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u/Aware-Lingonberry602

▲ 2 r/InjectionMolding

Overmolded Thermoplastics & Adhesion Expectations

Please help me settle a "debate" I have with some coworkers.

We produce a part from polyimide that we have overmolded with a polyphenylene ether/polystyrene blend. The polyimide part has a hole in the overmold area for mechanical attachment. This assembly has to be air-tight, so an extra liquid adhesive is applied and cured at the interface.

Some of my peers think the overmold should adhere to the polyimide, and I am trying to explain that is not how it works. My experience is theremoplastics require significant time at temperature to develop an adhesive bond to the substrate. At less than ten seconds, the overmolding process is not capable of producing a bond between the thermoplastic and the polyimide. If it did, the thermoplastic would also stick to the mold itself.

I'm struggling get this through to everyone. Is there a better way to explain this? Or, am I off base and need to be corrected?

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u/Aware-Lingonberry602 — 23 hours ago
▲ 2 r/arborists

Previous owner to our home planted a patten pear tree next to the deck. I realize this thing has a long way to go before it is mature. My better half doesn't like me killing shrubbery, and I think I'm beyond the point of moving given my narrow hill access. I did prune the roots 1.5 years ago.

My thing is, I don't want to sit on my deck and have a tree right next to it. Can I top and prune this thing so it doesn't become a monstrosity right next to my deck? The neighbor has a pear tree of a different species, so it does actually bear fruit. However, with a 10 month old baby, we can't really capitalize on it at this point due to priorities.

u/Aware-Lingonberry602 — 21 days ago