Hey Boxer......experimented with a few adhesive materials when some
dingbat reversed into my previous [1980 something] Mitsubishi wagon & damaged the bumper & indicator bracket
1. Mitsubishi if not most vehicle manufacturers use an injection moulded high impact thermoplastic for such items
2. These are formed [moulded] from small pellets of plastic under elevated temperature but also under immense compressive forces [hydraulic presses] ...such hydraulic presses have design forces of many hundreds of tonnes
3. The material composition is designed to bend & deflect with a high yield strength prior to fracture, having said this the 'glueability' of such material is near ZERO
This is also why many solvents are stored or marked in plastic bottles
In the end I drilled & tapped a few M3 holes in the bumper bracket from the inside ...these were add mechanical strength to the joint prior to reassembly
I have used a number of
3M Scotch Weld products [gluing nitrogen valve seat disks in accumulators for components in missile launchers and gun mounts] and the products work perfectly for the as designed application
Plastic welding [a thermal process without flame] may work
....
Why not ask the Google WEB site for 3M .......[Minnesota-Mining-Manufacturing?] adhesive products for use with injection moulded high impact thermoplastics .....good luck
......Derek