Friday, September 15, 2017

water - Is there a type of detergent/surfactant that evaporates at STP?


Are there any type of detergent/surfactant chemicals that would be good for removing dirt and grease from fabric that also would evaporate from the clothes within, say, 24 hours leaving no residue?



Googling "volatile surfactant" turned up fluorocarbons and something called Surfynol 61, which is really 3,5-Dimethylhex-1-in-3-ol as possible candidates. I don't know if these would be safe for laundry.



Answer



Volatile surfactants


There are many molecules that are both surfactants (in water) and volatile, but of the ones I can think of, none can be used safely in home laundry applications.




  1. Hydrocarbon derivatives. The examples you found by googling are in this class. 3,5-dimethyl-1-hexyn-3-ol is the principal component of Surfynol 61 (probably named Surfynol 61 because it is a surface-active (surf) alkyne alcohol (ynol) with six carbons (6) and the alkyne moiety at carbon one (1). Other examples would be medium-chain fatty alcohols like hexanol, octanol, cyclohexanol, etc. These molecules reduce surface tension of water and have OK-ish cleaning power (not as good as larger but non-volatile alternatives like SDS), but their volatility is also their downfall: their use in home environments creates a strong fire and explosion hazard when used in automatic heated dryers.




  2. Fluorocarbon derivatives. I found the same article you probably did about volatile fluorocarbon surfactants. The most powerful at reducing the surface tension of water seems to be nonafluoro-tert-butyl alcohol, which reduces water surface tension by 78%! However this experiment required saturating the water with the vapor of this compound. And 1 gram costs >$80. And toxicity is a concern, despite this compound apparently being researched as a component of or precursor to artificial blood mixtures in the 1970s.





  3. Other halocarbon derivatives. These include solvents like perchloroethylene, chlorobutanol, etc. These are all highly toxic, and with some of them, there is a flammability/explosion risk as with hydrocarbon derivatives.




Non-surfactant use


You might consider just using organic solvents that are not (very) surface active as a way to degrease fabric. However, these may leach dyes out of the fabric or otherwise damage them. Isopropyl alcohol (IPA) is accessible to home users, and is relatively safe. Be sure to do the soaking in a well-ventilated area, and do not use heated dryers to remove the IPA! Instead, rinse out the IPA thoroughly with water. Depending on local regulations, you will have to dispose of all of the dirty IPA and IPA-contaminated rinsing water as solvent waste.


The best option


Pay to have your clothes dry cleaned!


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