In cellulose

The configuration of the glucoside linkage is different in the two, however. Structures [I] and [II], respectively, illustrate that the linkage is a /3-acetal-hydrolyzable to an equitorial hydroxide—in cellulose, and an a-acetal-hydrolyz-able to an axial hydroxide—in amylose, a starch ... 

The cellulose molecule contains three hydroxyl groups which can react and leave the chain backbone intact. These alcohol groups can be esterified with acetic anhydride to form cellulose acetate. This polymer is spun into the fiber acetate rayon. Similarly, the alcohol groups in cellulose react with CS2 in the presence of strong base to produce cellulose xanthates. When extruded into fibers, this material is called viscose rayon, and when extruded into sheets, cellophane. In both the acetate and xanthate formation, some chain degradation also occurs, so the resulting polymer chains are shorter than those in the starting cellulose. 

Acetic anhydtide is a mature commodity chemical ia the United States and its growth rate in the 1970s and 1980s was negative until 1988 when foreign demand neatly doubled the exports of 1986. This increase in exports was almost certainly attributable to the decline in the value of the U.S. doUar. Over four-fifths of all anhydtide production is utilized in cellulose acetate [9004-35-7] manufacture (see Cellulose esters). Many anhydtide plants are integrated with cellulose acetate production and thus employ the acetic acid pyrolysis route. About 1.25 kg acetic acid is pyrolyzed to produce 1.0 kg anhydtide. 

Antimony Oxide as a Primary Flame Retardant. Antimony oxide behaves as a condensed-phase flame retardant in cellulosic materials (2). It can be appHed by impregnating a fabric with a soluble antimony salt followed by a second treatment that precipitates antimony oxide in the fibers. When the treated fabric is exposed to a flame, the oxide reacts with the hydroxyl groups of the cellulose (qv) causing them to decompose endothermically. The decomposition products, water and char, cool the flame reactions while slowing the production and volatilization of flammable decomposition products (see Flaa retardants for textiles). 

Triphenyl phosphate [115-86-6] C gH O P, is a colorless soHd, mp 48—49°C, usually produced in the form of flakes or shipped in heated vessels as a hquid. An early appHcation was as a flame retardant for cellulose acetate safety film. It is also used in cellulose nitrate, various coatings, triacetate film and sheet, and rigid urethane foam. It has been used as a flame-retardant additive for engineering thermoplastics such as polyphenylene oxide—high impact polystyrene and ABS—polycarbonate blends. 

MiscelUneous. Mahc acid is used in pharmaceuticals (qv), cosmetics (qv), dentifrices (qv), metal cleaning, electroless plating (46), wash-and-wear textile finishing (47—49), for stabilization of heat-sensitive copying paper (50), as an inhibitor of gelation, livering, and agglomeration in cellulose nitrate Hqueurs, and in many other appHcations. 

DMEU represented the first cross-linking agent that was a pure chemical rather than a mixture of components. As such, it provided research workers a tool to investigate the changes that take place in cellulose with cross-linking in a more exact manner (70—73). 

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