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Hot Stuff, How |
R W Stuart 5/19/99 Hot Stuff, Crazy Glue, Instant Glue, et al are all almost pure ethyl-2- cyanoacrylate, a rather simple molecule which polymerizes very rapidly in the presence of moisture. The liquid glue polymerizes almost instantly to a hard and brittle acrylic plastic. A fragile double bond exists between two of the six carbon atoms in each molecule of fluid glue, and the glue remains fluid as long as the double bond exists. The double bond is easily broken by the hydroxyl ions found in most airborne moisture. The double bond becomes a simple bond and the now free extra bond allows the molecules to form long chains of the now single bonded molecules. The result is the solidified acrylic resin. Ethyl-2-cyanoacrylate forms a polar molecule and polar materials attract one another by bringing their polar charged areas as close together as possible, Adhesion is good because most surfaces are also polar and the glue sticks tightly to them. Hot Stuff containers and delivery tubes are made of polyethylene- a waxy plastic which is mostly nonpolar and does not stick to the glue. The containers also prevent massive exposure to moisture and the hydroxyl ions required to break the fluidizing double bond of the virgin fluid glue. The obnoxious gassing which accompanies curing results from breakdown of the cyanoacrylate due to heating during cure. The breakdown products are indeterminate, but may be any mix of carbon and nitrogen- the basis of the various poisonous cyanates. The gasses are not to be breathed. Nitromethane is one debonder.
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H H O H H is hydrogen, C is carbon, O is
| | | | | oxygen, N is nitrogen
Fluid: H--C--C--O--C--C==C Note double bond, ==, in the fluid
| | | | ethyl-2-cyanoacrylate. The N--C
H H --| H bond is a triple
N--C
--
----------------------------------------------------------------------Hydroxyl
Ion: H--O--H (water) becomes H+ and -OH (hydroxyl ion)
in airborne water vapor
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H H O OH <-- hydroxyl ion | | | | | Fluid with broken bond: H--C--C--O--C--C--C | | | | <-- free extra bond H H N--C H H O | | | | | <-- Free bond H--C--C--O--C--C--C | | | | Polymer chain with H H N--C | three molecules | shown H H O | | | | | | Note that the hydroxyl Polymer chain: H--C--C--O--C--C--C ion (-OH) does not | | | | enter into the chain- H H N--C | it breaks the double | bond and moves on to H H O | the next fluid | | | | | molecule H--C--C--O--C--C--C | | | | <-- Free bond H H N--C
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