Although it is quite common to use Teflon Tape for threading the joins between different segments is is only suitable as a emergency measure. Teflon tape threading is not elastic so there is no guarantee for the tightness of the join.
When making reeds — especially plastic reeds — teflon tape can be used for sealing double reeds. Instead your average seran wrap/cling film is just as suitable and much more environment friendly.
In case you were wondering why fried eggs do not stick to a teflon-covered frying pan, the internet knows the answer.