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-Paz^2*

1 School of Chemical Engineering, University of Costa Rica, San Pedro Montes de Oca, San José, Costa Rica
2 National Nanotechnology Laboratory, National Center for High Technology, San José, Costa Rica

*Corresponding author:

Journal of Renewable Materials 2017, 5(3-4), 220-230. https://doi.org/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 high content of biobased macrotriol in the prepolymer formulation implies a softer final material than commercial polyester polyol foams due to the branched biobased molecules that do not allow enough packaging of the polymer matrix. Moreover, mechanical and thermal properties of the final PU foam are affected by the length, functionality and polarity of the biobased molecules used in the isocyanate prepolymer synthesis.

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Keywords

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