Posted on by Carl Marchese
Is Polycarbonate Resistant to Isopropyl Alcohol?
Quick answer
Sometimes—but not under every condition. Brief wiping with a dilute isopropyl-alcohol solution may be acceptable for some polycarbonate grades, while repeated exposure, high concentrations, long contact times or contact with stressed plastic can cause crazing or environmental stress cracking. Check the exact resin or enclosure manufacturer’s chemical-resistance data and test the real application.
Why online compatibility charts disagree
“Polycarbonate” describes a family of materials, not one universal formulation. Resin grade, colorants, flame retardants, UV packages, molded-in stress and processing history can change chemical resistance. Charts may also use different concentrations, temperatures, exposure times and pass/fail criteria. A rating based on a quick room-temperature wipe does not establish suitability for continuous immersion or repeated sanitation.
The main risk: environmental stress cracking
Alcohol exposure may not dissolve polycarbonate, yet it can accelerate cracking in areas under stress. Stress can come from tight screws, forced assembly, sharp inside corners, machining, bending, impact or residual molding stress. Fine surface crazing may appear first, followed by loss of impact performance or a larger crack.
Questions to answer before using IPA
What is the IPA concentration? Is exposure a single wipe, repeated cleaning, splash, vapor or immersion? How long will the surface remain wet? What temperatures are expected? Is the enclosure loaded, bent or tightly fastened? Does the product contain other solvents, fragrances or quaternary ammonium compounds? The complete cleaning formulation matters, not just the active ingredient named on the label.
Safer evaluation steps
Obtain compatibility guidance for the exact enclosure material. Test an actual finished part or representative sample under realistic mechanical stress. Use the intended cleaner concentration, dwell time, wiping method, temperature and number of cycles. Inspect for clouding, crazing, swelling, tackiness, discoloration and loss of strength. If the exposure is critical or continuous, ask the manufacturer for written application guidance.
Cleaning polycarbonate enclosures
Use the mildest effective cleaner and a soft, nonabrasive cloth. Do not assume that stronger concentration improves safety or cleaning performance. Avoid mixing chemicals. Prevent cleaner from pooling around fasteners, hinges, seals or machined openings, and rinse or dry the surface if recommended by the chemical and enclosure manufacturers.
Bottom line
Polycarbonate should not receive a blanket “resistant” or “not resistant” label for isopropyl alcohol. Limited exposure may be acceptable for a specific grade, but environmental stress cracking makes application-specific verification essential. For Fibox products, consult the current chemical-resistance information and contact technical support when the concentration or exposure is severe.
Contact Fibox to learn more, and let's keep your vison true!.
Sources for technical review
Covestro: Compatibility with Disinfectants: https://solutions.covestro.com/-/media/covestro/solution-center/whitepapers/cov-chemical-compatibility-to-disinfectants-used-against-sars-cov-2-2020-06.pdf
Fibox Chemical Resistance: https://www.fiboxusa.com/chemical-resistance/