I haven't used polycarboxylate cement since my simulation lab days. I'm taking online courses on the fundamentals of dentistry and attended a materials science lecture where the technician mentioned something I'd never heard before. He said he still uses polycarboxylate cement because it not only chemically bonds to tooth structure (yes, no problem), but also bonds strongly to sandblasted metal, etched ceramics, and CHEMICALLY BONDS to PMMA and resins.
Is it true that it chemically bonds to PMMA and resin? I find that unlikely, and he didn't elaborate.

Perhaps a bond does form, but it's largely physical. For example, due to micro-surface adhesion after surface treatment. This means it's not a full-fledged chemical adhesion, as with metal or ceramics, but rather a combination of mechanical fixation and weak chemical interactions.

When using polyacrylet cement for lute restoration, it's recommended to consult the manufacturer or follow luteing recommendations in the content instructions. In some cases, resin cement may be better. If you are interested in using polycarboxylate it may be effective to rob metal and ceramic restorations, but caution is recommended for the specific properties of PMMA and materials.