A polyimide is typically a family of thermoplastic (and some thermoset) resins characterized by repeating imide linkages.
Most polyimides are thermoplastics, but can be end-capped with functional groups to make them thermosets
This charge transfer complex holds the chains together very tightly, limiting molecular movement. This is why polyimides are so strong.
- Key properties
: good reliability performance for film adhesives
: excellent thermal stability
: high Tg
: good adhesion to metals
: fast attach time for film adhesives - Typical uses
: thermoplastic resins are used for film applications that require <1 second attach times
: die attach for memory chips
: applications requiring high temperature resistance - Limitations
: high moisture absorption
: high cure/process temperatures required
: solvents used in paste products and residual solvents in film products may cause voiding in the bond line if not cured properly