PHA pellet compositions are provided which are processible into blown and cast free-standing films. The Mw of the PHA in the pellets used to produce the films is at least 470,000, at least 435,000 if PHA thermal stabilizers of the invention are used. In order to achieve a stable, unsupported film having desirable elongational and tensile properties, the Mw of PHA in the film is greater than about 420,000.