Plastic for UVC Rays

[RacinFrk]

Hi all,

New to this forum which I ran across while researching plastics for a product that my company manufactures. This is a cylinder that produces low levels of ozone using a UV light.

I am looking for a plastic that can handle the following:

1. UV output of 254nm (about 85%) and 185nm (about 15%).
2. Ozone resistant.

Through my research, I was originally leaning towards UV Stabilized ABS. Which after reading through this forum I came to the conclusion the the rubber in ABS will cause the plastic to become brittle and crack. In one of the threads (

http://www.eng-tips.com/viewthread.cfm?qid=281459)

it was recommended to use ASA (Luran S 778T). After doing some research and talking to BASF I was told that ASA has not been tested for our UV output. So, my question is does anybody here have experience with ASA for this type of application? Can you recommend me a material that will work? I know Kynar will work, but it is cost prohibitive.

Thank you in advance.

 

[Demon3]

Hello, it was probably me that recommended the ASA. I don't know who you spoke to at BASF / Styrolution but they have sold ASA for over 25 years specifically because it's great against UV light i.e. sunlight. It's used on house sidings because it's more resistant that PVC and it's used in external car parts like radiator grills. ASA is one good choice. PMMA is another one that's used outdoors in sunlight. There are books on this topic and you can find quite a lot online but look to what has been used for decades outdoors.

Because the conditions you specified are unusual you will have to do testing on the material you choose. Try buying some ozone generators from well respected companies and then have the plastic analyzed to see what the plastic is and what stabilizers they added to protect it.

Dr. Chris DeArmitt

Plastics consultant to the Fortune 500:

http://www.phantomplastics.com

Webinars on plastics, fillers & impact modification:

http://www.plastictraining.com

 

[Pud]

Are you wanting UV resistance to exposure or transmission through it?

www.tynevalleyplastics.co.uk

It's ok to soar like an eagle, but weasels don't get sucked into jet engines.

 

[RacinFrk]

I am looking for resistance to exposure.

We used to have this molded out of Black CPVC. However, we have been told that Black CPVC is no longer available and CPVC in general is being phased out.

 

[Pud]

Nylon (all types) with a UV additive is pretty good. Black pigment using activated carbon instead of lamp black gives additional protection.


www.tynevalleyplastics.co.uk

It's ok to soar like an eagle, but weasels don't get sucked into jet engines.

 

[Pud]

Oh, and as Chris mentioned, ASA is also a good choice - no tool change required as shrinkage around the same as CPVC.

www.tynevalleyplastics.co.uk

It's ok to soar like an eagle, but weasels don't get sucked into jet engines.