it was found that cotton and nylon adsorbed less surfactant than wool under comparable conditions (59). Among the various surfactants, the cationic types were adsorbed to the greatest extent, whereas nonionic types were adsorbed least. The adsorption of nonionic surfactants decreased with increasing length of the polyoxyethylene chain. When soaps were adsorbed, the fatty acid and the aLkaU behaved more or less independently just as they did when adsorbed on carbon. The adsorption of sodium oleate by cotton has been shown independently to result in the deposition of acid soap (a composition intermediate between the free fatty acid and the sodium salt), if no heavy-metal ions are present in the system (60). In hard water, the adsorbate has large proportions of lime soap. 

Synthetic resins are extensively used, e.g., in surface finishes, in the fabrication and repair of boat and motor vehicle bodies, in the manufacture of laminated boards, for electrical components, in pattern making and in paints and varnishes. Non-rubber adhesives made from fish glues and from cotton derivatives (e.g. cellulose acetate) tend not to be sensitizing but, depending upon composition and the manner of use, many other types may pose significant dermatitic and fume hazards. 

Seventy years ago, nearly all resources for the production of commodities and many technical products were materials derived from natural textiles. Textiles, ropes, canvas, and paper were made of local natural fibers, such as flax and hemp. Some of them are still used today. In 1908, the first composite materials were applied for the fabrication of big quantities of sheets, tubes, and pipes in electrotechnical usage (paper or cotton as reinforcement in sheets made of phenol- or melamine-formaldehyde resins). In 1896, for example, airplane seats and fuel tanks were made of natural fibers with a small content of polymeric binders [1]. 

Climatic conditions, age, and the digestion process influence not only the structure of fibers but also the chemical composition. Mean values of components of plant fibers are shown in Table 4. With the exception of cotton, the components of natural fibers are cellulose, hemi-cellu-lose, lignin, pectin, waxes, and water-soluble substances. 

The mechanical properties of plastics materials may often be considerably enhanced by embedding fibrous materials in the polymer matrix. Whilst such techniques have been applied to thermoplastics the greatest developents have taken place with the thermosetting plastics. The most common reinforcing materials are glass and cotton fibres but many other materials ranging from paper to carbon fibre are used. The fibres normally have moduli of elasticity substantially greater than shown by the resin so that under tensile stress much of the load is borne by the fibre. The modulus of the composite is intermediate to that of the fibre and that of the resin. 

The proposal of multiple crystalline forms in native celluloses implies that all native celluloses are compositions of two distinct forms, which has been earlier indicated for Acetobacter and Vallonia celluloses, 8). From the resolution of the NMR spectra an estimate of about 60-70 % of the la form in Acetobacter cellulose and of 60-70 % of the lb form in cotton was obtained. A further detailed analysis of conformational features in celluloses seemed to need X-ray diffractometric and Raman spectroscopic confirmation 19-56). 

F.16 Cacodyl, which has an intolerable garlicky odor and is used in the manufacture of cacodylic acid, a cotton herbicide, has a mass percentage composition of 22.88% C, 5.76% H, and 71.36% As and a molar mass of 209.96 g-mol. What is the molecular formula of cacodyl ... 

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