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... The reactive groups in silk are intimately related to the absorp tion of moisture, acids, alkalies, or dyes, and to physical properties such as extensibility and tensile strength. A large proportion of these gorups are present in silk fibroin in the form of hydroxyl groups of the amino acid tyrosine. The latter groups are of special interest, partly because of their preponderance, but principally ...
... The reaction of cotton cellulose with β-propiolactone may be effected in the presence of strong alkalies such as sodium hydroxide and potassium hydroxide. Monoethanol amine and trimethylbenzyl ammonium hydroxide will also catalyze the reaction, but to a lesser degree. Di- and triethanolamine are ineffective. Byproducts of the reaction are water soluble and may be removed with a hot-water wash. Con ...
... The application of some fluorocarbon compounds to cotton textiles to impart oleo phobic and hydrophohic surface characteristics to the materials has been investigated Commercial and laboratory preparations of poly (fluoroalkyl esters of acrylic acid) and of chromium complexes of fluorine-containing monocarboxylic acids were used to treat cotton fabrics, thereby substituting low energy -CF₃ and -CF ...
... Many cellulose derivatives are known to be water- or alkali-soluble, The solubility of these derivatives which are principally esters and ethers has been found to be a func tion of the degree of polymerization, the nature of the substituent group, decree of substi tution, method of preparation, and type of solvent. A few soluble fibers have been pre pared from cotton in which the fibrous form of t ...
... Partial esters of cellulose varying in degree of substitution from 0.02 to 0.58 were prepared by reacting cellulose immersed in dimethylformamide with either perfluoro butyryl chloride or perfluorooctanoyl chloride in the presence of a tertiary aromatic amine. The use of essentially homogeneous solutions of acid chlorides resulted in prod ucts which retained properties of the original cotton and s ...
... A survey was given on the results of starch research, which have been achieved during the past ten years. By means of an electronic microscope, new knowledge was gained on the formation and the construction of cereal starch grains. Economic methods for the separation of amylose and amylopectin were developed. In addition, extensive experiments for the cultivation of corn with high amylose content ...
... Progress in developing cotton fabrics having high recoverable stretch, durable loft, warmth, and other highly desirable properties is reported. Three general methods for making stretch and bulked cotton yarns and fabrics are described: (i) use of cross- linking agents to set or maintain crimp in cotton yarn; (ii) slack mercerization of cotton fabrics to cause shrinkage; and (iii) the crimping and ...
... With a view to studying the effect of bulky substituents in the cross-linking molecule on the physico-chemical properties of reacted cellulose, 1:3-dichloro-2-propanol and its acetyl, propionyl, and butyryl esters have been reacted with cellulose. Two cotton fabrics have been used: (i) a casement cloth of open structure and (ii) a poplin fabric of closed construction. The presence of cross-links a ...
... Three commonly used solubility tests have been applied to wools treated with various mono- and bifunctional active esters. Treatment with the bifunctional esters invariably leads to large reductions in solubility. Those monofunctional esters which introduce bulky groups into wool also decrease its solubility. However, bifunctional reagents reduce the solubility to a greater extent than monofunctio ...
... The effects on cotton of esterification to low degrees of substitution have been investi gated by light and electron microscopy. Observations were made on partially esterified celluloses which included esters of acetic, palmitic, stearic, 12-hydroxystearic, linoleic, and ricinoleic acids and of the aromatic benzoic, cinnamic, naphthoic, and pkenylundecanoic acids. The uniformity of the esterificat ...