Properties of ABS vs % Water

[stanier]

Please advise if the long and short term mechanical properties of ABS are affected by its water content. I am specifically interested in an extrusion grade used for piping.

Geoffrey D Stone FIMechE C.Eng;FIEust CP Eng

http://www.waterhammer.bigblog.com.au

 

[dwightdixon]

Talk to your material suppliers. They have all this data.

 

[stanier]

That was my first port of call. Material suppliers do not necessarily have all the data.

Geoffrey D Stone FIMechE C.Eng;FIEust CP Eng

http://www.waterhammer.bigblog.com.au

 

[patprimmer]

The traditional good quality ones do, they just don't necessarily release it to the public.

Do you mean water content during moulding, or water absorbed after being moulded dry.

Suppliers like Lenxis (spelling?), GE, Dow or BASF will have data

Regards

eng-tips, by professional engineers for professional engineers
Please see FAQ731-376 for tips on how to make the best use of Eng-Tips Fora.

 

[stanier]

I am referring to both actually. My main interest is in the extruded pipe in ABS. It has been reported that the pipe when subjected to a heat reversion test passes however a few days later it fails. The material appears to absorb water from the atmosphere. Location is in the tropics with high temeprtures and relative humidity.

Geoffrey D Stone FIMechE C.Eng;FIEust CP Eng

http://www.waterhammer.bigblog.com.au

 

[patprimmer]

If you have equipment and are prepared to test, I can suggest some test methods I would try.

I have some old Bayer books in storage, I will try to find them and see what data they contain.

Regards

eng-tips, by professional engineers for professional engineers
Please see FAQ731-376 for tips on how to make the best use of Eng-Tips Fora.

 

[TechQA]

So far, i have not heard of any issues on % of water affecting ABS after processing be it extrusion or injection.Unless, ABS is undergoing many thermal history, water content will drastically affect the chemical structure of the material eg. poor impact strength.

 

[smallplaticstelford]

hi,
abs related concern,
I also had a problem where poorly moulded parts, months after moulding, starting taking in water, GAS marks on the product was the cause, as for some reason the parts acted like a sponge when gas marks had been produced (all ways by the night shift, setters joke lol) so simple vents and barrell, dryer temp check etc...if all ok then put and tiny system in place for Vent cleans every few hours problem gone, for now, then resource some good abs.

it could be this..
cheers
Linden