Description: Here's something you don't see every day: Kapton CR, 2 mil thick. Very hard to come by, like plutonium or unobtanium you can't just walk into a store and buy it, even online it's hard to find as usually manufacturers custom order it straight from Dupont as I ended up having to do as an individual since no reseller I know of stocks it, so not at all cheap at over $100 per lb in bulk 625mm rolls (heavy, about 55-60 lb each). THIS IS NOT COMMON AND RELATIVELY CHEAP KAPTON-HN, which is less than half the cost. So what is the difference that makes this more expensive but still worth it? Well, in short it's a trade secret but if I had to take an educated guess as an EE it uses silicon dioxide nanoparticles (quarts crystals, but less than 100nm in length and even thinner in width) as filler at around 10-20% by weight going by the 1.5-1.55g/cc density I crudely measured with cheap consumer-accurate equipment on hand vs pure Kapton-HN at 1.42 (quartz is almost 2x as dense as polyimide and along with ruby mica is among the most corona resistant materials known). What does that do? Well, for one it's 2x as thermally conductive as -HN but the selling point for me is it's corona resistance despite it'ss slightly lower dielectric strength of 6kV/mil vs -HN's 7kV. Short term dielectric strength and long term coronsa resistance/electrical durability are not the same thing. Put 1kVac on 1Mil -HN and it will fail/arc through in a few hours or so even when the dielectric strength is 7x that. Same conditions (1kV /mil) with -CR lasts over 100x longer. And since when it comes to any organic polymer (plastic) long-term reliabilty heavily depends on voltage stress (roughly to the 7th power, so what lasts x hours at 1kV/mil will last 128x hours at 500v/mil). Anyway, story behind it is I bought this for my personal experimentation (which requires very high voltages, MV's) and this is going into the cascaded transformers to reduce size and weight (150kVA 1A each = 1-2 tons with the usual oiled paper and 60Hz vs 100kHz with -CR under oil = about 50-60lb for same power, voltage and expected lifetime). Well, I didn't need the whole pallet I bought, so selling the extra here per linear foot at $10 for the 625mm width, $3 for the 185mm, and $1.80 for the 110mm (an example of each pictured). If over 100 feet is ordered I can do a bulk deal and sell it at around $150 per pound if you want a bunch at once (each roll is about 1600 feet in length and the per pound cost is about half the length cost, apparently eBay won't let me list the 20,000+ feet I have all at once due to their monthly limits). $20 shipping to USA, actual shipping cost + you pay customs fees, if any, for international (which can be quite high if you're in a country with high tariffs on PI film and/or USA as origin country, best to check before buying). Will be sent either USPS ground or Priority depending on cost (my choice, faster method all else equal). Also this won't be just folded up and stuck in an envelope like some sellers do while hoping for the best (have gotten a few broken/wrinkled items sold to me way). Smaller orders will be rolled up into a 2" tube mailer. Larger orders will use a 2" tube mailer as a core and put into a 3" mailer (I'd guestimate about 5-10 lbs will fit this way, depending on width).
Price: 3 USD
Location: Cincinnati, Ohio
End Time: 2024-10-26T21:14:38.000Z
Shipping Cost: 20 USD
Product Images
Item Specifics
All returns accepted: ReturnsNotAccepted
Brand: Dupont
Type: Mixed Lot
Unit Type: ft
Model: CR200
Country/Region of Manufacture: United States
Unit Quantity: linear foot
California Prop 65 Warning: For once here's something that DOESN'T cause cancer in California but is fine most everywhere else.
