the best adhesive for a PVC material — and hence a vinyl fence — is an epoxy adhesive. Epoxy adhesives often come in a two-part arrangement, typically a resin and a hardener. Loctite has a ...

Perfect Repair: Metal glue is a high strength epoxy adhesive used as an alternative to torch welding, providing strong and durable repairs to metal and several other surfaces, forming a strong and ...

This included everything from epoxy to wood glue and various adhesives for plastics TL;DR: Some superglues seem to weaken PETG, and a construction polyurethane glue is the absolute winner.