the problem you will have is that as the prop is spinning it will look weird and you wont get a curved prop you will get a straight line because of how the prop is blurred through the frame. What I would do (and have done on projects before) is to duplicate the propa few times and offset it's rotation so that each one starts a little bit behind the next. That way you will get proper motion blur and it will be curved rather than straight.

A
Technical Director - Framestore
Currently working on: Your Highness
IMDB