Of all the gimmicks out there used to sell car parts to the public at large, Polytetrafluoroethylene -- aka PTFE or Teflon -- coating is probably one of the few that actually lives up to its advertising. It's not a perfect material for use in harsh environments, like those that wheels typically encounter, but it does have certain advantages over paint or raw-finished metal.
PTFE is a synthetic polymer that consists almost entirely of carbon and flourine. Flourine provides the powerful electronegative force responsible for PFTE's non-stick qualities. Most of us are familiar with Teflon-coated cookware, but this substance sees a lot of use in the industrial sector. PTFE's relatively high melting point of 620 degrees Fahrenheit, its ability to "creep" and seal small cracks and its resistance to friction and damage via corrosives make it invaluable in certain harsh industrial environments.
Aside from its appearance and gadget value, PTFE helps keep dirt, mud and brake dust from adhering to the rim. Water introduced onto the rim will slip in between any dust and debris that does stick; the contaminant will "stick" to the water better than it does to the Teflon, making the rim far easier and quicker to clean. Teflon-coated rims are a popular item among off-roaders who can afford them, particularly those who spend a lot of time in the mud.
Teflon is dark gray in color, somewhere between gunmetal gray and charcoal black. It has a slightly metallic, semi-gloss finish, like cast aluminum, but is smooth to the touch. Teflon is softer than aluminum, with a Rockwell hardness of R58, but harder than copper and most kinds of wood. Being a polymer, it's naturally a bit more flexible than steel, which is a good thing where durability is concerned. All Teflon-coated rims aren't created equal, and you get what you pay for. The thicker the PTFE coating, the better it will resist scratches and nicks from road debris and rocks.
If you've already got a set of rims, then you've got a couple of options. If they're aluminum, then you can polish the rims to get them smooth and keep a coat of wax on them at all times. Alternatively, you can purchase a PTFE paint additive and paint them yourself, or you can coat them with pure Teflon just like any manufacturer does. Teflon coating works similar to powder-coating, and it's an economical option if you've got the equipment and want the benefits of Teflon but don't want to spend $150 a pop or more on new rims.
