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  • Open Access

    ARTICLE

    Variation of Physical Properties of Rigid Polyurethane Foams Synthesized from Renewable Sources with Different Commercial Catalysts

    Daniel Brenes-Granados1, Jorge M. Cubero-Sesin1,2, Felipe Orozco Gutiérrez3, Jose Vega-Baudrit3, Rodolfo Gonzalez-Paz3*

    Journal of Renewable Materials, Vol.5, No.3-4, pp. 280-289, 2017, DOI:10.7569/JRM.2017.634118

    Abstract In this work, rigid polyurethane foams were synthesized from renewable sources using different catalysts to study their effect on the mechanical, thermal, chemical and surface properties of the foams. A commercial foam pattern was used as the reference pattern to compare the aforementioned properties. Concentrations of the commercial catalysts were optimized to obtain foams with similar mechanical properties to the commercial foam. Morphological characterization of the foams was performed by scanning electron microscopy (SEM). Fourier transform infrared (FTIR) spectroscopy was employed to investigate the characteristic functional groups. Thermal characterization was performed by means of differential More >

  • Open Access

    ARTICLE

    Rapeseed Oil as Feedstock for High Functionality Polyol Synthesis

    M. Kirpluks1*, D. Kalnbunde1, Z. Walterova2, U. Cabulis1

    Journal of Renewable Materials, Vol.5, No.3-4, pp. 258-270, 2017, DOI:10.7569/JRM.2017.634116

    Abstract In this study, polyols with high average functionality were synthesized from a renewable resource, rapeseed oil, as raw material for rigid PU foam production. A well-known method of rapeseed oil fatty acid double bond epoxidation was used to introduce oxirane rings into rapeseed oil structure. The temperature influence on epoxidation reaction conversion rate was studied by volumetric and FTIR spectra analysis. After epoxidation of rapeseed oil, an oxirane ring-opening reaction was carried out to obtain high functionality polyols. Diethylene glycol, a conventional oxirane ring-opening reagent, was compared to amine-based polyfunctional alcohols, diethanolamine and triethanolamine. The More >

  • Open Access

    ARTICLE

    Thermal-Mechanical Characterization of Polyurethane Rigid Foams: Effect of Modifying Bio-Polyol Content in Isocyanate Prepolymers

    Luis Daniel Mora-Murillo1, Felipe Orozco-Gutierrez2, José Vega-Baudrit2, Rodolfo Jesús González-Paz2*

    Journal of Renewable Materials, Vol.5, No.3-4, pp. 220-230, 2017, DOI:10.7569/JRM.2017.634112

    Abstract Nowadays, green polyurethane (PU) foams are mostly synthesized by replacing an amount of petrochemical polyol with biobased polyol. Here we report five different families of isocyanate prepolymer formulations that were prepared with biobased sources and the correlation between the structure of chains and the properties of the produced PU foam. Foam behavior in tension, torsion, compression, shape memory tests and physical properties were studied by dynamic mechanical thermal analysis (DMTA); interactions in the polymer chains were analyzed by Fourier transform infrared spectroscopy (FTIR); and thermal analysis was performed by thermogravimetry (TGA) and differential scanning calorimetry More >

  • Open Access

    ARTICLE

    Karanja Oil Polyol and Rigid Polyurethane Biofoams for Thermal Insulation

    M. Himabindu1, K. Kamalakar2, MSL Karuna2, Aruna Palanisamy1*

    Journal of Renewable Materials, Vol.5, No.2, pp. 124-131, 2017, DOI:10.7569/JRM.2016.634137

    Abstract Rigid polyurethane biofoams were prepared from karanja polyol which was derived by ring-opening reaction of epoxidized karanja oil. The polyol, which had a hydroxyl value of 186 mg KOH/g, was thoroughly characterized and the structure confirmed by spectral techniques. The foam formulations were developed to achieve shrinkage-free foams with water used as the blowing agent. The resulting foams were characterized for their mechanical properties like density, compression strength and flexural strength. The densities and mechanical properties, such as compression and flexural strength, varied with the amount of methylene diphenyl diisocyanate (MDI) for a fixed amount More >

  • Open Access

    ARTICLE

    New Closed- and Open-Cell, Aldehyde-Free Protein Foams

    María Cecilia Basso1*, Antonio Pizzi1,2

    Journal of Renewable Materials, Vol.5, No.1, pp. 48-53, 2017, DOI:10.7569/JRM.2016.634124

