Preparation and characterization of polyurethane plasticizer for flexible packaging applications: Natural oils affirmed access

Developing bio-renewable feedstock for polyurethane (PU) manufacturing and polymer industry as a whole has become highly desirable for both economic and environmental reasons. In this work castor oil (CO) and palm olein (PO) polyols were synthesized and partially used as renewable feedstock for the manufacturing of polyurethane plasticizing resin for printing ink applications. The chemical structure of the prepared polyols and polyurethanes were characterized using IR spectra and GPC and their solubility in common solvents was tested. As well, properties such as flexibility, mechanical properties, optical properties, heat seal and freeze resistance of these prepared printing inks were determined. The results indicated that the prepared printing inks from 50% synthesized polyurethane have high thermal stability, adhesion and excellent freeze resistance. The net technical properties of the new ink formulations are relatively comparable to the printing ink prepared from standard polyurethane plasticizer.