“I am having a hard time bonding polyethylene. Will texturing the surface of my substrate with microblasting improve the bond adhesion?”
Creating a texture on the surface will help with adhesion, however, the surfaces must be free of any dust or particles prior to bonding. An IPA wipe should be sufficient for cleaning. With some hard to bond plastics like polypropylene, silicones, HDPE, etc., this kind of abrasion may have minimal impact for bond strength.
“I am looking for an adhesive that can be used to bond tubes made of flurorocarbons (PVDF and FEP) to a titanium connector. This connection needs to withstand repeated autoclave sterilization at 134° celsius. Do you have any recommendations?”
Fluoropolymers such as PVDF, FEP, and PTFE (Teflon) are very difficult to adhere to. The only way to overcome this is by using a chemical etch solution. Two possible suppliers are www.actontech.com or www.fluorocarbon.co.uk. Both web sites also offer a variety of information regarding this topic.
The etching process removes a layer of fluorine atoms from the surface and allows oxygen and hydrogen from the atmosphere to attach, which enables adhesives to bond to it. The next challenge is the required resistance to repeated autoclave cycles. We recommend trying a two-part or heat-curable epoxy from Masterbond or Epoxy Technology.