Synthesis and Characterization of Bio-Based Polyurea Derived from Liquefied Wood of Wooden Musical Instrument Offcuts

During the manufacturing of wooden musical instruments, offcut wood pieces are inevitably generated. This study explores the potential of utilizing three types of these small offcut wood pieces, mahogany, maple, and rosewood, by converting them into polyurea through liquefied wood technology by proposing a novel approach to synthesizing bio-based polyurea. This polyurea is a durable polymer, offering long-term carbon fixation and thereby contributing to environmental sustainability. In this study, various liquefaction conditions as parameters, including the temperature, sulfuric acid content, mix solvent ratio, and liquefaction time, were investigated in relation to polyurea film properties. The relationship between the mechanical and thermal properties of the resulting films and the characteristics of the liquefied product was investigated. Notably, when the hydroxyl value of the liquefied product exceeded 300, the resulting polyurea derived from the liquefied product exhibited a high tensile strength of 25 MPa. In contrast, when the hydroxyl value was below 300, the polyurea derived from the liquefied product displayed a strain value of up to 150%, alongside an increased thermal decomposition temperature. These findings suggest that the properties of polyurea can be effectively tuned by manipulating the characteristics of the liquefied product, offering a promising approach to enhancing the value of offcut wood in instrument manufacturing.