Wednesday, March 25, 2009

Solvent Bonding Polycarbonate to Polycarbonate - Update

It didn't work well. Unfortunately, it seems the bond created was very porous (see image below). After curing in a fume hood for 18 hours, the surface was still a bit tacky (after pulling the two pieces apart). The bond surface was abot 1/4" square and held roughly 20 lbf before seperating. It may have been stronger had it cured all the way, hard to know for sure. I only tried a few samples, so perhaps there are process tweaks I could make that would improve the efficacy of the cyclohexanone bond, but at this point it seems a less than ideal solvent for bonding polycarbonate to itself.


Sunday, March 15, 2009

Solvent Bonding Polycarbonate to Polycarbonate

I encountered the need to solvent bond Polycarbonate to itself for one of the projects we're currently working on. After speaking with several vendors and reading various snippets online, I discovered that Methylene Chloride is the solvent of choice for bonding polycarbonate. Great, right? Except not so great. This is why: the method of sterilization we've chosen for our product is EtO (and we can't change it for technical reasons), and apparently EtO sterilization does not react well to anything with chlorine in it. So, the chloride part of methylene chloride presents a challenge. After further digging, a technician at Masterbond recommended a chemical called Cyclohexanone (which, I confirmed, has no chlorine in it). I've got some on order and plan on doing a test this week. I'll fill you in on the results when I have them.

Moral of the story - methylene chloride is the solvent of choice for bonding polycarbonate to itself; however, if you'll be EtO sterilizing your parts, using methylene chloride won't work and you should consider an alternative, possibly cyclohexanone.

Monday, March 9, 2009

Have A Medical Devices Idea? Recovery Act provides Funding!

If you have a concept for a medical device and need seed stage funding this could be a unique opportunity for you. The NIH recently announced that it will be awarding $200M in additional research funding due to the Recover Act (see RFA for specifics). Small business are eligible for this funding. Contact PADT Medical if you are interested in learning how we can partner with you and advantage of this unique opportunity.