Cotton cellulose-polyvinyl

Table VI. Properties of Cotton Cellulose—Polyvinyl Copolymera Yarns...

Table VIII. Rot Resistance of Cotton Cellulose-Polyvinyl Copolymer Yarns...

Table IX. Weather Resistance of Cotton Cellulose—Polyvinyl Copolymer Yarns...

Graft and block copolymers of cotton cellulose, in fiber, yam, and fabric forms, were prepared by free-radical initiated copolymerization reactions of vinyl monomers with cellulose. The properties of the fibrous cellulose-polyvinyl copolymers were evaluated by solubility, ESR, and infrared spectroscopy, light, electron, and scanning electron microscopy, fractional separation, thermal analysis, and physical properties, including textile properties. Generally, the textile properties of the fibrous copolymers were improved as compared with the properties of cotton products. 

The modification of the properties of fibrous cotton cellulose through free-radical initiated copolymerization reactions with vinyl monomers has been investigated at the Southern Laboratory for a number of years. Both graft and block copolymers are formed. Under some experimental conditions the molecular weight of the polyvinyl polymer, covalently... 

This includes wire enamels on a base of polyvinyl formal, polyurethane or epoxy resins as well as moulding powder plastics on phenol-formaldehyde and similar binders, with cellulose fillers, laminated plastics on paper and cotton cloth base, triacetate cellulose films, films and fibres of polyethylene terephthalate. 

Figure 4-10. Schemetic diagram of events causing detergency [7], oriented soap molecules assumes a net negative charge similar to the globular micelle of soap. Cotton fibres also take up a negative charge when immersed in water. The electrostatic repulsions between the particles and the fibre play a major role in preventing redeposition. The addition of carboxymethyl cellulose (CMC) and/or polyvinyl pyrolidone (PVP) (Fig. 4-11) can act as anti-redeposition agents.

Synthetic fiber (man-made fiber) n. A class name for various fibers (including filaments), distinguished from natural fibers such as wool and cotton, produced from fiber-forming substances which may be (1) Modified or transformed natural polymer, e.g., alginic and cellulose-based fibers such as acetates and rayon s. (2) Polymers synthesized from chemical compounds, e.g., acrylic, nylon, polyester, polyurethane, polyethylene, polyvinyl, and carbon/graphite fibers. (3) Fibers of mineral origin, e.g., glass, quartz, boron, and alumina. 

Bleached cotton linters with a degree of polymerization (DP) of 1,300 were used as the starting cellulose sample. The cellulose was first dried imder vacumn at 40°C. A, A -dimethylacetamide (DMAc) purchased from Katayama Chemicals Co. Ltd. (99+%) was dehydrated with molecular sieve 3A and used without further purification. Lithium chloride (LiCl) powder (Katayama Chemicals Co. Ltd.) was oven-dried at least for 3 days at 105°C. Methylcellulose with a degree of substitution (DS) of 1.6 and polyvinyl alcohol (PVA) with a DP of 2,000 were purchased from Shin-Etsu Chemical Co. Ltd. and Katayama Chemicals Co. Ltd., respectively. Cellulose acetate with a DS of 2.45 (L-70) and purified chitin were provided by Daicel Chemicals Co. Ltd. and Katakura Chikkarin, respectively. 

A modified polymer, also called a semisynthetic polymer, is a natural polymer compound treated by a chemical reaction. The world s first man-made polymer material—cellulose nitrate—was made from natural cellulose, such as cotton or cotton cloth, that was treated with concentrated nitric acid and concentrated sulfuric acid. A synthetic polymer is a polymer compound synthesized by small molecular weight compounds through chemical methods. Examples of synthetic polymer materials are plastics such as polyethylene, polypropylene, and polyvinyl chloride and fibers such as polyester, nylon, and other synthetic fibers. 

International Fiber Science and Technology Series, Marcel Dekker, New York (a) Volume 7, M. Lewin, E. M. Pearce (eds.). Fiber Chemistry, 1985 (polyester, polyamide, acrylic, polypropylene, polyvinyl alcohol, wool, silk, cotton, rayon, cellulose acetate) ... 

Garside and Wyeth [60] have used Fourier transform infrared spectroscopy to characterise cellulose fibres such as jute, sisal, and cotton. The technique has also been used to determine low levels of polyvinyl pyrrolidinone in polysulfone [61]. Weiss and co-workers [62] used Fourier transform infrared microspectroscopy in the study of organic and inorganic phases of an injectable hydroxypropylmethylcellulose-calcium phosphate composite for bone and dental surgery. 

Sometimes several purposes can be served at once. Chlorination of natural rubber decreases the flammability of the polymer. At the same time, it raises the 7 so that the polymer can be used as a binder for traffic paints. Nitration of cellulose allows the native cotton to be plasticized and molded. Flammability is enhanced at the same time. This may be a disadvantage to makers of molded articles for decoration and apparel. However, the munitions manufacturer regards the flammability and propellant power of guncotton, cellulose nitrate, as its most important advantage. Most often a polymer modification is economically justifiable only when the original polymer occurs naturally or as a by-product. Sometimes modification is the only good way to make a material. A case in point is the photosensitive polymer polyvinyl cinnamate. 

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