New flexibilized diallyl phthalate resins for encapsulating electronic display devices
This research investigated diallyl phthalate encapsulating resins as a replacement for the moisture sensitive epoxies now used in light emitting diode (LED) displays.Consideration of display resin requirements led us to select for study the diallyl phthalate (DAP) polymer thermosetting system, which had most of the performance properties desired, but was excessively brittle. Flexibilizing co-monomers were evaluated including both vinyl and allylic types. A promising co-polymer of DAP with lauryl methacrylate (80/20) was defined that had most of the physical and performance characteristics desired, plus attractive inherent light diffusing properties. Allylic co-monomers such as diallyl adipate and triallyl citrate also formed interesting co-polymers and ter-polymers with DAP.DAP/epoxy interpenetrating polymer networks were also explored and found to be most suitable for LED application.
Casting is a process in which a plastic part I formed by pouring a liquid resin into a cavit (mould), where the monomer is allowed to poly merize to a solid material. The polymerized solidmaterial is then removed from the mould. In encapsulation, the electrical or electronic componen is surrounded or enclosed by a material, and the entire assembly need not be completely surrounded Potting is similar to encapsulation; often the two terms are used interchangeably.