Producing Jatropha oil-based polyol via epoxidation and ring opening

A low viscosity polyol has been functionalized from crude Jatropha oil via epoxidation and subsequent ring-opening. Starting with the crude Jatropha oil, the double bonds are functionalized by introducing epoxy groups and ring-opened to produce hydroxyl groups. The experiment employs more concentrated 50% hydrogen peroxide and effectively produce solvent-free epodixidized Jatropha oil within shorter reaction time of 5 h with maximum oxirane oxygen content of 4.30% and viscosity of 0.57–0.60 Pa.s. The epoxidized Jatropha oil is then transform into Jatropha-based polyol with hydroxyl number of 171–179 mg KOH/g, low viscosity of 0.92–0.98 Pa.s. and functionality of 5.1–5.3. The epoxidation and ring-opening process are monitored by viscometer and FTIR. The produced polyol permit more time for molding and additives addition during polyurethane due to its low viscosity

Understanding intrinsic plasticizer in vegetable oil-based polyurethane elastomer as enhanced biomaterial

Renewable polyol is of increasing interest as a building block in biomedical elastomer for bearing biodegradable ester group and immaculate functionality. Derived from non-edible vegetable oil, a new class of elastomer was successfully functionalized with MDI and TDI. Crosslink densities were varied by regulating ratio of hydroxyl to diisocyanate (r) at 1/1.0, 1/1.1, and 1/1.2. Produced elastomers were examined by crosslink density, attenuated total reflectance Fourier transform infrared spectroscopy, differential scanning calorimetry, thermogravimetric analysis, dynamic mechanical analysis, tensile testing, and scanning electron microscopy. The obtained elastomers had subambient glass transition temperature (T g) suggested majority soft segment that acted as a continuous phase with intermediate phase separation. Medium conversion at gel point had enhanced physical properties. Highly elastic mechanical behavior was afforded from combination of side chains and high molecular weight polyol. At r = 1/1.2, MDI-based elastomer showed twofold improvement in Young modulus at slight expense of elongation. TDI-based elastomer accomplished elongation beyond 162%. Branching allophanate and biuret resisted early thermal breakdown by elevating activation energy. Frequency response and kinetic of thermal degradation provided beneficial perspective for elastomer characterization. The vegetable oil-based polyurethane was found able to resemble most of the physical properties of polycaprolactone (PCL)-derived polyurethane

Synthesis and characterization of Jatropha-based polyurethane from Jatropha-based polyol

A new vegetable oil-based polyol has been successfully functionalized for polyurethane fabrication. Starting with the crude jatropha oil, the double bonds are functionalized by introducing epoxy groups and followed by ring opening step to produce hydroxyl groups. This method effectively produced solvent-free epodixidized jatropha oil at rapid reaction kinetic with maximum oxirane oxygen content of 4.3%. This chemical synthesis scheme provides low viscosity and moderate functionality polyol with easier route to produce flexible film of vegetable-based polyurethane at reasonable material properties with hydroxyl number of 171 - 180 mg KOH/g, viscosity of 0.92 - 0.98 Pa.s and functionality of 5. The jatropha oil-based polyol is then reacted with aromatic diisocyanate to produce jatropha oil-based polyurethane in the present of catalyst dibutyltin dilaurate. Three distinct regions have been observed in the reactivity test of polyurethane formation corresponding to reaction of hydroxyl and isocyanate groups and branching processes. The glass transition temperature of -55 to -45 oC suggested that existence of majority flexible/soft segments and exhibited rubber-like behavior in stress-strain measurement with tensile stress at break between 2 - 6 MPa and elongation at break of 110 - 193%. Fractography evidence by SEM showed relatively flat surface with ridges and V-shaped "chevron" marking. Jatropha oil-based polyurethane is thermally stable with the onset for thermal degradation is in the range of 233 - 277 oC followed by char formation. Pseudo-plastic flow behavior with index of 0.09 - 0.24 is observed in dynamic mechanical analysis. However high amount of acid (> 0.1 mg KOH/g) in the polyol is detrimental to the branching processes with evidence of relatively low glass transition temperature (-50 oC) and mechanical strength (2 MPa)