Enhanced Soundproof Performance of Construction Coatings Using Polyvinyl Acetate Resin and Calcium Sulfate Whiskers: Fid-Bau Portal

Enhanced Soundproof Performance of Construction Coatings Using Polyvinyl Acetate Resin and Calcium Sulfate Whiskers

Yang, Hsi-Chi / Tasi, Tsung-Pin

This study reports an enhanced soundproof performance of polyvinyl acetate (PVA)-based coating by adding high-aspect-ratio calcium sulfate whiskers. One efficient microwave-assisted (MA) method is adopted to synthesize ${CaSO}_{4}$ whiskers with a high aspect ratio of 40–80. The two-step MA method is capable of forming highly crystalline ${CaSO}_{4} \cdot 2 H_{2} O$ crystals at 85°C, demonstrated by X-ray diffraction analysis. This work uses an anechoic termination method to analyze the sound transmission loss (TL) of PVA-based coatings. The TL of ${CaSO}_{4} / PVA$ composite coating shows an increased trend with the amount of ${CaSO}_{4}$ whiskers within the frequency region of 400–3,600 Hz. The improved TL can be attributed to the fact that an air pocket is contained in the ${CaSO}_{4}$ stacking layer, imparting the reflection and refraction during the sound wave transmission in the composite coating. The energy of incident sound waves is weakened by consecutive reflection, scattering, refraction, and diffraction of sound waves in the ${CaSO}_{4} / PVA$ composite coating. Since the ${CaSO}_{4}$ whiskers are synthesized from industrial wastewater by the MA method, the ${CaSO}_{4} / PVA$ composite coating can serve as eco-environmental decoration materials due to its excellent soundproof performance.