Adherent Technologies Inc. (Albuquerque, N.M.) has developed a fiber finish system based on a patent-pending, heat-activated coupling agent that covalently bonds to carbon fiber and matrix resin to enhance the composite’s toughness and stiffness. Reportedly, the company’s tests of finished composite parts reveal such strong bonding into the basal plane of the carbon fiber that test to failure is not at the bond point. In test coupons, the finish system yielded the following improvements: In carbon fiber/vinyl ester, strength and stiffness increased by 50 to 100 percent, and toughness increased by 300 percent. In carbon fiber/epoxy, hot/wet performance and durability increased. In carbon fiber/bismaleimide, handling, durability, hot/wet performance and thermo-oxidative stability improved. In carbon fiber/polyimide, strength and stiffness went up by 50 to 100 percent and hot/wet performance improved. Adherent is seeking manufacturers with whom to develop licensing partnerships for the integration of the finish system.