Moldable and durable polymer with excellent UV characteristics
Moldable and durable polymer with excellent UV characteristics
(OP)
I am trying to find a polymer that can be exposed to high doses of UV constantly (tens of mW) without degredation to the polymer. I also need the polymer to be mechanically robust. Previously i have used some elastomers but they degrade and their mechanical properties fail quickly. I am not sure i need an elastomer. Are there elastomers that can withstand high UV doses? If not, what other polymers would be useful to try?
Thank you for your help.
Best,
adam
Thank you for your help.
Best,
adam





RE: Moldable and durable polymer with excellent UV characteristics
PMMA (Lucite/Perspex) is transparent to UV.
uPVC is also good with UV, although I am not sure about plasticised elastomeric flavours...
Polyesters are also good with UV (PBT/PET etc)
Cheers
Harry
www.tynevalleyplastics.co.uk
RE: Moldable and durable polymer with excellent UV characteristics
PET is very good but still needs stabilisers that are sacrificial in normal circumstances.
Does it need to be transparent or a specific colour?
PTFE (Teflon) is very good to UV but cannot be moulded by normal means and is at best translucent milky white.
If it can be black or solid white, carbon black or titanium dioxide pigments offer considerable permanent UV protection to the polymer matrix, but not the surface.
Transparent durable stabilisation can now be obtained with nano sized white zinc additive, but at what price? It also only protects the matrix, not the surface.
Organic stabalisers protect the surface, but they are sacrificial.
Glass fibre reinforcment protects from crack propagation caused by microcracks that form on the surface when pigments are used for UV protection, so black, glass filled gives good almost permanent protection in polymers reasonably inherently stable like PET, PBT or even nylon.
Many boat deck fittings are carbon black, glass filled, UV and heat stabilised nylon or polyester, as are automotive roof racks and overhead electric power line fittings.
Regards
Pat
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RE: Moldable and durable polymer with excellent UV characteristics
RE: Moldable and durable polymer with excellent UV characteristics
BR
Piero
RE: Moldable and durable polymer with excellent UV characteristics
Whereas ABS is SAN with polybutadiene rubber particles in it, ASA is SAN with UV stable acrylic impact modifier particles.
See for example www.lurans.com
Chris DeArmitt
"Knowledge has no value except that which can be gained from its application toward some worthwhile end."
Think and Grow Rich - Napoleon Hill
RE: Moldable and durable polymer with excellent UV characteristics
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RE: Moldable and durable polymer with excellent UV characteristics
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