Ether groups encapsulants

Polyethylene oxide glycols are converted from a waxlike state to firm solid by inclusion of fine silica which hydrogen bonds with the ether groups and cross-links the polymer. This effect is used in forming the walls of encapsulated materials (584). 

Epoxy resins containing bromine atoms are particularly useful in circuit boards, electrical laminates, and potting and encapsulation applications in which flame-retardant properties are desired. Brominated resins that contain bromine atoms ortho or para with respect to a glycidyl ether group or a hydroxyl group have been proved to be the cause of inferior thermal stability and wire bond failure [25]. 

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