Adhesive

Description

Any non-metallic substance used to adhere one surface to another. Adhesives provide a wide selection of properties, solubility, tackiness, bonding time, and bonding strength. They can be used on nearly every kind of surface, such as wood, glass, metal, plastic, paper, fabric, and rubber. Adhesives are usually activated by water, solvents, pressure, heat, cold, or UV radiation. In some cases, surface treatment, abrasion, or an adhesion promoter may be needed to increase the strength or durability of the adhesive bond. Alternative binding techniques include sewing, mechanical fasteners and welding.

Adhesives may be classified as inorganic and organic adhesives:

• Inorganic adhesives: Water glass, Plaster of Paris and Portland cement.
• Organic adhesives: animal (hide, bone, blood, casein, etc.), or vegetable (Starch, Gum, Natural resin, etc.) or synthetic (Acrylic, Vinyl acetate, Cyanoacrylate, Epoxy, Silicone, etc.).

Please see tables below for more information.

Natural Adhesives

Adhesive	Examples	Earliest use	Composition	Properties	Applications
Albumin	Blood glue, egg glue	Ancient times	Protein-based made from blood or eggs	Dark color, water-soluble powder that dries to a water-resistant film when activated with an alkali	Plywood, masonry
Asphalt, Bitumen, Pitch, Tar	birch-bark tar, pitch, bitumen asphalt	Ancient times	Thick hydrocarbon-based liquids distilled from plants, wood or oil/coal deposits	Typically dark and viscous, softens with heat, may evolve volatile compounds; water-repellant	Boats, water-proofing
Casein	Milk glue	Ancient times	Protein-based made from milk curd mixed with alkalis	Water resistant; tensile strength eceeds most woods, non-toxic	Woodworking, paper glue, fireproofing; glass bottle labels, gilding leather
Gelatin	Hide glue, Rabbitskin glue, Bone glue, Fish glue, Isinglass	Ancient times	Hydrolyzed collagen made from animal connective tissue and bones; hides are acid-treated, neturalized and repeatedly soaked	Hardens when cooled; may be slightly brittle; water-soluble	Cabinetmaking, bookbinding, sizing fabrics
Keratin	Hoof, Horn	Medieval or earlier	Partially hydrolyzed keratin; hooves or horns are fragmented then boiled and acidified.	Hardens when cooled; does not become brittle	Gluing and stiffening textiles, cabinetmaking, glass sealant
Mucilage	Agar, Algin	Ancient times	Polar glycoprotesin and exopolysaccharid etracted from plants and seeds	Viscous; soluble in water; edible; low bonding strength; sensitive to moisture, biodegradation and insects	postage stamps, labels on metal cans
Starch	potato, rice, wheat; Paste	1847	Starch granules swell in water for form a thick tacky gel upon cooling	Soluble in cold water; become brittle with age; sensitive to moisture, biodegradation and insects	Postage stamps, corrugated board, wallpaper
Tree resins	Balsam, Dammar, Gum arabic, Mastic	Ancient times	Clear to translucent resins soluble in alcohol or turpentine; insoluble in water	Darken with age	Adhere jewels and beads, repair broken vessels
Wax	Insect wax (Beeswax), plant wax (carnauba); Mineral wax (Paraffin)	Ancient times	Long-chain hydrocarbons	Becomes soft with heat	Repair broken vessels; adhere pigments and inks
Rubber (natural, vulcanized)	Rubber cement; latex	1830 to WWII	Natural exudation obtained from plants, usually dissolved in solvent	Solvent evaporates as it sets; latex may be an allergen; waterproof, discolors and cracks with time	Used prior to synthetics

