Antonio Pizzi*

Journal of Renewable Materials, Vol.7, No.5, pp. 477-492, 2019, DOI:10.32604/jrm.2019.06511

Abstract This review details the development of tannin-based biofoams for fire resistance and acoustic insulation and details the different varieties of these foams that have been developed, from tannin-furanic self-blowing foams to tannin-furanic polyurethanes and finally non-isocyanate tannin-based-carbohydrates polyurethanes (NIPU). More >

Xuedong Xi^1,2, A. Pizzi^1,*, C. Gerardin³, Guanben Du²

Journal of Renewable Materials, Vol.7, No.3, pp. 301-312, 2019, DOI:10.32604/jrm.2019.04174

Abstract Glucose-based non-isocyanate polyurethanes (NIPU) were prepared by reaction of glucose with dimethyl carbonate and hexamethylene diamine. These were used to prepare partially biobased polyurethane foams by reaction with NaHCO3 as a blowing agent and addition of a silane coupling agent having different functions such as coreactant and adjuvant to obtain more uniform and smaller cells. The foams were foamed and hardened by applying heat. The foams presented very limited fire resistance indicating that as for synthetic polyurethane foams the eventual use of a fire retardant appears to be necessary. The 2 hours water absorption was used to indicate if close… More >

S. Gaidukovs^1,2,*, G. Gaidukova², A. Ivdre^1,3, U. Cabulis³

Journal of Renewable Materials, Vol.6, No.7, pp. 755-763, 2018, DOI:10.7569/JRM.2018.634112

Abstract This article deals with the study of the viscoelastic and thermal properties of polyurethane (PU) rigid foams from biobased and recycled components. Rapeseed oil (RO) and recycled poly(ethylene terephthalate) (PET) were used to synthesize PU polyols. Addition of adipic acid (ADA) to polyol resulted in improved thermal and viscoelastic properties of foam materials. ADA content was varied from 1 to 6 wt%. Results of the dynamic mechanical spectra indicate an increase of the storage modulus E′ and the loss modulus E″ in the whole temperature range for specimens with higher loading of ADA. In addition, damping factor shifted to higher… More >

Daniel Brenes-Granados¹, Jorge M. Cubero-Sesin^1,2, Felipe Orozco Gutiérrez³, Jose Vega-Baudrit³, Rodolfo Gonzalez-Paz^3*

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 scanning calorimetry (DSC) and thermogravimetric… More >

M. Kirpluks^1*, 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 introduction of tertiary amine groups… More >

Luis Daniel Mora-Murillo¹, Felipe Orozco-Gutierrez², José Vega-Baudrit², Rodolfo Jesús González-Paz^2*

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 (DSC). The results showed that… More >

M. Himabindu¹, K. Kamalakar², MSL Karuna², Aruna Palanisamy^1*

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 of polyol and other additives… More >

María Cecilia Basso^1*, Antonio Pizzi^1,2

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 >

A. Ivdre^1*, 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. Results indicated that certain TO/PET… More >

Facundo I. Altuna¹, Borja Fernández-d’Arlas², M. Angeles Corcuera², Arantxa Eceiza², Mirta I. Aranguren³, Pablo M. Stefani^3*

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 54 and 143 kg/m3. Densification… More >