Adhesive will not wet a surface that is much lower in energy than the mix. This sheet uses about 38–40 dynes/cm as a practical glueability window. Values below are typical published surface tensions, not a spec for every lot. Treat, prime, or pick a different chemistry when the substrate sits well under that window.
What's in this guide
The sheet also lists polyamide, epoxy, fluorocarbon copolymer elastomer, and polyacetal as materials tested below 36 dynes/cm — treat or prime those before you expect a water-based or many hot-melt bonds.
Related: How to bond plastics, low-surface-energy substrates, corona, ozone, or flame, primer for extrusion coating.