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  1. clandestinho

    fungicide for 2K polyurethane coating in marine environment

    Hello everyone, I am looking for an efficient fungicide for a 2K polyurethane coating (polycarbonate based PUD and HDI). This coating will be used in a marine environment on a substrate that's semi-porous. The problem is mainly with black mold thriving extremely well on this hard but somewhat...
  2. clandestinho

    selecting a temperature sensor for air/solvent vapor

    Controlnovice, thanks for suggesting the Emmerson sensors, they look interesting and I would not have found them otherwise. Roydm, good point about the volocity, I had so far only seen the problems which are that the velocity will make a very thin element vibrate until it fails. But indeed...
  3. clandestinho

    selecting a temperature sensor for air/solvent vapor

    Xnuke, Yes, I was a little vague there, i'll try to be more specicif. response time I have found a fast response RTD with a time constant of 2 sec. @ 63.2% and with a 2" inserted length and in stainless steel for direct immersion. I think this would work but the 2 seconds are measured in...
  4. clandestinho

    selecting a temperature sensor for air/solvent vapor

    hello, I need to select a temperature sensor for an air flow containing solvent vapours. My criteria are - fast response. This is top priority - fair accuracy and repeatability. I would choose a 3-wire pt100 if it had a faster response - good chemical resistance. I would prefer an exposed...
  5. clandestinho

    Yellowing of Polyarylate

    Hi, I have an application where I would like to use polyarylate. It will be solvent cast into a thin film, 10 micron or there about. My only problem with this is that Polyarylate goes from clear, transparent to yellow when exposed to UV due to some rearrangement in the polymer chain. I...
  6. clandestinho

    UV protection in thin layer PU coating

    CompositePro, thanks for your reply. There's nothing in the coating from the supplier's side. The HALS (and anti microbial)are added by us and I also need to find my own solution for protection of the substrate. The resin supplier suggests to talk to the additive suppliers and they generally...
  7. clandestinho

    UV protection in thin layer PU coating

    Hi, I need to coat a solvent borne 2K polyurethane coating onto a flexible plastic (PET) surface. The coating thickness can't be more than 10-12 micron in order to stay flexible. The coating will have some light stabilisers (HALS) to protect the coating itself but I also have to add...
  8. clandestinho

    UV stabilizing of Polysulfone / polyethersulfone

    Hi Pat, toughness is top of the list, I forgot to mention this... Sorry. aramids have nice properties but would be too difficult to dissolve, I think. PC or perhaps polyester copolymers, as you say, could be possible alternatives, although a step down in some of the mechanical properties. I...
  9. clandestinho

    UV stabilizing of Polysulfone / polyethersulfone

    Thanks Chris, Thanks Pat, your help with this is most appreciated. Chris, thanks for suggesting the UV stabilized grade from RTP. I will see what they have to say and I will also look further into Tinuvin 234. It does look like a fairly modest improvement though and perhaps I just have to...
  10. clandestinho

    UV stabilizing of Polysulfone / polyethersulfone

    Hi all, can anyone suggest a way to UV stabilize polysulfone or polyethersulfone (Solvay´s Udel or Veradel) that will allow outdoor use? I have found some evidence that benzotriazole UV absorber in 1% concentration can do something but I am not sure that it will be enough. Anyone with...
  11. clandestinho

    PU coating to bond to polypropylene?

    Hi, I need to develop a PU coating resin that bonds to polypropylene. It needs to be a 2K solvent borne system and it's for a textile so it must be reasonably flexible. The isocyanate must be aliphatic. I am not looking for a soft PU dispersion for textile coating but rather a fairly tough...
  12. clandestinho

    Best nylon for fabrics under hot/wet environments

    There's a new high modulus PP fiber on the market called Innegra S. http://www.innegrity.com/index.php It has a kind of micro porous surface structure that I havent seen before in any fiber. They claim it provides a better grip for rigid composites and perhaps works with EPDM as well...
  13. clandestinho

    A method for refining bottle grade PEN ?

    Pat, Chris, thanks a lot, I now have something to work from. I will try both directions.
  14. clandestinho

    A method for refining bottle grade PEN ?

    Thanks Pat, interesting, and I agree that drawing, relaxing etc is just as important as polymer properties. Since you have this experience I would like to ask if there's a way to estimate yarn (or better, single filament) properties, primarily youngs modulus, from IV values of the PEN resin...
  15. clandestinho

    A method for refining bottle grade PEN ?

    Hi Chris, I much appreciate this advice and I will follow up on this and see what BASF thinks about my application. If this is doable it would be a much easier route to take. What I was trying to say was that PEN is used for a variety of purposes, from short life food containers to high...
  16. clandestinho

    A method for refining bottle grade PEN ?

    Hi Patprimmer, Hi Chris, let me provide some background. The resin is for filament fiber spinning. Normally high IV (>0.9 dL/g) PEN resin is used for this but Teijin which i believe is the only manufacturer of these grades has reserved their resins for their own films and fibers. Lower MW will...
  17. clandestinho

    A method for refining bottle grade PEN ?

    Patprimmer, thanks for the advice, I did some reading and it seems it can be done with PEN, only its a little more difficult to control due to the higher barrier of PEN which may cause volume expansion of the pellets. The process may also need an inert athmosphere to avoid oxidizing the surface...
  18. clandestinho

    A method for refining bottle grade PEN ?

    Hi all polymer people, this question is way outside my field so please bear with me if it's trivial or just impossible: I am trying to find out if there's a way to refine a bottle grade PEN (polyethylene naphthalate) resin into a higher I.V. grade? For example, is it possible to take a medium...
  19. clandestinho

    Painting on cast bronze

    Hi, does someone know a paint system that will work on cast bronze? I need to paint some machined parts for sea water pumps which will be used in a marine environment. I don't know what the particular alloy is but most likely the parts contain lead. any advice will be highly appreciated...
  20. clandestinho

    solvent for HDPE

    Unclesyd, thanks for taking time to advice on this. It was very interesting reading about the recycling method - which also confirms that xylene is a solvent for HDPE although at even higher temperatures. recyclability is one of several reasons that I am now looking at thermoplastics to...
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