Application of noise reduction and heat insulation based on controlled-size polystyrene hollow microspheres

Core/shell polymer microspheres containing carboxyl group were prepared by emulsion polymerization, and then the hollow polymer microspheres (PHMs) were formed by infiltration and swelling after alkali solution post-treatment. Effects of emulsifier types and initial pH of alkali post-treatment on the particle size distribution and morphology of PHMs emulsion were investigated. Foamed animal skin material (FAS) was obtained by cross-linking and curing the skin collagen materials with PHMs. The results showed that the optimal initial pH was 9, and a stable PHMs emulsion with a maximum average particle size of 888.5 nm was obtained. The average particle size order of the PHMs emulsions obtained with different emulsifiers was: sodium stearate (1028.0 nm) > SDBS (823.6 nm) > cetyltrimethylammonium chloride (607.4 nm). The mechanical strength, porosity, and thermal stability of FAS were enhanced by PHMs dispersing and fixing, while its natural permeability and softness were retained. In addition, the whiteness and ultraviolet aging resistance of FAS were improved obviously. The thermal conductivity of FAS was reduced to 0.034 W/(K·m), which was in line with the standard of polystyrene foam board for building materials. In the range of 2000 ∼ 7000 Hz, the sound transmission loss of FAS reaches 25 ∼ 40 dB.