The petrochemical chain extenders and polyols can be replaced by bio-derived compounds such as 1,3-propanediol (PDO), 1,4-butanediol (BDO), and bio-based poly(trimethylene glycol), which are produced by environmentally friendly biotechnological syntheses. Thermoplastic polyurethanes (TPUs) are important groups of polyurethanes, obtained by the reaction of polyols, diisocyanates, and chain extenders - usually glycols (Król, 2007). This caused a search for renewable monomers that can replace the usual synthetic monomers, for materials synthesis, without worsening the properties of the final products (de Oliveira et al., 2019 Lligadas et al., 2013). Moreover, they allow the reduction of energy consumption during production, the reduction of greenhouse gases’ emissions (including decreased CO 2 emissions), and the biodegradability improvement (Mulhaupt, 2013). As a result, there is an improvement in economic stability in the countries without access to fossil fuels (Parcheta and Datta, 2017), since bio-based monomers production provides a decrease in the synthesis cost with an increasing amount of production. Additionally, the substitution of the petrochemical components allows for economic volatility reduction by the decrease in fossil fuel stock utilization. Moreover, besides been hard to degrade they also undergo incomplete degradation caused by ultraviolet (UV) radiation, mechanical abrasion, and biological processes, producing microplastic polymer particles (Donato and Mija, 2019). There is plenty of motivation for that since the fossil-based thermoplastic polymers alone are responsible for about 13 million metric tons/year of direct contamination by polymeric solid residues. The increase in public environmental awareness, and consequent increase in regulation restrictions, has led to replacement of petrochemical monomers used in polyurethane industry by alternative monomers obtained from renewable sources, e.g., biomass, sugars or vegetable oils (Landim et al., 2019 Parcheta and Datta, 2017). ![]() Altogether, this study intends to provide engineers with new insights to obtain environmentally friendly TPU-based polymeric components (from prime materials to process methods), by associating the application of bio-based reactants to the TPU synthesis and understanding the conditions for these bio-TPUs been applied in low-waste processes such as additive manufacturing. Moreover, a coupled- Thermogravimetric analysis (TGA)-FTIR method provided useful information about thermal degradation and low molecular mass volatile products formed during the TPUs’ thermal decomposition. ![]() The TPUs’ chemical structure was analyzed by Fourier Transform Infrared Spectroscopy (FTIR-ATR) spectroscopy, the H-bonding fraction and crystallinity were examined by FTIR, Different Scanning Calorimetry (DSC), X-ray diffraction (XRD) and Polarized light optical microscopy (POM), and their processability was surveyed using the melt-flow index and Matrix-Assisted Laser Desorption/Ionization-Time of Flight Mass Spectrometry (MALDI-TOF-MS). ![]() This was achieved by varying the glycol type and molar ratio of / groups used during the prepolymer chain extending step. This work describes the preparation of bio-based thermoplastic poly(ether-urethane)s (TPU) via a prepolymer method and investigates the effect of varying the interphase hydrogen-bonding (H-bonding) on physicochemical, thermal and mechanical properties.
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