I just remembered an interesting web app I found some time ago: [
www.matweb.com]
You can select a type of material (e.g. thermoplastic) and then specify up to 3 characteristics you need. It'll spit out a list of matching materials. By the looks of it, it has over 30000 thermoplastics in its database. I didn't see polycapralactone in there, though.
