Acetone is a common organic compound, often found in nail polish removers and used as a solvent in various products. While it does not corrode plastic like an acid on metal, its effect depends entirely on the specific type of plastic it encounters.
How Acetone Affects Plastics
Acetone functions as a solvent, dissolving or softening other substances. When it contacts plastic, it interacts with the polymer chains that form the plastic’s structure. This disrupts the weak intermolecular forces holding the polymer molecules together. Acetone molecules intersperse among the polymer chains, causing the plastic to swell, soften, or even dissolve. The degree of this effect is determined by the plastic’s unique chemical makeup.
Plastics That Acetone Damages
Certain common plastics are highly susceptible to damage from acetone, often leading to dissolution or significant structural degradation. Polystyrene (PS), frequently found in disposable foam cups, packing peanuts, and CD cases, readily dissolves when exposed to acetone. Polyvinyl Chloride (PVC), used in items like pipes, some toys, and certain packaging, can be severely affected by acetone; prolonged exposure can soften, smear, or even dissolve PVC, compromising its integrity. Polycarbonate (PC), a strong, clear plastic used in CDs, DVDs, some water bottles, and safety glasses, experiences softening, surface cracking, and clouding when exposed to acetone, leading to a loss of optical clarity and structural strength. Acrylic (PMMA), known for its use in plexiglass and clear containers, will soften and can develop cracks or a cloudy appearance upon contact, sometimes even dissolving.
Plastics That Resist Acetone and Safe Use
Fortunately, many plastics exhibit strong resistance to acetone, making them suitable for containers or applications where acetone exposure is possible. Polyethylene (PE), found in plastic bags, milk jugs, and chemical bottles, is generally resistant to acetone. Polypropylene (PP), commonly used for food containers, bottle caps, and some automotive parts, also shows good resistance. Fluoroplastics like PTFE (Teflon) are highly resistant to a broad range of chemicals, including acetone.
When working with acetone around plastics, exercise caution. Always test acetone on an inconspicuous area of the plastic first. Use acetone in a well-ventilated area due to its flammability and strong vapors. If the plastic type is unknown or susceptible to damage, consider alternative cleaning agents or solvents. Even resistant plastics can be affected by prolonged exposure, high concentrations, or elevated temperatures, so limit contact time.