Ugly is okay ....thanks for the tips
Does anyone make 10 or 20mil EDPM ?
99guspuppet


> On Dec 29, 2011, at 11:59 PM, RussellMc wrote:
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> What isyour application?
> Does it have to look pretty?
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> I'd expect no UV protectant if not stated but not certain.
> I'd expect " few years" with no UV protectant and a few years with (OK
> maybe 3-5.)
> NZ is VERY harsh UV wise.
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> If there is  a will to do so you could make plastic sheet last much longe=
r
> than it probably will.
> Probably 10-15 years if you really wanted.
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> UV protectants diffuse out of the target material with time, setting one =
of
> several upper limits on lifetime
> Real people blow multiple layers of disparate plastics as an apparent
> single sheet to get desired results.
> 2 & 3 common. 4 I've seen. More + may exist.
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> Probably PE.
> May be PP - lss likely.
> May be other but less likely again.
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> You want both a UV stabiliser turned to the absorbtion peaks of you plast=
ic
> AND a HALS (hindered amine light stabiliser) that absorbs the breakdown
> radicals when they do occur.
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> You want to see what BASF have to say.
> They are THE biggest chemical company in the world and know their IV stuf=
f.
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> CIBA Geigy were very very good too - but BASF bought them about 2 years a=
go.
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> CIBA do the Tinuvin range of UV protectants.
> Beware the "like Tinuvin xxx" or same formula as Tinuvin xxx.
> This may in fact be true but even then they seem to get better results.
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> All "identical" plastics are not created equal
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> The wonderful Gaisma
> Nothing on UV but adds to your information base.
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>        http://www.gaisma.com/en/location/denver-colorado.html
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> Altitude 1600m will have some effect.
> You'd expect an increase in clearaness factor from that but the 0.5x or s=
o
> isn't stunning.
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> Here's Bamiyan for comparison
> http://www.gaisma.com/en/location/bamiyan.html
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> Kudahuvadhoo
> http://www.gaisma.com/en/location/kudahuvadhoo.html
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> Both chosen for hoped for clearness factor.
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> Oh yes!
> Amundsden-Scott - 0.73!
> http://www.gaisma.com/en/location/amundsen-scott--permanent-station-of-th=
e-us.html
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> Denver
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> Variable I II III IV V VI VII VIII IX X XI XII
> Insolation, kWh/m=B2/day 2.03 2.87 4.06 5.09 5.87 6.34 6.28 5.50 4.56 3.4=
3
> 2.37 1.88
> Clearness, 0 - 1 0.49 0.51 0.53 0.53 0.54 0.55 0.56 0.55 0.55 0.54 0.52 0=
..50
> Temperature, =B0C -3.00 -1.25 2.80 7.27 13.00 17.55 20.72 19.29 14.95 8.4=
0
> 0.90 -3.31
> Wind speed, m/s 8.01 7.57 7.54 7.45 6.64 6.01 5.48 5.51 5.97 6.46 7.00 7.=
61
> Precipitation, mm 13 18 34 42 71 40 53 40 30 24 22 15
> Wet days, d 5.5 5.9 8.7 8.1 10.5 8.7 9.3 9.3 6.9 5.0 5.4 6.0
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> On 30 December 2011 09:22, YES NOPE9 <yes@nope9.com> wrote:
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>> If a roll of 6 mil black plastic does not say it is UV resistant .......
>> Does one presume it is not ?    If it does say it is UV resistant,
>> what kind of lifetime will it have in Denver, CO ?  ( sunny most days ,
> high altitude )
>> 99guspuppet
>> --
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