The most common problems with epoxy and urethane applications

Bubbles are either caused by moisture in the mix or air trapped in the material because the mix was not de-aired.

Symptoms

The Effects of Filler Settling

Many formulated compounds contain fillers to impart desired properties. The fillers are incorporated (mixed) into the resin and/or hardener or both at the time the products are manufactured. Although formulators take great care in selecting fillers and use various additives to keep them in suspension, there will be some settling occurring under certain conditions.

 Result of reaction with moisture in the air, Resin may have crystallized problems.

Epoxy and Polyurethane compounds are widely used to encapsulate electronic circuits. Depending on the type of components contained in the circuit and the performance requirements for the finished components, it is critical to select the appropriate formulation. The type of fillers, pigments, thermal conductivity, the electrical properties, the amount of shrinkage during cure and adhesion to containers can all effect the output of an encapsulated circuit.

It is worthwhile to conduct some general tests before getting involved with detailed trouble shooting. The majority of the difficulties encountered are related to mix ratio, defective or unclean equipment or not following supplier instructions.

The most common problems with epoxy and urethane applications.

Epoxy and urethane compounds are best processed through automated dispense equipment, especially in high volume production situations. From time to time, problems are encountered due to various causes, resulting in the improper cure of the epoxy or urethane mix