LAUSR

A series of new bio-based aromatic diisocyanates, namely bis(4-isocyanato-2-methoxyphenoxy)alkane and bis(4-isocyanato-2,6-dimethoxyphenoxy)alkane, were synthesized starting from lignin-derived phenolic acids, namely vanillic acid and syringic acid, via the Curtius rearrangement. The diisocyanates were employed to synthesize poly(ether urethane)s by reacting them with potentially bio-based aliphatic diols, namely 1,10-decanediol and 1,12-dodecanediol. The chemical structures of diisocyanates and poly(ether urethane)s were confirmed using Fourier transform infrared, 1H NMR and 13C NMR spectroscopy. Inherent viscosities and number-average molecular weights of the poly(ether urethane)s were in the ranges 0.58–0.68 dL g−1 and 32 100–58 500 g mol−1, respectively, indicating the formation of reasonably high molecular weight polymers. The poly(ether urethane)s exhibited 10% weight loss in the temperature range 304–308 °C. The glass transition temperatures of the poly(ether urethane)s were in the range 49–74 °C and were dependent both on the number of methylene units in the diols and on the number of methoxy substituents on the aromatic rings of the diisocyanate component. © 2017 Society of Chemical Industry