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pompeii -> RE: superglue (8/30/2008 3:40:05 AM)
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<nerd warning>
A little-known fact about cyanoacrylates liquid polymerizable adhesives is they can't bond on perfectly dry surfaces. Why? Because they chemically link (polymerize) when pressed into a thin film - that polymerization being catalyzed by the very thin layer of water moisture present on most surfaces (the moisture acts as an alkali, or weak base, which is the catalyst that results in the exothermic hydroxylation reaction we call bonding).
For human use, it's important to note that the presence of detectable amounts of water (i.e., too much) usually degrades the performance of cyanoacrylates, so, that might preclude using acrylic resins to lash her tongue to her kitty, I guess, for example ... at least if she's excited beforehand. Stick to more typical methods. Like Bondo.
A more well known fact is, as cyanoacrylates cure (polymerize), they give off a vapor that can irritate the nose and eyes and will "spot" many materials, especially plastics - so be careful around the face because your retina will permanently be damaged by the gassing.
Also, typical cyanoacrylates (e.g., Super Glue, Crazy Glue, Loctite, Insta-Bond, etc.) are best used in molecule-thin layers because, while the bonding (polermization) strength is phenominal, the material itself isn't very strong. So, if you pile the glue on too thickly, you end up with the two objects parting between layers of the glue.
BTW, periacryl cyanoacrylates (e.g., Blacklock Medical Products, Delta, B.C.) have been used in surgery since the 1960s. They're not only good adhesives, in the body they're hemostatic and bacteriostatic. As for toxicity, shorter-chain cyanoacrylate derivatives tend to have a higher degree of tissue toxicity than the longer-chain derivatives do. In contact with human tissue, they degrade to cyanoacetate and formaldehyde. In addition to surgical uses, in the beginning of 2001, the US FDA approved the use of 2-octyl cyanoacrylate (i.e., Dermabond) for use as a barrier against bacteria.
</nerd warning>
And, as stated, acetone (e.g., nail polish) or even hot water will help unstick those sticky fingers.
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