History of Bonding : A Timeline
3 billion years ago
Bonding-type processes in primordial cells: They produce a tacky outer membrane which allows them to stick to adjacent cells and form clumps and colonies. Mussels form high-strength bonds to a wide variety of surfaces; Sundew and spiders produce tacky secretions; Bees produce plates of wax; Birds make the first “bonded” composite materials for nest building.
80,000 years ago
From this time onwards, people used bonding: Cavemen near the Dead Sea made collages. In excavations bonding materials have been identified as decoration on skulls, as sealant for containers and as an adhesive.
3500 years ago
Animal blood and protein used as a binder for the base surface for cave paintings; Hut structures made of wood, brushwood and reeds that are strengthened with adhesive.
8000 B.C.
Weapons in advanced hunting cultures: Resins from trees provide enhanced bonding for joining flint and bone heads with wooden handles/shafts; “Adhesive pastes” produced by boiling down plant components; “Glues” produced by boiling down animal components.
5000 B.C.
In Mesopotamia and Egypt: Use of asphalt (naturally occurring) as an adhesive (mosaics), and in combi¬nation with resins used as a sealant for boats.
2000 B.C.
Near East: Gelatin glue for furniture manufacture.
1000 B.C.
China: Skin adhesives for lacquering work: Sap from the lacquer tree evaporates and can bond up to 30 different layers.
1500 A.D.
The Spaniards brought rubber to Europe from Central America where it had already long been used by Aztecs and Mayans; Casein, which was even known to the Romans, was the first “plastic” to be used for coating paper and bookbinding.
1700
Large-scale glue boiling.
1841
Rubber vulcanization was discovered (Goodyear).
1905
Baekeland brings the first phenolic resin onto the market under the name “Bakelite”.
1921
Principles of macromolecular chemistry resolved by Max Staudinger.
1922
BASF awarded a patent to manufacture urea-formaldehyde resins that were soluble in organic solvents.
1928
First production of polyvinyl chloride (PVC) in the USA; Production of polymethyl methacrylate (PMMA) as “Plexiglas” by Rohm & Haas.
1930
First industrial manufacture of polyvinyl acetate (PVAC), polystyrene (PS) and polyacrylonitrile (PAN).
1931
First stable plastic dispersion based on acrylic acid esters (BASF, Rohm & Haas) and vinyl acetate (Wacker, Hoechst); Start of production of polychloroprene.
1936
P. Castan (de Tre Frères, Switzerland) uses poly-addition to make plastics and invents epoxy resins that were patented by him in 1939. C. Ellis (Ellis-Foster Comp. USA) discovers the rapid curing of unsaturated esters and styrene by peroxides
1937
The polyaddition of diisocyanates and polyols to form polyurethanes (PUR) is based on the research work of O. Bayer in Leverkusen.
1940
IG Farben is awarded a patent for methacrylate adhesives (today “Agomet” of Degussa, Hanau).
1941
Large-scale production of saturated and unsaturated polyester resins.
1943
Manufacture of heat-resistant silicone rubbers; In the USA, the first use of phenolic resin – polyvinyl acet¬ates in formulations for metal-wood bonds in aircraft manufacture.
1946
Industrial manufacture of epoxy resins.
1953
V. Krieble (USA) introduces anaerobically curing adhesives based on dimethacrylate under the name “Loctite”.
1958
The first cyanoacrylate adhesives are introduced: “Eastman 910” in the USA and in 1960 “Sicomet” in Germany.
1967
First heat-resistant polyimide adhesives (up to 300°C) introduced in the USA.
1968
Start of development work on moisture curing poly¬urethane adhesives “Sikaflex” and “Betaseal” for sealing/bonding the front and rear windscreens on vehicles.
1970
Rapid further development of polyurethane chemistry with a wide range of 1-C (one component) and 2-C (two-component) adhesive for¬mulations; First UV-curing acrylate formulations; development of MS-polymers in Japan, application in earthquake-proof buildings.
1980
Reactive hotmelts.
1984
Development of anisotropic, conducting adhesives. The conductivity arises from direct contact of the substrates via individual filler particles (e.g. gold-coated polystyrene spheres / diameter 5 mm) in the adhesive matrix which do not touch and which are electrically conducting.
1988
Development of high-strength adhesives for bonding oiled steel sheets under industrial production condi¬tions (e.g. the car manufacturing industry). This in¬volved special hot curing 1-C epoxy resin adhesives.
From 1990
Development of various adhesives involving a com¬bination of curing mechanisms, e.g. cyanoacrylates which are initially cured by UV-light and then fully cured via the effect of moisture.
1993
Development of aerobically curing adhesives whose curing is triggered by oxygen. Hydroperoxide formers (e.g. hydrazone) are added to these adhesives. Under oxidising conditions peroxides are produced and start the polymerization.
1995
Development of silane-crosslinking polyurethane prepolymers (S-PUR) that complement the range of 1-C moisture curing rubber-elastic adhesives. They have an improved balance between reactivity and storage stability, there is no bubble formation and no longer function via an isocyanate-based reaction mechanism.
2000
Development of detachable adhesive systems for repair and recycling based on a change in tempera¬ture, stress, voltage and/or pH.
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