Cottons modified

The NH2 groups can be diazotized and reduced in the presence of thiosulphates and different metal ions. The effect of some metal ions, namely Fe ", Sn, Cu +, and Co on the graft yield of cotton modified with aryl diazonium groups via its reaction with 2,4-dichloro-6-(p-nitroaniline)-5-triazine in the presence of alkali and followed by reduction of nitro group was studied [4]. 

Schmidt, A. Bach, E. Schollmeyer, E. Supercritical fluid dyeing of cotton modified with 2,4,6-trichloro-l,3,5-triazine. J. Soc. Dyers Colour. 2003, 119, 31-36. 

Arthur et al.54 have shown that cotton modified by AN grafting retains the structure and appearance of the initial fibre (particularly the transverse cross-section shape) much better if the grafted polymer is located in the surface layer. To this end, they suggest graft polymerization to cotton pre-irradiated in an inert atmosphere and the use of solvents causing no swelling of the fibre. 

The latter method has the advantage of recycling the natural or waste product. Significant examples are cotton modified with amines [3, 4], starch utilized in xanthate form [5, 6, 7], thiol type keratine gel prepared from the wool [8, 9,10], wool simply reduced [11] or modified with amine groups [12, 13, 14] and finally polysaccharides such as cellulose [15, 16, 17], glucose [18] or polyosides [19] modified with thiol or amine groups. 

In attempts to form proteinaceous material with aromatic substituents, a cotton modified chemically to contain aromatic groups was placed in the depolymerization zone, that is, between the external electrodes and an untreated cotton placed downstream in the polymerization zone. The plasma was an equimolar mixture of N2 and H2 that had been shown to be optimal for the production of proteinaceous material when cotton was placed between the electrodes According to ESCA analyses, the nitrogenous films formed downstream were identical whether benzoylated cellulose or benzy-lated cellulose was placed between the electrodes, figure (2) illustrates the spectra obtained with a cotton control (lowest curve) and with a cotton that had been treated in a cold plasma of 1 1 mole ratio of N2 and H2 for one hour while a benzy-lated cotton placed between the electrodes acted as a source of carbon for syntheses of the proteinaceous product (uppermost curve). The middle curve is that for a cotton subjected to the 2 2 plasma in the absence of the benzylated cotton. The Cj g... 

Thermal Decomposition of Cotton Modified by Grafting with Acrylamide and Bis( 8-chloroethyl) Vinylphosphonate... 

Cellulosics. CeUulosic adhesives are obtained by modification of cellulose [9004-34-6] (qv) which comes from cotton linters and wood pulp. Cellulose can be nitrated to provide cellulose nitrate [9004-70-0] which is soluble in organic solvents. When cellulose nitrate is dissolved in amyl acetate [628-63-7] for example, a general purpose solvent-based adhesive which is both waterproof and flexible is formed. Cellulose esterification leads to materials such as cellulose acetate [9004-35-7], which has been used as a pressure-sensitive adhesive tape backing. Cellulose can also be ethoxylated, providing hydroxyethylceUulose which is useful as a thickening agent for poly(vinyl acetate) emulsion adhesives. Etherification leads to materials such as methylceUulose [9004-67-5] which are soluble in water and can be modified with glyceral [56-81-5] to produce adhesives used as wallpaper paste (see Cellulose esters Cellulose ethers). 

The multiplicity of nylon blends, processing systems, and uses requires a large variety of staple types. Tex per filament may be 0.1—2 (1—20 den), the cross section may be round or modified, the luster may be bright or dull, crimp may be present or absent, and the fiber may be heat-set or not, depending on its use. The staple length is about 4 cm for cotton system processing, 5—7 cm for the woolen system, 8—10 cm for the worsted system, and about 18—20 cm for carpet staple. 

Another fire-related problem that has seen some research effort is that of smolder resistance of upholstery and bedding fabrics. Finishing techniques have been developed to make cotton smolder-resistant (152—156), but the use of synthetic barrier fabrics appears to provide a degree of protection. Work also has provided a means of producing cotton fabrics that have both smooth-dry and flame-retardant performance (150,151). In this case, the appHcation of FR treatment should be performed first, and DP treatment should be modified to accommodate the presence of the FR polymer on the fabric. 

Comfort has been a merchandising point for cotton and much of cotton s success has stemmed from this property (159—162). This has not, however, prevented cotton interests from trying to modify the moisture regain or content of finished fabrics (163—165). One unique finish imparts... 

A number of after-treatments with polyester copolymers carried out after sodium hydroxide processing are reported to produce a more hydrophilic polyester fabric (197). Likewise, the addition of a modified cellulose ether has improved water absorbency (198). Other treatments used on cotton and blends are also effective on 100% polyester fabrics (166—169). In this case, polymeri2ation is used between an agent such as DMDHEU and a polyol to produce a hydrophilic network in the synthetic matrix (166—169). 

Before nitration the moisture content of the purified linters is reduced to well below 5% since the presence of water will modify the progress of the reaction and tends to produce undesirable products. The drying operation is carried out by breaking open the cotton linters and passing along a hot air drier. 

Carbohydrates occur in every living organism. The sugar and starch in food and the cellulose in wood, paper, arid cotton are nearly pure carbohydrates. Modified carbohydrates form part of the coating around living cells, other carbohydrates are part of the nucleic acids that carry our genetic information, and still others are used as medicines. 

Prepare 26 g. of molecular sodium in a 1500 ml. round-bottomed flask (Section II,50,d, Method 1). Cover the sodium with 625 ml. of sodium-dried A.R. benzene fit the flask with an efficient reflux condenser protected from the air by means of a calcium chloride (or cotton wool) guard tube. Add 151 5 g. of diethyl adipate (Sections 111,99 and 111,100) in one lot, followed by 1 6 ml. of absolute ethyl alcohol. Warm the flask on a water bath until, after a few minutes, a vigorous reaction sets in and a cake of the sodio compound commences to separate. Keep the flask well shaken by hand during the whole of the initial reaction. After the spontaneous reaction has subsided, reflux the mixture on a water bath overnight, and then cool in ice. Decompose the product with ice and dilute hydrochloric acid (1 1) add the acid until Congo red paper is turned blue. Separate the benzene layer, and extract the aqueous layer with 100 ml. of benzene. Wash the combined extracts with 100 ml. of 5 per cent, sodium carbonate solution and 160 ml. of water dry over a KWe anhydrous magnesium sulphate. Remove the benzene under atmospheric pressure (Fig. II, 13, 4, but with modified Claisen flask), and fractionate the residue under reduced pressure. Collect the 2-carbethoxy-epelopentanone at 108-111°/15 mm. (96 g.). Upon redistillation, the product boils at 102°/H mm. 

The recent introduction of genetically modified crops has changed both the agriculture and food industries. United States Department of Agriculture (USDA) surveys report that 25% of corn, 61% of cotton and 54% of soybean acreage grown in the USA in 2000 were genetically modified. ... 

Modified Plant Wood pulp and cotton Cellulose derivatives ... 

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