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7/27/2019 Brubaker - Crazy Glue
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Carrie Brubaker
Chemistry 30HJune 2, 2000
The Chemistry of Superglue
From its use in model planes to passenger planes, SuperglueTM is possibly the most well-
recognized example of the glue compounds. Indeed, any person who has unknowingly glued hisfingers together while using the product can acknowledge its remarkable (and insidious)
adhesive properties. The curing process that facilitates these properties is a chain polymerizationreaction. Although this process involves the contribution of fillers and stabilizers, the ingredient
that gives Superglue its adhesive ability is methyl cyanoacrylate. This compound is just onemember of a larger family of cyanoacrylates with the following basic structure:
C
C N
C O
O
R
H2C
Contrary to popular understanding, Superglue does not air dry. In fact, cyanoacrylates
in the compound cure (convert from liquid to solid) in the presence of weak bases such as water,alcohol, and blood. At normal conditions, a thin layer of water is present on almost all surfaces.This accounts for many unintended adhesions involving appendages and/or expensive tools! The
curing process involves the anionic chain polymerization reaction, which occurs as follows:
In the chain-initiating step, the weak base (X-
) donates an electron pair to a cyanoacrylatemonomer. The CH2 group is highly electropositive as a result of the electron-withdrawingproperties of the cyanide and ester groups; therefore, the electron pair is attracted to this region.
This attraction alters the carbon-carbon double bond to create bonding sites on both ends of thereactant group.
X-
+ H2C C
C N
C O
O
R
C O
O
R
C N
CH
2
X
In this manner, the electron pair is passed on in chain propagation as each monomer alters thenext. Bonds form between monomers, ultimately creating the powerfully adhesive polymer
chains of cured Superglue.
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Sources and References
Bound references:
Bikales, N.M.; Mark, H.F.; Menges, G.; Overberger, C.G.: Encyclopedia of Polymer Science and
Engineering, Second Edition. Volume 1, pp. 275-276, 290; Volume 2, pp. 17-20. JohnWiley & Sons, Inc., 1985.
Brown, W.H.; Foote, C.S.: Organic Chemistry, Second Edition. pp. 931-934. Saunders College
Publishing, 1998.
Web references:Chemfinder: www.chemfinder.com
Loctite Corporation: www.loctite.comJournal of the American Academy of Pediatrics: www.pediatrics.org
American Academy of Dermatology: www.aad.orgElmer s Products Inc.: www.elmers.com
www.ethiconinc.comwww.eff.org/pub/Publications/Bruce_Sterling/FSF_columns/fsf.07