S'Upermolecular Structures and crystallization behaviors of the gamma-radiation induced graft Copolymerization of styrene (St)-acrylic acid (AA) to polytetrafluoroethy-lene were investigated with electron-optical microscope and X-ray diffration.It was shown that the morphology of crystals obtained changes regularly with increasing graft dose.Four kinds of typical structure morphology (they belong to the linear structure.Graft network

ladder type network

cross-linked network) were observed from graft co-polymer layer. It is demonstrated that the grafted chain aligned perpendicular to the surface films. The results obtained from X-ray diffraction showed that the change of structure occurres; The crystallinity of macromolecular decreases;the size of crystal becomes smaller.