| Summary: | 碩士 === 輔仁大學 === 織品服裝學系 === 100 === In this research, by using the High Speed Auto Electroacoustic Test Instrument to apply electroacoustic tests on two types of film, microporous film and hydrophilic film. In microporous film type, 3 kinds of materials had been tested, including PTFE (Polytetrafluoroethylene), PU(Polyurethane) and PE (Polyethylene), while in hydrophilic film type, materials with TPU (Polyurethane) and PET(Polyester) had been tested, the purpose of this research is to find out correlations between these two types of breathable film and resonant frequency response by tests on different materials, thickness, water vapor permeability indexes, and resonance frequency values.
The results showed that, when the microporous film under different thickness, the frequency value of the peak point of resonant frequency response curve of the sound pressure level tends to have a relative large value. And when the microporous film with the same thickness under different water vapor permeability index, it showed that the frequency value of the peak point of resonant frequency response curve of the sound pressure level also tends to have a relative large value. Moreover the films with different materials, microporous and hydrophilic film respectively, it showed that resonant frequency response curves of the films with different materials could be distinguished obviously. And when hydrophilic films under different water vapor permeability index of Film, The frequency values of peak points of resonant frequency response curve of the sound pressure level did not show significant difference. We also found that the frequency response curve starting below the baseline, indicating that the material blocking part of the acoustic energy, resulting in energy loss. Finally, TPU film frequency response curve did not show peak pattern, and it means that there is no sound vibrations produced. While in PET film frequency response curve, it shows that there is an obvious peak pattern, and this phenomenon stands for when sound waves pass through, it will cause sever energy loss, and vibration effects.
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