The crystalline morphology of some FEP copolymers

prepared with different polymerization methods

with different hexafluoropropylene (F6) contents was studied by SALS technique.The results obtained show that the main factors which affect the crystalline morphology of the eopolymers are the content of F6

and the conditions for crystallization. The morphological structure of these copolymers could change from rod-like to spherulitical

as the F6 content changed from 2% to (14-19)% under usual air cooling condition.However

rod-like crystalline structure would form under very low rate of cooling (0.2℃/min). Some Hv patterns show that some fine structure also exists in addition to the two- and three-dimensional spherulites co-existiong in the specimens prepared under certain crystallization conditions.