Hydroxides, inorganic

The nitro alcohols available in commercial quantities are manufactured by the condensation of nitroparaffins with formaldehyde [50-00-0]. These condensations are equiUbrium reactions, and potential exists for the formation of polymeric materials. Therefore, reaction conditions, eg, reaction time, temperature, mole ratio of the reactants, catalyst level, and catalyst removal, must be carefully controlled in order to obtain the desired nitro alcohol in good yield (6). Paraformaldehyde can be used in place of aqueous formaldehyde. A wide variety of basic catalysts, including amines, quaternary ammonium hydroxides, and inorganic hydroxides and carbonates, can be used. After completion of the reaction, the reaction mixture must be made acidic, either by addition of mineral acid or by removal of base by an ion-exchange resin in order to prevent reversal of the reaction during the isolation of the nitro alcohol (see Ion exchange). 

The carbon black generated by a fire from a rubber source increases the smoke density other products are highly toxic and often corrosive. The halogens, phosphates, borates, and their acids evolved during a fire corrode metals and electrical and electronic equipment. Hence many of the fire retardants described below cannot be used in situations where the toxic gases evolved will create their own hazards. In these cases inorganic hydroxides are used, at filler-type addition levels. Aluminium hydroxide and magnesium hydroxide are used as non-toxic fire retardant systems. 

Acetic acid also reacts with inorganic hydroxides (e.g., sodium hydroxide) forming water soluble acetates. The reaction is very exothermic. 

Suspended particles may consist of complex inorganic hydroxides and silicates or, sometimes, organic debris. Particles too small to be easily distinguished can cause difficulties when a drink is carbonated, acting as minute centres of instability resulting in a loss of carbonation, foaming (gushing) at the filler-head and variable fill volumes. 

The slip coating-sintering procedure can be used to make membranes with pore diameters down to about 100-200 A. More finely porous membranes are made by sol-gel techniques. In the sol-gel process slip coating is taken to the colloidal level. Generally the substrate to be coated with the sol-gel is a microporous ceramic tube formed by the slip coating-sintering technique. The solution coated onto this support is a colloidal or polymeric gel of an inorganic hydroxide. These solutions are prepared by controlled hydrolysis of metal salts or metal alkoxides to hydroxides. 

The addition of very small amounts of fine carbon fibers73 or polyacrylonitrile fibers74 can reduce the level of inorganic hydroxide required to achieve UL94 V-0 flammability ratings in polyolefin compounds. These secondary additives are thought to function as char promoters. 

Horn, W.E., Inorganic hydroxides and hydroxy carbonates Their function and use as flame-retardant additives, in Fire Retardancy of Polymeric Materials, Grand, A.F. and Wilkie, C.A. (Eds.), Marcel Dekker, Basel, Switzerland, 2000, Chapter 9. 

ALUM (10043-01-3) Al2(SOj3 Noncombustible solid. Forms sulfuric acid with water. Aqueous solution has a violent reaction with bases, amines, amides, inorganic hydroxides, and many other materials. See also sulfuric acid. Dry material is weakly corrosive to carbon steel aqueous solution attacks aluminum and other metals, forming hydrogen gas. Hydrogen gas can accumulate to explosive concentrations within enclosed or confined spaces. 

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