PVC/ABS for exterior doors

[Soupcat]

Folks,
I would be interested on views as to the use of either uPVC or UV stabilised ABS for a glass frame strip on a glass panelled PVC door skin. I am currently working with my customer on designing the interior frame strip and we are debating as to which material to run with. The most popular colour for the application will be white. Could I reiterate that the frame strip is on the inside of the door and the target market area is subject to UK / Ireland weather conditions. Any experiences/views appreciated.

Regards

Kieran Fegan

http://www.moulddesigner.com

 

[plasticsguru]

I have found that ASA works very well for outdoor UV applications. One example that comes to mind is a sailboat body.

 

[Soupcat]

Plasticsguru,

ASA is another option I'm considering and indeed ABS/ASA blends. Thanks for your info

Kieran

http://www.moulddesigner.com

 

[patprimmer]

Just a question, as it's outside my experience, but do the additivies in so called uPVC leach out and stress crack ABS. I know this can occasionally happen with PC if the uPVC does in fact contain a little plasticiser "just to make it process nice" or at least that's what they claimed after it fell to bits.

I would think interior in UK is really minimal UV exposure.

I don't know about the low temperature properties that might be required Regards
pat

 

[Soupcat]

Kieran
Sorry, but I stayed away from that one, as I lacked knowledge in significant areas, ie the severity (or lack thereof) of exposure to UV in the UK, and only a limited knowledge of the UV properties of PVC.

ASA is much better than ABS and I expect a little better than PVC re delta factor, which is only a measure of discolouration. It is not a measure of loss of properties, and I think it is a bit naughty of ASA suppliers to infer it is. It all depends on the application, the environment and the additive package, as well as the resin.

My experiences with ASA in a full on outdoor envoronment, under cyclic load and chemical attack in Australia, is that even though it did not discolour much, it did stress crack, where glass filled, UV stabilised ABS survived, admitedly, much to my surprise.

My experience lays mainly with nylons, polyesters, acetal, polycarbonate, acrylic, and TPX
Regards
pat





Soupcat (Mechanical) Mar 5, 2003
Thanks Pat,

My application doesn't really have a mechanical function other than the fact that there are snap features holding it in place. PVC is probably the ideal material for me as resistance to discolouration is my primary concern and because of it's relatively low cost. But as you know most moulders tend to steer away from PVC and my job whilst having a relatively low shot weight is a large frame in a large tool hence a large press so the material will be residing in the barrel for a time before being injected. This is why I'm looking into alternatives and ASA seems to be the fore-runner at this stage. There doesn't seem to be a huge difference in price between ASA and UV stabilised ABS so ASA is the obvious choice between the two. As always thanks for your input.

Kieran

http://www.moulddesigner.com

 

[patprimmer]

Kerin

Sorry I answered in the wrong thread. It's midnight here, and I am a bit beat.

From what I imagine the part might measure and weigh, I certainly would not like to mould it in uPVC.

I would certainly take flow length to thickness ratios, as well as the thermal stability of the melt into consideration when chooseing the material.

Regards
pat