This review highlights recent advances in the synthesis of renewable polyols, used for making polyurethane foams, from biomass.

Bis(cyclo-carbonate) was successfully synthesized from D-sorbitol (Sorb-BisCC) through an environmentally friendly process with dimethyl carbonate (DMC) as a reactant. In agreement with green chemistry principles, solvent free reactions were catalyzed and took place at low temperature. The reaction yield was increased until 50%, with the use of 1.3.5-triazabicyclo[4.4.0]dec-5-ene as catalyst and a continuous DMC feed to limit the side-reactions or the loss of reactant by azeotropic flux with a reactional subsidiary product. The obtained Sorb-BisCC is a remarkable platform molecule which could compete with others polycyclic platform molecules (isosorbide). Sorb-BisCC can be e.g., used to synthesize different chemicals such as short and long polyols, or novel biobased non-isocyanate polyurethanes (NIPU). Two Sorb-BisCC molecules have been coupled to obtain novel cyclic diols with pendant side chains. Polyether polyols were also obtained by anionic ring opening polymerization. According to the synthesis conditions, these synthetized polyether polyols range from partially to highly cross-linked materials. Finally, NIPU were synthesized with short and biobased fatty diamines. These different modifications and synthesis highlight the versatility of the Sorb-BisCC and demonstrated its high potential as building block. Sorb-BisCC can be considered as a platform molecule to open the way to different original and biobased chemical architectures.

Novel rigid polyisocyanurate foams (PIR) produced from different polyesters polyols, such as a conventional fossil-based polyester polyol (as a reference) and a synthesized sorbitol-based polyester polyol, have been fully investigated. PIR foams were prepared by gradual substitution of the fossil-based polyester polyol by the biobased polyester polyol until a full substitution with adapted conditions. The foaming reactive process was monitored continuously to evaluate the impact of the temperature, the isocyanate trimerization, and the biobased polyester polyol on the foaming rate. The different foams were fully characterized and compared. Foams with 25 wt % of biobased polyester polyol show an impressive increase of 96% and 142% of their respective longitudinal and transversal Young’s modulus compared to the equivalent fossil-based reference. Mechanical properties of such foams are linked to their morphologies as they presented significant smaller cell sizes compared to the reference for a similar apparent density (30 kg/m3). The foams thermal conductivity, degradation, and flammability were also studied. Partially biobased foams show remarkable thermal conductivities until 22 mW/m K, whereas conventional values of equivalent fossil-based foams range from 23 to 30 mW/m K. Foams prepared with fully and potentially biobased polyol present the highest thermal resistance.

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Biobased and open cell polyurethane (PU) foams are produced from a synthesized sorbitol‐based polyester polyol. Different formulations are developed with various blowing agent systems (chemical vs physical blowing). Synthetized foams are fully characterized and compared. The cell morphology is carefully investigated by tomography and scanning electron microscopy. The chemical nature of the primary compounds, foaming kinetics, density, thermal behavior, and conductivity are fully studied, with also the main transition materials temperatures. It is shown that blowing agents especially impact the foaming kinetics. In the case of chemically blowing foams, higher foaming rate and temperatures are obtained. The mechanical behavior is particularly analyzed using quasi‐static compression tests, according two main axes compared to the rise direction. A direct relationship is observed between the formulation, foam structure, foam morphology, and corresponding mechanical properties. Results clearly highlight unexpected properties of biobased PU foams with unveil anisotropic mechanical properties.