Bio‐Based Polyurethanes from Microbially Converted Castor Oil

• Published in: Journal of the American Oil Chemists' Society Vol. 96; no. 6; pp. 715 - 726
• Main Authors: Tran, Tuan Kiet, Kumar, Prasun, Kim, Hak‐Ryul, Hou, Ching T., Kim, Beom Soo
• Format: Journal Article
• Language: English
• Published: Hoboken, USA John Wiley & Sons, Inc 01.06.2019
• Subjects: Castor oil; Hydroxy fatty acid; Polyol; Polyurethane; Pseudomonas aeruginosa PR3
• ISSN: 0003-021X; 1558-9331
• DOI: 10.1002/aocs.12223

Bio‐based new polyurethanes (PU) were synthesized from microbially converted castor oil. Castor oil was used as a raw material to synthesize 7,10,12‐trihydroxy‐8(E)‐octadecenoic acid (TOD) by the strain Pseudomonas aeruginosa PR3. Subsequently, hexamethylene diisocyanate (HMDI) was used in different ratios and reacted with TOD to produce new PU. Fourier transform‐infrared spectroscopy, nuclear magnetic resonance spectroscopy, and gas chromatography/mass spectrometry were used to confirm the identity of TOD. Differential scanning calorimetry, thermogravimetric analysis, and tensile property testing were used to investigate the thermal and mechanical properties of PU. PU synthesized based on TOD had a tensile strength of 45.4 MPa with low elongation at break of 8.16% at an isocyanate/hydroxyl ratio of 2.0. To modify the properties of PU, TOD was blended separately with polyethylene glycol or polycaprolactone diol at different weight ratios before reacting with HMDI. The modified polymer showed improved thermal stability and comparatively higher elongation at break. This is the first study demonstrating the conversion of castor oil into TOD that can be used stand alone or as a blend for PU synthesis.