Non-traditional vegetable oil-based isocyanate-free polyurethane: a short review

The conventional use of polyurethane in various applications is hindered by significant challenges, such as toxicity concerns, moisture sensitivity, and environmental impact. In response, there has been a notable surge in research focusing on bio-based alternatives, particularly non-isocyanate polyurethanes (NIPUs), aligning with sustainable development objectives. NIPUs offer a promising solution by eliminating the need for isocyanates, employing cyclic carbonates and diamines instead. Out of various sources available, non-traditional vegetable oils present a viable starting material for cyclic carbonate synthesis due to their availability, renewability, and affordability. However, despite the growing interest in NIPUs, there remains a scarcity of literature on the utilization of non-traditional oils for their development. This short review aims to fill this gap by providing an overview of bio-based NIPUs synthesized from non-traditional vegetable oils such as jatropha oil, castor oil, lignin oil, linseed oil, and rubber seed oil. The review covers the synthesis methods of NIPUs via polyaddition reactions of carbonates and amines, detailing properties, advantages, and applications of each oil-based NIPU. Furthermore, by identifying research gaps and proposing potential solutions, this paper aims to encourage researchers to consider non-traditional oils for NIPU synthesis, facilitating significant advancements in the field. {GRAPHIACAL ABSTRACT}