Glues and Gum Adhesives

Glues and gums are industrial adhesives. Animal glues include hide glues, casein or milk protein glues, and fish-based glues. Hide glues are produced by hydrolysis or by boiling collagen, protein or gelatin from animal bones, hide, hooves or horns. Collagen, hide glue and gelatin are very closely related in terms of protein and chemical composition. Casein-based adhesives (carpenter's glues) are derived from milk.  Vegetable glues are made from plant-based proteins or modified starches. Soy protein glues are finding increased application. 

Gum adhesives or mucilage are based on polysaccharides derived from various plant exudates such as an oleoresin or gum resin. Gum adhesives are gelatinous when moist and harden on drying. Gum adhesives are the salts of complex organic acids. Mucilage contains proteins and polysaccharides and is similar to vegetable plant gums adhesives. Mucilage is a gelatinous substance extracted from legumes and seaweeds.