Not really PVA Alan, it won’t hold. It’s designed to lock into the surface and make a mechanical bond, but plastic like PVA isn’t porous enough to let it lock on. Model cement is best for polystyrene. It welds the surfaces together.
Do you mean expanded polystyrene al ,the white ball type stuff ? If so then pva wont really give much of a bond . The main problem is finding something thats sticky enough but not with any form of solvent as it just melts it. I think in the past ive stuck bits together with the water based ‘No nails’ type stuff , you can get it in poundland .
Good point Tony, never thought of that. You can stick expanded polystyrene with PVA, but you need to pin it or put weight on it while it dries overnight. Cocktail sticks work well for pinning.
I think PVA has no 'strength' in terms of larger scale bonding requirements for most plastics - however (if you roughen the mating faces as required) it can be useful for smaller, non-load bearing, surfaces such as placards or other material like 'foliage'. PS Also great for 'scabby skin' at Halloween! Useful for temporary placement of 'stuff' when planning layouts as well!
Steve
I’d go with generic glue, the clear type that’s usually sold in squeeze bottles for glueing paper, cardboard, plastic and sundry materials, and stinks pretty badly. It works fine on this kind of foam, and much better than PVA in my experience.
For some applications double sided tape works as well Alan. It depends upon the use you will make of the expanded polystyrene once it’s stuck together.