Peroxymonocarbonate and Percarbonate (Hair bleach or clothes bleach? Why can't it be both?)

Everyone by now has tried products like OxiClean, or detergents with "oxygen bleach." Rather than sodium hypochlorite, which is found in regular bleach, they've got sodium percarbonate, which is actually a mixed crystal of sodium carbonate (the old-timey name of which is "washing soda") and hydrogen peroxide. In solution, they form a "peracid," peroxymonocarbonate.

Speaking very generally, a bond between two electronegative atoms is the business end of an oxidant - the oxygen-oxygen bond in hydrogen peroxide and peroxymonocarbonate does the job there, and the oxygen-chlorine bond is the pointy end of hypochlorite. With oxidants, though, it's like Derek Lowe said about Lewis acids:

To a good extent, those reagents parallel Tolstoy's quote from Anna Karenina, in that protic acids are all alike, but every Lewis acid is an acid in its own way.

Peroxymonocarbonate is a sufficiently benign oxidant that it's safe for many dyes in clothing that hypochlorite would tear apart. Similarly, it has been used by Procter and Gamble to good effect in hair coloring. It is an effective oxidant, but works mechanistically a little differently and at a more mild pH than peroxide. Thus, they claim less damage to hair fibers and the lipid coat on your hair - presumably making freshly dyed hair feel less like dry straw.

This isn't to say that peracids are always the friendliest of oxidants - back in the '90's, a detergent additive called Persil Power used a manganese additive to boost the bleaching power of peracids. Manganese-peroxide chemistry is well-known. For instance, you probably saw a demo in some science class at some point where a dash of manganese dioxide catalyzed the rapid decomposition of hydrogen peroxide. The manganese-peracid additive worked too well, though. After a few washes, clothes started falling apart! Unilever had to go back to the drawing board and reformulate, as well as go through a pricey recall - when you take developing the new product into account, it was nearly a half-billion dollar mistake! Who knew soap could be so serious?

Thanks to Jennifer Marsh for passing along information on peroxymonocarbonate in hair dyes.

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Cool. I've been using an OxiClean knockoff for laundry when chlorine bleach isn't needed.

I keep hydrogen peroxide (and vinegar) in the kitchen for disinfecting fresh produce, and washing soda to remove wax and grease. I keep a bottle of a saturated solution of washing soda for quickly cleaning excess skin oil off my hands or anything that's oily but not dirty.

Sadly, I didn't really learn anything useful about chemistry until I was out of school.

1) Solid peroxycarbonate plus pigment aluminum powder - hyper-thermite boom?

2) Fatty acid sodium or potassium salt plus aluminum powder - aluminothermy giving residual carbon as diamond? Longer alkyl chain gives smaller reaction enthalpy.

(2) is a nice high school science project. It might not be successful but it wouldn't be boring.