Frequency- and temperature-dependent storage and loss moduli of microfibrous thin films of Parylene C

Elastic cyclic loading of ~110 µm-thick Parylene C thin films comprising parallel slanted microfibers was performed in the frequency range 5–200 Hz, to determine the dependences of their storage and loss moduli on the temperature and the frequency. The glass-transition temperature was identified as about 65 °C from the temperature-maximum of the loss modulus. A low-frequency peak (at 115–135 Hz) in the variation of the loss modulus is due to the resonance of an individual microfiber loaded by the remaining microfibers in the film.