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Naturally Occurring Polymers—Plants
Published in Charles E. Carraher, Carraher's Polymer Chemistry, 2017
While other organic esters are commercially available, namely, cellulose butyrate and cellulose propionate, by far the most widely used one is cellulose acetate. Cellulose acetate is available as plastics, in films, sheets, fibers, and lacquers. Cellulose acetate is used in the manufacture of display packaging and as extruded film for decorative signs, and to coat a variety of fibers. Injection-molded products include toothbrush handles, combs, and brushes. It is also used in lacquers and protective coatings for metal, glass, and paper. Cellulose acetate films are used in reverse osmosis to purify blood, fruit juices, and brackish water. Some eyeglass frames are made of cellulose acetate. Biodegradable film, sponges, and microencapsulation of drugs for controlled release also utilize cellulose acetate. Cellulose triacetate is used for photographic film bases. Numerous continuous filament yarns, tows, staples, and fibers are made from cellulose acetate. The precise form of filament produced is controlled by a number of factors, including the shape of the die. Table 9.6 presents representative physical properties for cellulose acetate.
Fibers and Filaments
Published in Tom Cassidy, Parikshit Goswami, Textile and Clothing Design Technology, 2017
Tom O’Haire, Parikshit Goswami
Cellulose can also be modified by acetylation to produce cellulose acetate and cellulose triacetate. In these products, the hydroxyl (–OH) groups are replaced partially or fully by acetyl groups to aid dissolution in solvents such as chloroform or dichloromethane. The fiber is then dry–wet spun in ambient air, needing no precipitant. The acetylation of the –OH groups severely inhibits the formation of hydrogen bonds in cellulose acetate as the new chemical groups do not form such bonds with water. This means that cellulose acetate and triacetate holds crease and pleat very well, often being found in pleated skirts and in blends with silk, nylon, and PET.
Industrial Polymers
Published in Manas Chanda, Plastics Technology Handbook, 2017
Sheeting and films of cellulose triacetate are used in the production of visual aids, graphic arts, greeting cards, photographic albums, and protective folders. Cellulose triacetate is extensively used for photographic, x-ray, and cinematographic films. In these applications cellulose triacetate has displaced celluloid mainly because the triacetate does not have the great inflammability of celluloid.
Irradiation induced modification of optical properties of PANI-Cu/PMMA and PANI-Cu/CTA nanocomposites
Published in Radiation Effects and Defects in Solids, 2021
S. A. Nouh, M. ME. Barakat, Renu Gupta, K. Benthami, Radiyah A. Bahareth
Polymers are categorized according to the sort of bonding into either saturated or conjugated scheme. This classification is based on the presence of alternating C = C and C–C bonds (i.e. conjugate) along the polymer backbone or not. Cellulose triacetate (CTA) as a saturated polymer has significant appliances (17) in photography, holography, polarization and dosimetry. The optical properties such as birefringence and absorption coefficient are of special interest (18). CTA [C6H7O2(OOCCH3)3]n is made from cellulose by heterogeneous acetylation of the corresponding respective cello-oligosaccharide and purified by recrystallization twice from ethylacetate–hexane. All the six OH groups in the cellobiose units of cellulose are substituted by six COOCH3 groups. It is usually an amorphous polymer and rigid as supposed from the molecular structure (17). It is an excellent host material for PANI NCPs and has the advantages of transparent film formation. Numerous researches focusing on the physical properties of PANI/CTA blends have been reported (19,20).