Abstract
The Young's modulus of the 1 mil "Mylar" C polyester film was measured in a frequency range of 100 to 4000 c/s as a function of temperature, together with the study of the symptom of dependency on directions of the film. The frequency dependence of the Young's modulus has been found to be almost inappreciable. It has also been found that the values of the Young's modulus in dyne/cm^2 are 5. 2×10^<10> at 15℃ and 3. 3×10^<10> at 90℃ in the maximum direction, while 4. 2×10^<10> at 15℃ and 2. 8×10^<10> at 90℃ in the minimum direction. The variation of the Young's modulus with static tension was measured at 15℃ and 251 c/s which was found to be very small.
