Soundproofing performance of flexible polyurethane foams as a fractal object
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Noise pollution is one of the most severe environmental concerns due to its damaging effects on human health. This study aimed to evaluate the relationship between the acoustic damping behavior and fractal dimension (Df) of flexible polyurethane foams (FPUFs) manufactured by different synthesized linear saturated aliphatic polyesters (LSAP) resins, methylene diphenyl diisocyanate (MDI), etc. (isocyanate index = 110 & water content = 5%). Cellular and soundproofing properties of FPUFs were evaluated by an optical microscope and impedance tube device. Df was calculated by the box-counting method after binarization and image processing of FPUF images. Results indicate that by increasing Df from 1.5415 to 1.8554, the total sound absorption performance (S) of FPUFs improves by 43.07% and the maximum sound absorption coefficient reaches 0.98. The relation between S and Df was obtained as follows: Log(S) = 0.4583 Df + 2.6659, r2 = 0.9298. Generally, decreasing the cell size and increasing the cell size distribution and open-cell content, increase Df and irregularity of FPUFs. The results reveal that FPUFs with an optimum condition of cell size of 180–200 μm, open-cell content of 30%, and density of 110 (Kg.m−3) have the highest Df and can be a promising candidate as sound insulating materials.
KeywordsFractal dimension Soundproofing Flexible polyurethane foam Linear saturated aliphatic polyester resins Box-counting method
The authors would like to acknowledge the Color & Polymer Research Center (CPRC) for the financial and their kind support.
All authors contributed to the study conception and design. Material preparation, data collection, and analysis were performed by Sahar Abdollahi Baghban. Also, the draft of the manuscript was written by Sahar Abdollahi Baghban under the supervision of Manouchehr Khorasani and Giti Mir Mohammad Sadeghi.
Compliance with ethical standards
Conflict of interest
The authors declare that they have no conflict of interest.
- 14.Mahmoud AA, Ader Nasr EA, Hamed Maamoun AA (2017) The influence of polyurethane foam on the insulation characteristics of mortar pastes. J Miner Mater Charact Eng 5:49–61Google Scholar
- 37.Gayathri R, Vasanthakumari R, Padmanabhan C (2013) Sound absorption, thermal and mechanical behavior of polyurethane foam modified with nano silica, nano-clay and crumb rubber fillers. Int J Sci Eng Res 4:301–308Google Scholar