Hi wondermom,
Thank you for an interesting question.
MadSci Network: Chemistry
http://www.madsci.org/posts/archives/dec2000/976306105.Ch.r.html
Re: How does nail polish remover remove nail polish?
"Before I answer the question, let me say that there are several
answers posted on MadSci that answer the question concerning the
ingredients of nail polish and nail polish remover (What are the
ingredients in fingernail polish?, What chemicals affect nail polish
durability?, fingernail polish science fair, and What chemical in nail
polish causes it to dry fast?). I will repeat some of what I learned
from those questions/answers here. The three main types of ingredients
in nail polish are (1) organic solvents and drying agents, (2)
thickeners and hardening agents, typically polymeric species such as
polyester-urethanes resins or styrene/acrylic copolymers, and (3)
coloring and other agents to provide certain colors and effects such
as shine.
Now to answer the question you asked concerning the chemicals and
chemical reactions that make nail polish removal possible. Here's the
beuaty of the entire thing- there is no chemical reaction. The nail
polish remover is just the organic solvent that is used as an
ingredient in the nail polish. That is, ingredient #1 above is sold as
a "pure" material (meaning that ingredients 2 and 3 are not present,
but that does not mean that other chemicals are not present to save
costs). The hardened nail polish is dissolved by the nail polish
remover (basically putting it back into the form that it was in when
applied to a nail). For dissolution to occur, no chemical reaction
takes place. However, what is necesary is that the solvent likes the
polymer. There is a rule of thumb that may be a bit oversimplified,
but it works, and that is "like dissolves like." And in this case, it
can really be oversimplified and said that the organic polymer that is
the hardened polish on a nail can be dissolved by an organic solvent
(by no means an exact rule, but it usually gives one a good starting
point). So if a solvent likes the polymer, as is the case for nail
polish and nail polish remover, the solvent molecules (which may be
ethyl acetate or acetone, two organic solvents) get in between the
polymer chains and "push" them apart. There are so many of the solvent
molecules pushing the polymer chains apart that eventually the polymer
chains do not know that other polymer chains exist and you get a
solution. This solution can then be wiped off with a cotton ball or
tissue when nail polish is dissolved by nail polish remover. Next time
you remove nail polish (or see someone remove nail polish), look at
the cotton ball or tissue, eventually the solvent will evaporate
(similar to the drying process as to when one is painting their nails)
and leave a hardened residue on the cotton ball. This
dissolving/evaporating process is endless (for the most part) so that
if you can collect the dissolved nail polish, you could use it over
and over as long as you have a solvent."
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Best regards and good luck with the Science Fair Project,
tlspiegel |
