A series of hyperbranched polyesters were incorporated by the chemical reaction of the dimethylolpropionic acid with trimethylolpropane, pentaerythritol, and glycerol as the core group. The castor oil-based fatty acids were also successfully prepared in order to examine the impact of the biopolyols on the thermo-mechanical characteristics of the waterborne hyperbranched polyurethane. The chemical structure of the polyols and the resulting polymer were characterized. Developing −OH functionality of the polyols the polyurethanes represented an improvement in crosslinking density, leading to increasing Tg, tensile modulus, and tensile strength and a decrease in elongation and toughness. Thus, the overall results forward the synthesized HBWPU as a potent sustainable and eco-friendly polymeric material by a simple approach that possesses a higher degree of sustainability over a purely petrochemical route.
Available online 23 February 2018