They are often used as primers under other materials that have good barrier properties but marginal adhesive characteristics. Coating thickness can vary from 1 mil for light-duty protection to as much as 20 mil for service involving the handling of corrosive chemicals or abrasive materials. Performance of epoxies is limited in the heavier thicknesses, however, because they are more brittle than other organic materials. Nylon 11 coatings provide attractive appearance as well as protection from chemicals, abrasion, and impact. Applied by electrostatic spray in thicknesses from 2.5 to 8 mil, nylon coatings are used on office and outdoor furniture, hospital beds, vending-machine parts, and building railings.
Fluorocarbons are more nearly inert to chemicals and solvents than all other polymers.
PTFE, FEP, and PFA are also suitable, but they have a greater tendency to creep under load. For abrasive conditions, PVDF is outstanding among the fluorocarbons. These materials are also used on engine components and welders. PVDF also has the highest compressive strength of the fluorocarbons. Coatings based on PTFE are being used to reduce wear in the U.S. automotive industry.