Biobased Carbohydrate-Based Linear Aliphatic Polyesters Containing Acetyl-Protected Sorbitol, Mannitol, and Xylitol: Synthesis and Their Thermal, Tensile Properties

Development of functional polymers from biorenewable resources has been considered as an important subject in terms of circular economy. High molecular weight biobased aliphatic polyesters (Mn = 53900–65600 g/mol) consisting of bis(undec-10-enoate) of acetyl-protected D-sorbitol, D-mannitol, and of D-xylitol have been prepared by acyclic diene metathesis (ADMET) polymerization using molybdenum–alkylidene catalyst in toluene; subsequent olefin hydrogenation gave the saturated polyesters without significant decreases in the Mn values (Mn = 55300–64900 g/mol). The resultant saturated polyesters containing sorbitol and xylitol were semicrystalline materials possessing melting temperature at 17.1 and 14.3 °C, respectively, whereas the polyester containing mannitol was amorphous. The mechanical properties (tensile stress and elongation at break) of the resultant polymer film containing sorbitol displayed a unique contrast to that containing the reported isosorbide-based polyester and showed unique elongation at break (1580%). The mechanical properties in the polymer films containing mannitol and xylitol were improved by preparing the composite materials with a small amount of cellulose nanofiber (1.0 wt %).