Synthetic Adhesives

Adhesive	Examples	Documented use	Composition	Properties	Applications
Acrylic (solvent-based)	UHU All Purpose clear adhesive; Bostik All Purpose clear adhesive; 3M Brand PSA backing adhesive	1940s	Solvent cured acrylic resin often containing fillers like calcium carbonate, silica, and plasticizer.	Clear, strong, fast setting glue that adhere to a wide range of materials
Acrylic latex	Flugger; Weld-On acrylic cement; Trinseo	1950s	Butyl methacrylate, calcium carbonate, water	inexpensive, fast-drying, and paintable; minimal shrinkage; used indoors	Popular white glue commonly used in houses and schools
Arylic (pressure-sensitive)	most 3M brand tapers		Methacrylate copolymers on polyethylene or polypropylene substrates; may contain tackifiers	Low cost, thermally and oxidatively stable, optically clear.	Used for plastic, paper, fabric, tapes and labels
Acrylonitrile polymers	Acrylonitrile -butadiene,; acrylonitrile-butadiene Styrene (ABS); Styrene-Acrylonitrile (SAN); Nitrile rubber; Permabond		Solvent borne adhesive composed of acrylonitrile -polymer combinations along with solvent, tackifier and plasticizer	Bonds vinyl, other elastomers and fabrics; provides good wear, oil and water resistance; may be used for under watr applications
Butyl rubber (synthetic)	Butyl mastic, Buna-N rubber	1950s	Isobutylene-isoprene, talc calcium carbonate, mineral spirits, adhesion promoters	Elastomeric with excellent peel strecngth but low shear strength; sticky and messy; more resistant to sunlight than natural rubbers; combustible; paintable	Primarily used outdoors for metal and masonry joints that may expand and contract (gutters)
Cyanoacrylate	Krazy glue, Superglue, Zap, ELFY, Eastman 910	1941	Thermosetting adhesive without heat or added catalyst	Difficult to remove; degraded by UV light and alkalis	Bonds metals to non-metals; used for glass, ceramic, and suturing skin
Epoxies	Ablebond, Araldite AY103; Hxtal Nyl-1, Phiilyseal, CM Nond, Epotek, UHU	1939	A famil y of thermosetting resins that polymerize with themseolves or with co-reactants. Th reaction is exothermix	High strength, good abrasion and chemical resistance, low water absorption; used for paint,coating, hard-plastics as well as adhesives; may cause allergic reactions	Bonds wood, metal, glass , stone and some plastics
Ethylene vinyl acetate	hot-melt glues, Elvax, A-C copolymer, Vinamul, Mowilith, Elvace 1874, Jade 834		polyethylene mixed with about 10-40% vinyl acetate	thermosetting polymer with rubber-like characteristics; soft, flexible material is waterproof, tough and stress-crack resistant; it has high cohesive strength and fast-setting speed	Bond textiles, paper, glass; used as carpet backing adhesive
Phenol formaldehyde	phenolic resin, resorcinol, Bakelite	1907		Temperature and UV resistant; off gases phenol and formaldehyde; water soluble until set; low cost; darkens in sunlight	Used for laminating plywood especially for outdoor use
Urea formaldehyde		1896	Water-soluble resin	Off-gases urea, ammonia and formaldehyde, thermosetting; degraded by hear, acids, alkalis	Used for laminating plywood; particleboard
Polysulfide	Neoprene, Thiokol	1950s	Any synthetic rubber vulcanized with sulfur (Neoprene, styrene-butadiene, polyisoprene). Some polusulfide elastomers are used with epoxies to provide flexibility	will melt acrylic, polycarbonate, ABS and PVC plastics; can be used on nylon, epoxy, polyoxymethylene; may release sulfur; may contain PCBs; poor tensile strength; abrade easily; replaced in 1980s by silicone and urethane sealants	still used for chemically resistant tapes and gaskets in aircraft because of their vibration durability
Silicone	Silastic, Clear Museum gel, Dowsil RTV	1960s	Silicone resin cured with moisture or peroxides; may contain fumed silica, calcium cabonate, ground quartz, carbon black, talc, plasticizers, acetone, methylene chloride. May be clear, white, or colored	water-repellent; long-life; wide temperature range; mold/mildew resistant; not paintable; poor adhesion; may release acetic acid or methanol on cure; may have residual curing compounds and silicone oils; may stain porous materials	Sealants are often used in outdoors settings; Pressure sensitive adhesives are used on skin for medical devices and drug delivery
Polyurethane	Gorilla glue	1937	Available and one- or two-component adhesives, solvent -free; may be bulked with limestone and/or quartz	shrink free; very durable; abrasion resistant; flexible at low temperatures; combustible producing toxic fumes; may release acetic acid on curing, aging, or deterioration; susceptiple to hydrolysis that may decrease adhesion	Strong adhesive for metal and glue; laying carpets and wood floor board; may dissolve some plastics
Vinyl latex	Vinyl emulsion; vinyl acrylic emulsion; white latex	late 1960s	Polyvinyl acetate as an emulsion in water usually with calcium carbonate, plasticizers and dispersing agents. Vinyl acrylic latex contains a co-polymer of vinyl acetate and butyl acrylate.	inexpensive; high stability; water-resistant when dry; may be used as a liquid or solid (for heat sealing); may evolve trace acetic acid as it cures;	Used for paper, textile, packaging, mounting photographs, laying carpets and floor tiles; also used as sealants and paints

Synonyms and Related Terms

kleefstof (Ned.); adhésif (Fr.); colle (Fr.); Klebstoff (Deut.); adesivo (It.); adhesivo (Esp.); adesivo (Port.); adhesiv (Sven.); bindemedel (Sven.); mastic; cement; glue; mucilage; paste;

Physical and Chemical Properties

General Characteristics of Polymers

Physical Properties for Selected Thermoplastic Resins

Physical Properties for Selected Thermoset Resins

Resources and Citations

• AIC Conservation Wiki: Adhesives for Use Inside Exhibit Cases
• Irving Skeist, Handbook of Adhesives, Van Nostrand Reinhold Company, New York, 1977
• Matte Paint: Its history and technology, analysis, properties and conservation treatment, Eric Hansen, Sue Walston, Mitchell Bishop (ed.), J. Paul Getty Trust, Los Angeles, Vol. 30 of AATA, 1993
• Matt Roberts, Don Etherington, Bookbinding and the Conservation of Books: a Dictionary of Descriptive Terminology, U.S. Government Printing Office, Washington DC, 1982
• Theodore J. Reinhart, 'Glossary of Terms', Engineered Plastics, ASM International, 1988
• Wikipedia: Adhesive (Accessed Feb. 2, 2006 and Feb 2023)
• G.S.Brady, Materials Handbook, McGraw-Hill Book Co., New York, 1971 Comment: p. 14
• Richard S. Lewis, Hawley's Condensed Chemical Dictionary, Van Nostrand Reinhold, New York, 10th ed., 1993
• The American Heritage Dictionary or Encarta, via Microsoft Bookshelf 98, Microsoft Corp., 1998
• Multilingual Glossary for Art Librarians at http://www.ifla.org/VII/s30/pub/mgl.htm
• Art and Architecture Thesaurus Online, http://www.getty.edu/research/tools/vocabulary/aat/, J. Paul Getty Trust, Los Angeles, 2000