Efficient Successive Route to Prepare Biobased Crystallizable Linear Non‐Isocyanate Polyurethanes With Sebacamide Segments

ABSTRACT Polyaddition of dicyclocarbonates with di‐ or multiamines is becoming an important route to synthesize non‐isocyanate polyurethanes (NIPUs) or polyhydroxyurethanes (PHUs). Biobased diglycerol dicyclocarbonate (DGDC) can be prepared easily from the cyclocarbonation of diglycerol with small alkyl carbonates. However, direct polyaddition of DGDC with aliphatic diamines often leads to low molecular‐weight linear PHUs with poor mechanical property. In this paper, several H 2 N‐terminated PHUs were synthesized first by a melt polyaddition of DGDC with 1,6‐hexamethylenediamine or 1,12‐dodecanediamine, and then linear non‐isocyanate polyurethanes with sebacamide segments (L‐NIPUSs) were prepared through a chain extension with dimethyl sebacate as the chain extender. The molecular weight was increased, and the T m and intermolecular forces were increased by the crystallizable sebacamide segments. The L‐NIPUSs showed good crystallization, high T m between 107°C and 146°C, and good tensile strength of up to 15 MPa. An efficient successive route was established to prepare biobased crystallizable NIPUs with good thermal and mechanical properties.