    Abstract New aldehyde-free and isocyanate-free biofoams have been obtained by reacting albumin chicken egg white and dimethyl carbonate (DMC). The optimized formulations yielded lightweight foams whose densities were evaluated as 0.016–0.16 g/cm3. Mechanical resistance was 0.023–0.34 MPa and residual pH nearly neutral. The new foams presented up to 57% of closed cells as measured by helium pycnometry and good thermal insulation. These new natural foams are environmentally friendly materials and show very promising properties. More >

  • Open Access

    ARTICLE

    Polyols Based on Poly(ethylene terephthalate) and Tall Oil: Perspectives for Synthesis and Production of Rigid Polyurethane Foams

    A. Ivdre1*, G.D. Soto2, U. Cabulis1

    Journal of Renewable Materials, Vol.4, No.4, pp. 285-293, 2016, DOI:10.7569/JRM.2016.634122

    Abstract This study presents the synthesis of novel polyols made from tall oil (TO) and poly(ethylene terephthalate) (PET) with different TO/PET molar ratios. Rigid polyurethane foams based on these synthesized polyols were obtained and characterized to evaluate polyols’ suitability for the development of light materials with insulating properties. The effect of TO/PET molar ratios on the physical, morphological and mechanical properties of the obtained foams, as well as their thermal insulation characteristics, were evaluated. Increasing amounts of PET in polyurethane foams resulted in higher compression strength and closed cell content, while water absorption was not affected. More >

  • Open Access

    ARTICLE

    Synthesis and Characterization of Polyurethane Rigid Foams from Soybean Oil-Based Polyol and Glycerol

    Facundo I. Altuna1, Borja Fernández-d’Arlas2, M. Angeles Corcuera2, Arantxa Eceiza2, Mirta I. Aranguren3, Pablo M. Stefani3*

    Journal of Renewable Materials, Vol.4, No.4, pp. 275-284, 2016, DOI:10.7569/JRM.2016.634120

    Abstract Mixtures of biomass-derived polyols were used to synthesize rigid polyurethane (PU) foams. A commercial polymerized methylene diphenyl diisocyanate (pMDI) was used as crosslinker, and distilled water served as foaming agent. The morphology and mechanical properties of foams with different glycerol and water contents were compared in order to evaluate the most suitable formulations. The rigid foams with higher water contents had larger and more anisotropic cells, explaining their lower density. Compressive moduli ranged from about 2.5 MPa to above 20 MPa and collapse stresses from 55 kPa to more than 1 MPa for densities between More >

  • Open Access

    ARTICLE

    Mechanical and Thermal Properties of High-Density Rigid Polyurethane Foams from Renewable Resources

    M. Kirpluks1*, U. Cabulis1, A. Ivdre1, M. Kuranska2, M. Zieleniewska3, M. Auguscik3

    Journal of Renewable Materials, Vol.4, No.1, pp. 86-100, 2016, DOI:10.7569/JRM.2015.634132

    Abstract The most common sustainable solution for polyurethane (PU) materials is their production using renewable resources. Polyols derived from biomass and recycled polymers are the most promising way to do that. This study compares five different sustainable polyols as a possible raw material for production of highdensity rigid PU foams for automotive application. The goal of our study was to show that biobased polyols are a suitable replacement for polyols derived from petrochemical products. The influence of the chemical structure of polyols on the PU polymer matrix and foam properties was investigated. Two sources of PU… More >

  • Open Access

    ARTICLE

    Influence of Isocyanate Index on Selected Properties of Flexible Polyurethane Foams Modified with Various Bio-Components

    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 >

  • Open Access

    ARTICLE

    Photodegradation of Polyurethane Foam Obtained from Renewable Resource–Pulp Production Byproducts

    A. Paberza*, L. Stiebra, U. Cabulis

    Journal of Renewable Materials, Vol.3, No.1, pp. 19-27, 2015, DOI:10.7569/JRM.2014.634138

    Abstract Rigid polyurethane foams were obtained from pulp production byproducts. Three different polyols were used—tall oil polyol, lignopolyol and commercially available polyol for comparison. The obtained rigid polyurethane foams underwent photodegradation at 60°C temperature and at 0.89 W/m2 intensity of UV light radiation up to 1000 h. Changes in chemical structure were observed by Fourier Transform Infrared Spectroscopy and Scanning Electron Microscopy was used to study changes in cell morphology. Spectrophotometery was used to determine yellowing of the foams. Results showed that the thickness of degraded layer for rigid polyurethane foams obtained from pulp production byproducts was More >

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