US Patent 11180632 Unsaturated polyester resin system for cured in-place piping

A process to use an unsaturated polyester resin system comprising preparing a curable cumene-quat curing system. The cumene-quat curing system can comprise an unsaturated polyester resin, a peroxide initiator, a quaternary ammonium salt component, a 2,4-pentanedione component, and an inhibitor component. The peroxide initiator can comprise a cumene hydroperoxide component. The process can further comprise applying the curable cumene-quat curing system in a cured-in-place pipe rehabilitation process.