Roohalah Hajizadeh¹, Ali Khavanin^2,*, Mohammad Barmar³, Ahmad Jonidi Jafari⁴, Somayeh Farhang Dehghan⁵

Sound & Vibration, Vol.53, No.5, pp. 207-222, 2019, DOI:10.32604/sv.2019.06523

Abstract Polyurethane foam as the most well-known absorbent materials has a suitable absorption coefficient only within a limited frequency range. The aim of this study was to improve the sound absorption coefficient of flexible polyurethane (PU) foam within the range of various frequencies using clay nanoparticles, polyacrylonitrile nanofibers, and polyvinylidene fluoride nanofibers. The response surface method was used to determine the effect of addition of nanofi- bers of PAN and PVDF, addition of clay nanoparticles, absorbent thickness, and air gap on the sound absorption coefficient of flexible polyurethane foam (PU) across different frequency ranges. The absorption… More >

Aleksander Prociak^*, Elźbieta Malewska, Szymon Bąk

Journal of Renewable Materials, Vol.4, No.1, pp. 78-85, 2016, DOI:10.7569/JRM.2015.634129

Abstract In this article, the results of the foaming process analysis of fl exible polyurethane with different isocyanate indexes are presented. Two types of flexible polyurethane foams (FPURF) were obtained: (1) by using petrochemical components and a rapeseed-oil-based polyol (used in the amount of 20 wt%), (2) by using petrochemical components and cellulose as a natural fi ller in the amount of 3 php (per hundred parts of polyol). The characteristic parameters of the foaming process, such as the foam’s growth velocity, the core temperature and dielectric polarization, were measured using a Foamat device. Moreover, the More >

Sławomir Michałowski, Aleksander Prociak^*

Journal of Renewable Materials, Vol.3, No.1, pp. 14-18, 2015, DOI:10.7569/JRM.2014.634131

Abstract This article describes the effects of the modifi cation of polyurethane system with rapeseed oil-based polyol on the cell structure and physical-mechanical properties of conventional fl exible polyurethane foams. The foams were prepared by substituting a part of the petrochemical polyether-polyols mixture with the bio-polyol based on rapeseed oil. Selected physical-mechanical properties of these foams were examined and compared to the properties of reference foam. The properties such as apparent density, resilience, comfort factor and stress-strain characteristics were analyzed in compression tests. It was found that the modifi cation of polyurethane formulation with rapeseed oil-based More >