> > > > I'm told that fluor ethylene vinyl ethers (FEVEs) are the best = bet
> > > > > when you want long term (30 year) fade resistance. I need = something
> > > > > with zero-little maintenance requirements. I just couldn't get = over
> > > > > how expensive this stuff really is. One brand, Lumifon, goes = for
> > > > > about $15/lb. I find it hard to believe there isn't anything = out
> > > > > there for less money that works almost as well. I'm concerned = that at
> > > > > these prices, the job won't fly.
> > > > >=20
> > > > > Can anyone share some knowledge in this area?
> > > > >=20
> > > > > Phil
> > > >=20
> > > > Actually, FEVE's have slightly inferior weathering to =
PVDF/acrylic
> > > paints. In the USA, these paints are available from PPG, = Valspar, Akzo
> > > > Nobel, and BASF. Please note that PVDF/acrylics are factory = applied
> > > > finishes (that is, they are coated on metal by coil or spray = coating
> > > > methods then baked in a oven prior to installation of the panels = in
> > > > the field). If you need a field applied finish on an existing
> > > > building, then you have to stick with FEVE's like Lumiflon (sold = by
> > > > PPG as Megaflon in the USA).
> > > >=20
> > > > PVDF resins are available from Solvay Solexis (as Hylar 5000) = and
> > > > AtoFina (as Kynar 500) and have demonstrated more than 35 years
> > > > excellent weathering performance. PVDF/acrylic paints are about = 3 to
> > > > 4 x cheaper than FEVE-based paints. FEVE weathering is worse due = to
> > > > the high content of hydrocarbon monomers (lower fluorine content = than
> > > > PVDF).
> > > >=20
> > > > If you need more information, you should contact the paint = companies
> > > > mentioned above. If your application is not a paint but instead = a film
> > > > or other type of dry coating method, then you should contact = Solvay
> > > > Solexis or AtoFina for assistance in selecting an appropriate = coating
> > > > system. Someone else mentioned Du Pont's Tedlar film which is = PVF
> > > > (polyvinylfluoride). It has less fluorine than PVDF and has been = shown
> > > > to have significantly worse weathering performance than PVDF. > > > >=20
> > > >=20
> > > > - Bill
> > >=20
> > > Phil:
> > > As someone mentioned, without knowing your application, it's hard = to
> > > provide useful input. Having said that, you are probably talking
> > > about powder coatings, where FEVE is the only commercially = available
> > > fluorocarbon for 30+ year durability in architectural =
applications.=20
> > FEVE powder is a factory applied finish and is often used on
> > > prefabricated building components. You can visit the following = link
> > > to learn more about Spraylat's new FEVE based powder product = (Newlar)
> > > which is available in a variety of colors.
> > >=20
> > >
formatting link
> >=20
> > > Akzo also offers an FEVE based powder called "Interpon D3000"
> > > (see
formatting link
> >=20
> > > Other companies also sell similar FEVE powders.
> > >=20
> > > Other fluorocarbon based powder coatings include Ausimont's ECTFE
> > > (tradename Hylar I believe), PTFE (available from DuPont & Asahi
> > > Glass) and DuPont's PVF (tradename Tedlar, already mentioned).=20
> > > However, these products may not have sufficiently good weathering
> > > characteristics for architectural paints.
> > >=20
> > > Tribo
> >=20
> >=20
> > Tribo,
> >=20
> > Thanks for the input. However, a few corrections are needed. First,
> > PVDF is also available as a powder coating, so it can be used as = both
> > an architectural powder coating and an industrial corrosion =
resistant
> coating (like inside a tank). You still get the 35+ year performance
> > of PVDF in the powder form as found in the PVDF/acrylic organic
> > dispersion coatings.
> >=20
> > Powders have not really caught on. The solvent based coatings can be
> > factory applied by coil or spray techniques and all the coaters now
> > have incinerators/afterburners to address the potential =
environmental
> issues of a solvent-based system. The very high cost of the powders
> > has been the limiting factor. If the Spraylat product mentioned = above
> > is closer in cost to liquid PVDF formulations, it could be
> > competitive.
> >=20
> > ECTFE is sold under the brand name HALAR by Solvay Solexis (formerly
> > Ausimont). Also, PTFE is available from several other companies,
> > including Daikin, Dyneon, and Solvay Solexis. You should also = mention
> > ETFE powder coatings available from Du Pont, Asahi Glass, and Daikin
> > which are similar in cost and performance to ECTFE.
> >=20
> > Weathering of partially fluorinated polymers like ECTFE and ETFE is = in
> > the same range as PVDF, but they lack the ability to be formulated
> > into organic dispersions for paints and are limited to relatively
> > high-cost powder application. There is a large difference in the = cost
> > of fluoropolymer powder coating resins and the well-known organic
> > dispersions made with 70:30 PVDF:acrylic.
> >=20
> > - Bill
>=20
> Bill & Tribo - you guys sound like you really know what you're talking
> about. I really appreciate the help!
>=20
> Since I've got no experience with fluoropolymer paints, let me make
> sure I've got this right so I make the best decision. Let's say I
> formulate a 70% fluorpolymer based paint (FEVE or PVDF). What I'm
> hearing is that the FEVE based paint cost 3-4x that for PVDF based
> paint. I'll assume the raw material cost is proportionate. So that
> would put PVDF at $4-5/lb (vs $15/lb for FEVE). From experience, I
> know acrylics are dirt cheap, so the cost of the dispersion would be
> ~$3-4/lb. Assuming the powder costs 3-4x(??) as much as the
> dispersion, the powder would cost maybe $12-15/lb. Is that how it > works?
>=20
> Thanks
> Phil
>=20
PVDF is normally formulated with 30% acrylics. This gives optimum properties in terms of adhesion (natural PVDF won't stick to metal so well), pigment dispersion in the paint, and physical characteristics of the coating (impact resistance, etc.). FEVE's do not use acrylic because they are already about 50% of functional hydrocarbon monomers that give the same effects of acrylic in a PVDF paint. This is also why FEVE's have somewhat inferior weathering compared to PVDF/acrylic (higher hydrocarbon content, lower fluorine content so faster photodegradation).
I can't precisely confirm the prices you listed. You need to speak with the paint companies that formulate PVDF/acrylic and FEVE's into paints. As I recommended earlier, try PPG, Akzo Nobel, BASF, and Valspar.
For powder prices, you can check with the various suppliers noted earlier in the thread. PVDF powders will be the least expensive and things like FEVE, ETFE, ECTFE, etc. will be much higher as powder coatings.
- Bill