Plastics suitable for -40C applications

[Jboezi]

I'm looking for recommendations on plastics suitable for function at a temperature range down to -40C. This will essentially be a block, its sole functional requirement will be a compressive load, so I need something that doesn't become brittle at -40C. The resin must be injection moldable. I'm currently investigating glass filled nylon. What are good cold temperature resins?

Thank you in advance.

 

[unclesyd]

I would contact TriStar with your specific requirements. ZZI would look at Rulons, especially the 945 or their Ultracomp material. I think you will what you want from TriStar.

http://www.tstar.com/default.asp?LINKNAME=RULON&playMovie=77

http://www.tstar.com/materialsearch/default.aspx

 

[Demon3]

ABS as the rubber in it is polybutadiene which has a Tg of -80 so it's still functional at -40C.

Chris DeArmitt PhD FRSC CChem

http://www.phantomplastics.com

Consultant to the plastics industry

 

[Pud]

For pure compressive stress, most will do. It's the impact strength (iirc) for polymers that is a bit of a disaster at low temps.

LLDPE is good for -70°C, but not much else.

H

http://www.tynevalleyplastics.co.uk

 

[Demon3]

What Pud said.

Chris DeArmitt PhD FRSC CChem

http://www.phantomplastics.com

Consultant to the plastics industry

 

[patprimmer]

LLDPE is cheap and good at -40C.

Nylons are not good that cold but impact modifiers help. I would need to check the state of the art with nylons down that low. One problem is the cold air drys them out and nylon impact strength is very dependant on water absorption.

Polyester block co-polymers like Hytrel and Arnitel are very good at -40C but are quite expensive.

Regards
Pat
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[Jboezi]

Thanks for the responses. I typically use Matweb for my material research. Is there a better source that specifically lists cold weather resins, for my comparisons? I've noticed that a typical characteristic listed is max temp, indicating the higher limit. I've been using Izod low temp (-40) to compare resins at low temp.

I've looked at rulon, xenoy 6370, and I'll check out LLDPE next. Anyone actually spec a resin in a product for these application temps? Airplanes come to mind (ignoring thermosets).

 

[patprimmer]

Hytrel is specified in snow ski fittings.

Regards
Pat
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[Demon3]

If you expect the part to be subject to impact (which I assumed above) then I stand by ABS as a good choice.

The CAMPUS database may be better for you than matweb although I do use MATWEB too.

Plenty of plastics are used at low temperature like Pat said in ski equipment and much more.

Chris DeArmitt PhD FRSC CChem

http://www.phantomplastics.com

Consultant to the plastics industry

 

[dgowans]

Lexan EXL reportedly offers excellent performance at low temperatures.

 

[Jboezi]

Zytel ST801 is a strong candidate, or it's BASF equivalent (maybe Ultramid A3Z HP).

Further discussion with some tech reps has led me to be more comfortable using unfilled nylon 6/6 at these temperatures. The rep cited some GM applications as well as military.

 

[Pud]

We make military parts from ST801 and an EMS Chemie equivalent AZ3:

http://ems.materialdatacenter.com/eg/en/ds/Grilon+AZ+3+

H

http://www.tynevalleyplastics.co.uk

 

[HDS]

PP and PE can be used at low temps. Alot of it is part design avoiding sharp corners ect.

Many automotive parts have to work at -40C.

 

[patprimmer]

PP homopolymer has an embrittlement temperature of about -10 deg C. PP used externally on cars are co-polymers.

Regards
Pat
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