There are many adhesive substances that are considered or commonly referred to as glue. Historically, the term only referred to protein colloids prepared from animal flesh. The meaning has been extended to refer to any fluid adhesive.
Plant- and animal-based adhesives
Solvent-type glues
Solvent adhesives temporarily dissolve the substance they are gluing, and bond by solvent-welding material together with the re-solidified material.
Synthetic glues
Synthetic monomer glues
Synthetic polymer glues
Thermoplastic polymers
Thermoplastic glues including hot-melt adhesives cure reversibly as they cool, like the gelatin and keratin glues listed above. They frequently don't emit volatiles unless overheated.
Styrene acrylic copolymer – e.g. "No More Nails"
Thermosetting polymers
Thermosetting glues or thermosets cure irreversibly by polymerization. The polymerization can be triggered by heat or other radiation, or high pressure or a catalyst/hardener may be added.
Epoxy resins Epoxy putty Polyvinyls Polyvinyl acetate (PVA) Includes white glue (e.g. Elmer's Glue) and yellow carpenter's glue (Aliphatic resin) (Brands include Titebond and Lepage) Polyvinyl alcohol Polyvinyl chloride (PVC) Polyvinyl chloride emulsion (PVCE) – a water-miscible emulsion that polymerizes as it cures Polyvinylpyrrolidone (component of glue sticks) Silicone resins Silyl modified polymers
By use Postage stamp gum may be a mixture of assorted starch and resin adhesives Library paste is usually starch-based Meat glue is a variety of culinary binding agents
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