Glutin adhesive

Glutin adhesives are used in form of jellies which are processed at 50-70 °C. Due to a sol-gel transition, very fast setting is achieved and a high production speed is reached. However, the adhesion spectrum of glutin glues is normally not very wide. 

Old nat. adhesives old (historic) natural adhesives, e.g. starch, glutin, casein adhesives. 

Adhesives from Diisocyanates and Proteins. Protein-based adhesives have been used as traditional binders for wood since the beginning of wood products manufacture. Glutin and casein binders can provide interior-grade wood products but with modified casein binders, even panels for exterior use are possible. For economic and technical reasons, protein-based wood adhesives have been replaced more and more by synthetic adhesives since the beginning of the century. 

UF, urea-formaldehyde resin MUF, melamine fortified UF resin MF/MUF, melamine and melamine-urea resins (MF resins are only used mixed/coreacted with UF resins MUPF, melamine-urea-phenol-formaldehyde resin PF/PUF, phenol and phenol-urea-formaldehyde resin (P)RF, resoreinol-(phenol-)formaldehyde resin PMDI, polymeric methylenediisocyanate PVAc, polyvinylacetate adhesive old nat.adhesives, old (historic) natural adhesives (e.g., starch, glutin, casein adhesives) nat.adhesives, natural adhesives (e.g., tannins, lignins, carbohydrates) inorg.adhesives, inorganic adhesives (e.g., cement, gypsum) activation activation constituents of wood to function as adhesives (i.e., lignin). 

Solutions of natural and synthetic high molecular mass substances in water, e.g., starch, dextrins, casein, cellulose ethers, water-soluble derivatives of poly(acrylic acid), poly(vinyl alcohol), poly(vinyl pyrrolidone) (adhesive sticks). Uses paper, fiberboard. Glutins (glues of animal origin). Uses wood, paper, fiberboard, moistenable adhesive tapes. 

Hot-melt adhesives are 100% solids that, in the broadest sense, include all thermoplastic polymers. Polymers that are primarily used as hot-melt adhesives include ethylene-vinyl acetate copolymers (EVA), polyvinyl acetates (PVA), polyethylene (PE), amorphous polypropylene, block copolymers (thermoplastic elastomers), polyamides, and polyesters. The oldest hot-melt adhesive, which has been in use since early times, is sealing wax. In principle, glutins and glue jellies also may be regarded as hot-melt adhesives. However, modern hot-melt adhesives are primarily synthetic products. The simplest hot-melt adhesives are rosin-wax mixtures. But these products have limited strength and thermal stability. 

Lamination of Paper and Board. Adhesives based on starch, dextrin, glutin and poly(vinyl alcohol), and also emulsion adhesives, mainly polyfvinyl acetate), are used for the lamination of paper and board. Only when high initial tack and a lay-flat effect are required are hot glues based on glutin still in use. Starch-based adhesives modified with silicate, casein-stabilized copolymer dispersions, and rubber latices are used in the lamination of paper to aluminum foils. Modified polyacrylate solutions and reactive polyurethane adhesives are used mainly for paper-to-plastic lamination. 

Tube Winding. Mainly dextrin adhesives are used and/or plasticized homopoly-meric poly(vinyl acetate) emulsions, but glutin glues are also used in special cases. 

Today for the assembly gluing of wood, for gluing veneers, plastic sheets, and films, and for the manufacture of wood-based materials (chipboard, plywood, hardboard, profiles), synthetic adhesives are used almost exclusively. The traditional use of adhesives based on natural products (glutin and casein glues) is confined to a few special cases only (for example, violin making). 

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