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Suggestions for metallic finish polypropylene

Hi, as you are probably aware, parts made from polyproplyene with a metallic finish are notoriously bad for showing flow lines. Can anyone suggest a way of finishing a PP part, that achieves a metallic finish, without increasing the price? Thanks!

Sarah Andrews
Designer - London, UK
July 21, 2008

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Is this a final year project or something!

Trevor Crichton
R&D practical scientist
Chesham, Bucks, UK
July 28, 2008

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July 29, 2008

One of the things that makes polypropylene good is that it is relatively inert. This means that it is hard to do anything with it. Metal or paint are both hard to get to have but the most minimal adhesion. You might kill the gloss with a light blast, probably with tiny glass beads at a relatively low pressure. This will tend to hide the flow lines, but it will get dirty quicker and some might think that it is ugly.

Now, at no increase in cost. Absolutely not possible. If you just wash it and dry it , you have used physical resources and time. Both cost money.

Have you looked into an appropriate dye. It might help and it might not. Not all poly absorbs moisture the same.

James Watts
- Navarre, Florida