ABSTRACT
Embedding and encapsulating of parts find wide use in industry because the processes offer many improvements in performance. Many resins are used to embed or encapsulate parts. These resins include epoxy, phenolic, polyester, urethane, acrylic, allylic, hydrocarbon, silicone, and sulfide types. There are a number of common factors to be considered when a resin is used for embedding or encapsulating a part. Shrinkage can occur during and after the embedding or encapsulating process. Fillers are widely used in embedding and encapsulating resin systems. There are several beneficial and often interrelated effects which result from the use of fillers in such resins. One of the major problems encountered in embedding and encapsulating processes that is a result of resin shrinkage is the internal stress on sensitive parts enclosed by the resin. An optical method was used to demonstrate the reduction of internal stresses achieved when an expanding monomer-modified acrylic resin system was used rather than an unmodified acrylic system.
