Enhancing sound insulation of glass interlayer films by introducing piezoelectric fibers

Traditional polyvinyl butyral (PVB)-laminated glass could not satisfy the rising requirements of sound insulation due to the mass law, especially in the low-frequency region. In this study, a new strategy that uses piezoelectric fibers to improve the sound insulation of materials is first proposed. Polyvinylidene fluoride (PVDF)/multi-walled carbon nanotube (MWCNT) membranes were prepared by electrospinning. Thereafter, laminated glass with glass/PVB/PVDF/PVB/glass structure was successfully constructed by the hot pressing process. 30 pC/N of the maximum piezoelectric coefficient (d(33)) and 2 V of the maximum output voltage for the PVDF/MWCNT membrane were achieved. The PVB/PVDF composite glass interlayer film could break the conventional mass law with a transmission loss of over 15 dB in the low-frequency region (200-500 Hz). On average, 48% passing through sound energy was reduced than that for the pure PVB film, which indicated the effective block out of human noise. The excellent transmittance and impact resistance of the composite laminated glass were also confirmed from the ultraviolet spectrum and falling ball impact test, respectively. It is of great significance to the research and development of sound insulation materials.