Study on the direction dependence of Young's modulus of drawing polypropylene film.

The Young's modulus of drawing polypropylene film appear strongly direction dependence. Expressions for the direction dependence of the Young's modulus in the polypropylene film have been drived and have been applied to the drawing polypropylene film. The followiing results were obtained; 1. The dynamic Young's modulus and Young's modulus of the monoaxial drawing polypropylene film show strongly direction dependence. 2. The dyanamic Young's modulus and Young's modulus of the simultaneous biaxial drawing polypropylene film appear slightly direction dependence. 3. The expression for the direction dependence of the Young's modulus of the drawing polypropylene film may be expressed as Eθ=E11cos2θ+E12sinθcosθ+E22sin2θ where Eθ is the Young's modulus of θ direction to the drawind direction, E11 is the Young's modulus of the drawing direction, E22 is the Young's modulus of the perpendicular direction to the drawing direction and E12 is the mixed Young's modulus. The agreement between the measured and the computed Young's modulus is very good