Polyols and polyurethanes from renewable sources: past, present and future—part 1: vegetable oils and lignocellulosic biomass

• Published in: JCT research Vol. 19; no. 1; pp. 201 - 222
• Main Authors: Malani, Ritesh S., Malshe, Vinod C., Thorat, Bhaskar Narayan
• Format: Journal Article
• Language: English
• Published: New York Springer US 2022; Springer Nature B.V
• Subjects: Biomass; Chemistry and Materials Science; Commercialization; Corrosion and Coatings; Hydroxyl groups; Industrial Chemistry/Chemical Engineering; Isocyanates; Lignocellulose; Materials Science; Petroleum products; Polymer Sciences; Polyols; Polyurethane foam; Raw materials; Review Article; Surfaces and Interfaces; Synthesis; Thin Films; Tribology; Vegetable oils; Isocyanates; Renewable feedstock; Seed oil; Biomass; Polyols; Polyurethanes
• ISSN: 1547-0091; 1935-3804; 2168-8028
• DOI: 10.1007/s11998-021-00490-0

Polyurethanes, a major class of polymers conventionally derived from petroleum products, find applications in numerous sectors. Limited fossil resources, their extensive usage, large carbon footprint and alarming environmental issues motivated the research community worldwide in finding alternate and renewable routes for one of the key raw materials, polyols and isocyanate precursors. There are several reports available in the literature showing the techno-economic viability of bio-based polyols and hence polyurethanes. This article summarizes the synthesis of renewable polyols and polyurethanes thereof through utilization of various renewable sources such as vegetable oils, lingo-cellulosic biomass and other feedstock. The polyols obtained from different starting materials lead to variation in hydroxyl number and ultimately have a profound impact on the properties of polyurethanes. Hydroxyl groups are further classified based on their presence in polyols. Primary hydroxyl groups present in polyols hold the mechanical and thermal performance of final polyurethanes better. In this context, the recent advancements in increasing the primary hydroxyl groups in bio-based polyols through different chemical transformation has been focused on here. Moreover, the developments in the synthesis of polyurethane foam without the use of isocyanates have been considered as a green polymer. The ever-increasing demand in the market and the high potential of renewable sources will lead to further advancement in commercialization of bio-based polyurethanes.