Cellulose triacetate plastic

NFPA Health 2, Flammability 1, Reactivity 0 Uses Flame retardant plasticizer for cellulosics, coatings, triacetate film and sheet, engineering thermoplastics (PPO, HIPS, ABS-PC) noncombustible substitute for camphor in celluloid EP agent in lubricants in lacquers varnishes impregnating roofing paper infood-pkg. adhe-... 

Cellulose Triacetate n A member of the cellulosic plastics family made by reacting purified cellulose with acetic anhydride in the presence of a catalyst in such a manner that at least 92% of the hydroxyl groups are replaced by acetyl groups. Because of its high softening point this material cannot be molded or extruded. Its major use is for casting films or spinning fibers from solutions, such as in a mixture of methylene chloride and methanol. 

Polymer Plasticizer. Nylon, cellulose, and cellulose esters can be plasticized using sulfolane to improve flexibiUty and to increase elongation of the polymer (130,131). More importantly, sulfolane is a preferred plasticizer for the synthesis of cellulose hoUow fibers, which are used as permeabiUty membranes in reverse osmosis (qv) cells (131—133) (see Hollow-FIBERMEMBRANEs). In the preparation of the hoUow fibers, a molten mixture of sulfolane and cellulose triacetate is extmded through a die to form the hoUow fiber. The sulfolane is subsequently extracted from the fiber with water to give a permeable, plasticizer-free, hoUow fiber. 

Cellulose acetate [9004-35-7] is the most important organic ester because of its broad appHcation in fibers and plastics it is prepared in multi-ton quantities with degrees of substitution (DS) ranging from that of hydrolyzed, water-soluble monoacetates to those of fully substituted triacetate (Table 1). Soluble cellulose acetate was first prepared in 1865 by heating cotton and acetic anhydride at 180°C (1). Using sulfuric acid as a catalyst permitted preparation at lower temperatures (2), and later, partial hydrolysis of the triacetate gave an acetone-soluble cellulose acetate (3). The solubiUty of partially hydrolyzed (secondary) cellulose acetate in less expensive and less toxic solvents such as acetone aided substantially in its subsequent commercial development. 

The cellulose esters with the largest commercial consumption are cellulose acetate, including cellulose triacetate, cellulose acetate butyrate, and cellulose acetate propionate. Cellulose acetate is used in textile fibers, plastics, film, sheeting, and lacquers. The cellulose acetate used for photographic film base is almost exclusively triacetate some triacetate is also used for textile fibers because of its crystalline and heat-setting characteristics. The critical properties of cellulose acetate as related to appHcation are given in Table 10. 

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. 

Cellulose acetate and triacetate may be used as plastics or spun into fibers for textiles. They are made by the reaction of cellulose with acetic anhydride. 

Fig. 12. Complex piezoelectric strain constant of uniaxially drawn cellulose triacetate film plotted against temperature. Draw-ratio = 2. Plasticizer content = 10%. Frequency = 20 Hz. Drawn after Fukada, Date, and Emura [J. Soc. Mat Sci. Japan 17,335 (1968)] by permission of the Society of Materials Science, Japan...

Tetraethylene glycol may be used direcdy as a plasticizer or modified by esterification with fatty acids to produce plasticizers (qv). Tetraethylene glycol is used direcdy to plasticize separation membranes, such as silicone mbber, poly(vinyl acetate), and cellulose triacetate. Ceramic materials utilize tetraethylene glycol as plasticizing agents in resistant refractory plastics and molded ceramics. It is also employed to improve the physical properties of cyanoacrylate and polyacrylonitrile adhesives, and is chemically modified to form polyisocyanate, polymethacrylate, and to contain silicone compounds used for adhesives. 

It has already been implied that cellulose triacetate will not produce a thermoplastic, as its softening point cannot be reduced appreciably by plasticizers. It is used in solution processes, however, to produce films and libers. Triacetate films absorb less water than films of secondary cellulose acetate, and they arc therefore more dimensionally stable in environments where the humidity is not controlled. Triacetate fibers, with a similar resistance to water, impart to fabrics wrinkle resistance, dimensional stability, and the ability to dry rapidly. Under United Slates federal regulations, a filler must tic made from a cellulose acetate having... 

Like the triacetate, secondary cellulose acetate (CA) is used in solution processes to produce fibers and films. CA fibers were originally called "rayon." the name that was already in use for regenerated cellulose fibers. In 1951. however, the regulatory authorities formally acknowledged the chemical distinction between CA and cellulose, and the term rayon was reserved for libers of regenerated cellulose. CA fibers are officially called acetate. and they are used in a wide variety of fabrics. They also are used for cigarette filters. However, the majority of CA produced is used for manufacture of plastics. 

Cellulose Acetate and Triacetate Polymer. The production of acetate and triacetate polymer is accomplished by the esterification of high purity chemical cellulose, except for special plastic-grade acetates requiring low color and high clarity, where cotton linters are used... 

TRIACETATE See Cellulose Ester Plastics (Organic) Fibers. 

K.M. White, B.D. Smith, P.J. Duggan, S.L. Sheahan and E.M. Tyndall, Mechanism of Facilitated Saccharide Transport through Plasticized Cellulose Triacetate Membranes, J. Membr. Sci. 194, 165 (2001). 

Paugam, M.F. and Buffle, J. (1998) Comparison of carrier-facilitated copper (II) ion transport mechanisms in a supported liquid membrane and in a plasticized cellulose triacetate membrane. Journal of Membrane Science, 147, 207. 

The Dylux 503 formulation contained a HABI, the leucodye TLA-454, a mixture of quinones, triethanolamine triacetate, several plasticizers, an organic acid, cellulose acetate butyrate binders, as well as antiblocking agents (fluorinated derivatives) as well as a silica derivative to provide tooth to the coating. The selection was made to provide maximum performance at minimum mill cost. The paper substrate required had high holdout, so as to permit two-sided coatings as well as to minimize the wicking of chemistry into the base. 

Cellulose acetate, Plasticized cellulose triacetate, Cellulose acetate methyl carbamate, Cellulose acetate Ethyl- carbamate, Cellulose acetate phthalate, Cellulose acetate succinate... 

Smith BD. Facilitated transport of sugars and amino acids through plasticized cellulose triacetate membranes. Polym Mater Sci Eng 1997 77 269-270. 

Gherroue, A., Kerdjoudj, H., Molinari, R., Seta, P., and Drioh, E., Eixed sites plasticized cellulose triacetate membranes containing crown ethers for silver(I), copper(ll) and gold(III) ions transport. J. Membr. Sci., 2004, 228 149-157. 

Amylose triacetate prepared from butanol-precipitated starch may be plasticized with almost any of the common plasticizers which are applicable to the plasticization of cellulose triacetate. For example, some suitable plasticizers are dimethyl or diethyl tartrate, tributyl citrate, tributyl phosphate, tricresyl phosphate, polyethylene glycol, and pentaerythritol tetraacetate. Addition of only 10-20% plasticizer is sufficient to give amylose triacetate films a useful and lasting degree of... 

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