Polycarbonate Sheet, Static Dissipative

Static dissipative polycarbonate bleeds charge away instead of holding it, for handling electronics and for anywhere a static discharge is a hazard. Published surface resistivity for the coated grades is 10^6 to 10^8 ohms per square by ASTM D257, which sits inside the dissipative band of 10^5 to 10^12 that the ESD classifications define, and static decay is under 0.05 seconds. Underlying mechanical properties are those of plain polycarbonate: tensile 9,500 psi ultimate on a 340,000 psi modulus, flexural 13,500 psi, compressive 12,500 psi, specific gravity 1.20.

Two things to know about the dissipative surface. It costs almost nothing in clarity - published light transmission is 88% at 3 mm and 85% at 6 mm with haze around 3%, on a par with plain clear sheet - but it is a conductive surfacing rather than a hard coat, published at pencil hardness 2B, so expect no abrasion resistance from it. And the temperature rating depends which product you get: one supplier publishes a maximum continuous service temperature of 180F for coated sheet and another 212F, both well below plain polycarbonate's 240 to 250F, while the carbon-filled stock shapes are published at 260 to 270F. If the part runs warm, tell us and we will confirm the figure for the lot.

Also worth knowing that two physically different products are both sold as static dissipative polycarbonate: a surface-coated type at 10^6 to 10^8 ohms per square, and carbon-filled stock shapes that span a much wider band, published at 10^5 to 10^10 and 10^7 to 10^10 - so the filled grades overlap the coated range from below rather than sitting above it. If you have an ESD specification with a resistivity window, tell us which band you need and we will confirm the type on the lot. Typical use is electronics assembly fixtures, machine guards and viewing windows on production equipment, tote and tray components, and cleanroom panels.

Chemical compatibility and cleaning, which is where most polycarbonate failures start. Clean it with mild diluted dish soap and a soft microfibre cloth, or an ammonia-free glass cleaner. Do NOT use ammoniated glass cleaner - the common blue kind - because ammonia attacks polycarbonate, and the resin maker's own testing shows 0.1% ammonia is enough to do damage in the presence of water. Also avoid abrasive or high-alkaline cleaners, scrapers and squeegees, dry rubbing, and solvent in direct sun. Isopropyl alcohol diluted 50/50 with water handles oil and tar. Acetone, MEK, methylene chloride, chloroform, toluene, xylene and aromatic fuels all attack it, and so do amines and the plasticisers that migrate out of flexible PVC - which is why PVC gasket, tape and cable tie contact is a real failure mode. The important subtlety is that chemical resistance is not a fixed property: stress cracking only develops where the part is in tension, so a cold-bent, over-torqued or tightly framed part will fail with chemicals a compatibility chart calls safe.