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View Full Version : Adding wood shavings to transparent polymer ?



Chops
10th May 2017, 05:35 AM
Hello guys, we're a California startup going through the sampling process and currently having some troubles with our manufacturer. We are trying to mix tiny wood shavings with a transparent polymer so you can see the flakes suspended inside. However, we have been told that a lot of factories are worried about ruining their machines, the wood might not be able to handle the heat, etc. So, our current factory tried a cold process that resulted in a ton of air bubbles(see image below). Can anyone please please please send some recommendations of a cost efficient ways/processes to possibly get better results? Any help would be greatly appreciated. Thanks so much.

Paolo
10th May 2017, 11:38 AM
Hellow Chops,

I've seen extrusion process with wood shavings in my university and I believe the investigation went on the TV news here. I know they were investigating the injecion molding process/mechanical properties with wood-plastic composites too. If you want I can send you the paper, just give me your email.
BR.
Paolo

rickbatey
11th May 2017, 12:58 AM
I think the part is too think to allow you to pack out air bubbles but they may be formed due to too little packing pressure/sink bubbles. The only way to know is to heat plastic and if they pop, trapped air. If not the molten resin fills the hole.
To mold this you need a weight blender setup for such particles and a wear hardened screw and barrel. I also think tge compression ratio will need to be lower than a standard IM to protect the wood chips.
BTW what is the resin? The resin may not be properly dried or processed.
Rick

Jason S.
12th May 2017, 02:20 PM
I wonder if the air bubbles could be from the wood? I would imagine if it wasn't dried along with the resin it could hold a ton of moisture in it. Are you drying the wood chips also?

Chops
14th May 2017, 09:45 PM
Thanks for the help guys, we're gonna relay this advice to our factory to see what can be done. What do you guys think about vacuum casting??