Fabrication of degradable and high glass-transition temperature thermosets from palm oil and isosorbide for fiber-reinforced composites

Inexpensive, abundant, and low iodine value palm oil (PO) from oil palm (Elaeis guineensis Jacq.) was utilized to formulate biobased polymer matrices for fiber-reinforced composites. A reactive PO fatty acid-ethyl acrylamide (POFA-EA) was synthesized from PO and N-(2-hydroxyethyl)acrylamide (HEAA) via a benign transesterification. Another glucose-derived monomer, i.e., isosorbide was used to react with methacrylate anhydride to synthesize a comonomer, isosorbide-methacrylate (IM). Then, a new class of renewable, property-tunable, and degradable PO-based thermosets were prepared from flexible POFA-EA and rigid IM. The cross-linked POFA-EA/IM resins had suitable processability for composites, high glass transition temperatures (T(g)s) (150-204 degrees C), and superior mechanical strengths and moduli, while maintaining high biobased contents (similar to 60 %). The PO-based thermoset composites reinforced by kenaf, bamboo, glass, and carbon fibers, respectively, exhibited higher T(g)s (136-193 degrees C) than their petroleum-based counterparts. Meanwhile, the PO-based matrices can be decomposed in a mild alkali solution, which provides a feasible way to recycle high performance reinforcements such as carbon fibers.

Automated summary

This study focuses on utilizing inexpensive palm oil to prepare renewable, property-tunable, and degradable thermoset resins for fiber-reinforced composites, which exhibit high strengths and moduli. These palm oil-based matrices can be decomposed in a mild alkali solution for recycling high-performance reinforcements.