The production and properties of poly(vinylidene fluoride) rods oriented by drawing through a conical die

Highly oriented poly(vinylidene fluoride) rods have been produced by drawing isotropic polymer through a conical die. A range of oriented products was obtained, depending on the drawing temperature and the deformation ratio achieved. At low draw temperatures the draw ratio and final modulus are comparatively low, but a high Form I crystal content is obtained. At high draw temperatures the Form I content varies greatly with draw ratio, reaching high values at large draw ratios, where the highest‐modulus samples were obtained.