Repurposing Styrofoam


melted styrofoamThat white styrofoam we use for packaging, coffee cups and other things can be repurposed into a wide range of things.  When Styrofoam is mixed with gasoline or other chemicals it will breakdown into a gooey glob that when dried will be a hard plastic instead of the light fluffy stuff we think as styrofoam.  Styrofoam is made from a common plastic called polystyrene and it mixed with air.    It can be formed into all kinds of useful things while it is a goo.  It can be molded and formed.  While it is a goo is it is very sticky and can be used as a glue or sealant.  It takes very little of the gasoline or other liquid to “melt” the styrofoam.    While a goo it is very flammable and is very similar to napalm.  It can take a few days for the goo to become solid again.  The liquid must evaporate.  It can be used to seal small roof holes and seal cracks.

When you mix Styrofoam (extruded polystyrene) with gasoline or acetone, the Styrofoam breaks down. Styrofoam is a chemical of petroleum base that is fluffed up like cool whip, when it dissolves in gasoline it changes back to a liquid. All the air inside escapes, and it becomes a wet, gooey mess.  If left out to dry, it gets hard again, but not like before, without the air – it resembles hard plastic. Polystyrene itself is a hydrocarbon, which means it is made up only of carbon and hydrogen atoms bound together.

What  chemicals will desolve Styrofoam?

  • Limonene – is a chemical in the juice squeezed from the peel of oranges or lemons.
  • Benzene – Polystyrene, the plastic used to make styrofoam, contains benzene, a strong organic solvent. Benzene will dissolve styrofoam. Though benzene is a hazardous, carcinogenic substance, it is useful as an industrial chemical, helping to produce plastics, rubbers, detergents and drugs.
  • Toluene – A chemical cousin of benzene, toluene sees use as paint thinner, an octane booster in gasoline and a
    chemical feedstock used to produce other substances. Since it is less toxic, toluene has replaced benzene in most nonindustrial uses.
  • Acetone – is an organic solvent found in nail polish remover, will dissolve styrofoam. The acetone does not chemically destroy the polystyrene; it simply causes the tiny bubbles in the foam structure to come apart. The polystyrene remains, though dissolved in the acetone. If you let the acetone evaporate, it will leave a clump of solid polystyrene behind.  Acetone will make a almost clear plastic when dried.
  • Gasoline – The same gasoline you put in your car will dissolve styrofoam, though it will not dissolve some other plastics, such as polyethylene. Unlike toluene and benzene, which are pure substances consisting of a single molecule, many different compounds go into making gasoline, including hydrocarbons and additives.  Gasoline makes the resulting plastic a little milky.
  • For an extensive list of plastics and solvents click here.



Polystyrene is an aromatic hydrocarbon, it has several complicated double covalent bonds and is a chain of styrene molecules (C6H5CH=CH2) which is very unsaturated. Gasoline is made up of an assortment of simple aliphatic hydrocarbons such as ethane and isobutane, and some aromatic hydrocarbons added as enhancers, as their break-up generates more energy.  When you drop polystyrene into gasoline; the high energy bonds in the aromatic chain break in favour of simpler single covalent bonds. The  end effect is that the mass of polystyrene breaks apart releasing the trapped air, and forms into a mass of new hydrocarbon chains, which forms some fort of amorphous solid, a slimy film of the Ethane-styrene bonded chains and gasoline. There shouldn’t be any gases released which are any different from the vapours off of the original gasoline. You are only in trouble when you burn it, this is when it starts to bond with oxygen forming things like carbon monoxide.

Styrofoam is a massive problem in the developing world.  It does not naturally degrade and will last for years.  River and the land are littered with it.

styrofoam trash in HaitiIn the nation of Haiti, despite two government decrees making their import and usage illegal, styrofoam cups and plates are used and littered all over the capital, as well as bought and sold, wholesale and retail, completely out in the open. The first decree, dated Aug. 9, 2012, went into effect on Oct. 1, 2012, as part of a decree that also outlawed black plastic bags, used by street vendors as well as in greenhouses all over the country.  In 10 months since the ban  there is little to suggest that  the new decree will bring about much change. The streets of the capital region are awash in styrofoam. Any passerby, police officer, or state official can see bright white products, as well as the illegal black plastic bags, being used and discarded everywhere.

In california people throw away 300,000 tons of styrofoam every year. Considering how little styrofoam weights the volume of the waste is staggering.  Styrofoam litters the oceans.  The Great Plastic Patch in the pacific ocean features three million tons of plastic debris floating in an area larger than Texas. An eye-popping 46,000 pieces of plastic float on every square mile of ocean! Humans toss another 2.5 million pieces into our oceans hour.