Animal glues and technical gelatins

Production of animal glue is considered as environmentally friendly , since it involves conversion of unpleasant waste into useful products, but economic operation depends on satisfactory disposal of residues some of these are used as slow-release nitrogenous fertilizers. The mineral residue from bone glue production ( bone meal ) by thermal methods is used as a phosphate supplement in animal feed and fertilizers it is also calcined at 1000-1200 °C to produce calcined bone, used in the manufacture of bone china to provide strength and translucency. Animal glues and technical gelatins contain added preservatives and a proportion of non-protein materials, usually mucopolysaccharides and soluble inorganic salts. These impurities differ with the source of raw material. 

Water-based dispersions or emulsions such as polyvinyl acetate, acrylics, polyvinyl chloride and polyvinyl alcohol with plasticizers and tackifiers. In addition, this range can include urea formaldehyde and phenolic adhesives, resins, natural adhesives produced from starch, dextrin, casein, animal glues (see Polyvinyl alcohol in adhesives, Phenolic adhesives single-stage resoles. Phenolic adhesives two-stage novolacs. Animal glues and technical gelatins) and rubber latex (see Emulsion and dispersion adhesives). Solvent-free 100% solids such as polyurethane. Hot melt adhesives include Ethylene-vinyl acetate copolymers, polyolefins, polyamides, polyesters with tackifiers and waxes. More recent additions include cross-linkable systems. 

Animal glues and technical gelatins C A FINCH Origin and uses... 

Syn. Animal Glue Technical ->Gelatin G. Tierischer Leim E colie forte G. derives from the protein - collagen, extracted from hides and bones of animals. Animal glue and gelatin have the same structure (- gelatin). G. can be made from bone or skin wastes. Waste fish proteins are sometimes also used. 

Selected animal glues, also known as technical gelatins, are used in the production of protein hydrolysates for use as a source of protein in such products as cosmetics, shampoos, and skin care lotions and creams. Generally, the glue protein is hydrolyzed to a molecular weight below 2000 by use of enzyme, acid, or alkaline treatment. 

Technical gelatin and animal glue, on the other hand, have seen their market share considerably eroded in the last 25 years. This decline has been brought about by the advent of synthetic polymers, which have taken over the sizing of synthetic fibers and the binding of paperback books. (But telephone books and catalogs have stayed with animal glue because of its superior durability and flexibility as well as lower cost.)... 

It is estimated that domestic consumption of technical gelatin and animal glue is 25-30 million pounds per year. ... 

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