Synthesis and characterization of polyurethanes with high renewable carbon content and tailored properties.

Abstract

Thermoplastic and cross-linked biobased polyurethanes with a renewable carbon content ranging from 78 to 98% were synthesized and characterized. The macrodiol and the diisocyanate used were derived from renewable source, the first from castor oil and the second from fatty acid. Moreover, the chain extenders employed were derived from corn sugar and polysaccharides. The effect of component molar ratios and chain extender and cross-linker structure on the final properties was analyzed. Thermal analysis revealed that polyurethanes are formed by amorphous and crystalline domains. It was also observed that the crystallinity of the material is related to the molar ratio of the components and also their structure. Besides, mechanical properties and morphology were tightly dependent on the overall crystallinity, allowing the synthesis of biobased polyurethanes with tailored properties and high renewable carbon content.