Chemical modification of carbon fiber surfaces

Surface properties of a high modulus unsized carbon fiber modified by aqueous ammonia were studied. Basic groups were detected by potentiometric titration in addition to the pristine acid groups in untreated fiber. Surface composition of fiber modified with maleic anhydride or tetracyanoethylene was determined by XPS analysis. The modified fiber interaction with epoxide resin was studied by the Single Fiber Composite test. Ammonia treated fiber showed an improvement of the fiber/matrix stress transfer. (C) 2002 Elsevier Science Ltd. All rights reserved.