Adhesives can be classified in several ways, including their material origin (e.g., natural or synthetic) and their type of cure (e.g., physical curing such as drying or chemical curing).

Adhesive and coating systems that use ultraviolet (UV) or visible light to begin the curing are intrinsically very attractive systems to the manufacturing engineer, allowing assembly of components and then “curing on command” by exposing to the radiation.

Acrylics such as tough acrylics and anaerobics are routinely used at 150˚C in situations like automotive under-the-hood applications.

Over a long career, I have worked with several adhesive and sealant technologies and have tried many of them at home.

In the plumbing industry, solvent-based PVC cements are used for bonding PVC plastics. However, if you need a solvent-free system, cyanoacrylates and reactive acrylics have been widely used on rigid PVC.

I started my career as a chemist with Loctite Corp., and we used to manufacture our own monomers.

This is a good question for two reasons: first, adhesives and sealants often have to fill large irregular gaps and expansion on curing enables them to achieve this; and second, the products usually shrink on curing.

I suspect that the concentration of your products in the water is very low, but the answer is almost certainly no!

We have some pinhole leaks in an old fire sprinkler system in a large apartment block. Is there an adhesive that will seal those leaks?

Polytetrafluoroethylene (PTFE) is low-surface-energy plastic that is very difficult to bond. PTFE exclusively comprises fluorine and carbon atoms with no polar atoms such as oxygen or nitrogen.