Ap,

The manufacturers are 3M, ACC Silicones, Cedessa, Dow Corning, Electrolube and ResinTek. There are three basic compounds around, epoxy, polyurethane and silicone. Many of them are also loaded with fillers, typically to enhance thermal conductivity if any of your components dissipate significant power.

The silicone compounds have service temperature ratings of over 200C, so there is no way you can get them off with heat, but they only have a tensile strength of 1-6 MPa.

Epoxy resins typically have a maximum service temperature of around 130C, so many go soft or oxidise if heated to 150C. They are however much stronger, with a tensile strength of up to 80 MPa. Some like ResinTek E130-HT are also rated to 180C. In my experience, a big problem is that they are so strong that they can rip small components off their solder pads during the curing process as the epoxy moves.

Polyurethane compounds are the easiest to use, so I would suggest something like ResinTek U900 to start with as it wont damage delicate components.