design and fabrication of polyurethane composite foams reinforcement with rock wool fiber; effect of the non-acoustical parameters on sound absorption coefficient

The present study aimed to focus on improving acoustic and mechanical characteristics by embedding the polyurethane foam (PUF) with the rock wool fibers (RWF) of diverse values (۰-۳wt%) that were synthesized using the polymerization process. In addition, the association between non-acoustical parameters and sound absorption characteristics of the porous polyurethane foams was investigated. Moreover, indicators of effective non-acoustic parameters, including air-flow resistance (AFR), porosity, volumetric density, and microstructure, were determined. The results showed sound absorption properties were highly enhanced when polyurethane composite foam (PUF/RWF) (i.e. ۱, ۲, and ۳wt%) were used, as compared to the pristine PUF. Furthermore, the sound absorption coefficient (SAC) of PUF composite was highly enhanced in the frequency range of ۴۰۰ to ۱۶۰۰ Hz when the foam was combined with an RWF amount of ۲wt%. Besides, the density and AFR increased with the addition of different contents of RWF. Open porosity composite foams strongly depended on AFR and volumetric density (i.e. a negative association with RWF content). The use of the excessive amount of the RWF (RWF > ۲wt%) caused intramolecular agglomeration, which resulted in reduced sound absorption efficiency. Finally, multiple regression analysis was used to investigate the association between SAC and non-acoustic parameters, including AFR, porosity, volumetric density, and RWF amount, which revealed a well proportion between experimental data and statistical analysis.

کلیدواژه ها:

sound absorption coefficient ، rock wool fiber-based material ، open-cell foam ، polyurethane foam ، non-acoustic parameters