Study on the Performance of Sucrose Modified Jatropha curcas Protein Adhesive

The study incorporated sucrose as a modifier to improve the bonding performance of the Jatropha curcas protein adhesive, achieved through normal temperature oxidation. Utilizing KMnO₄ oxidation, the excess hydroxyl groups of sucrose in the reaction were transformed into additional aldehydes, facilitating full crosslinking with the protein and thus forming the J. curcas protein adhesive. Dynamic thermomechanical analysis(DMA) and Fourier transform infrared spectroscopy(FTIR) instruments were used to analyze its thermal properties and structure. The results showed that with the increase of sucrose addition, the performance of J. curcas protein adhesive increased first, it also showed a decrease when the amount added was too much and the best sucrose dosage is 20%, the oxidation treatment protein adhesive has higher reactivity and excellent bonding performance when KMnO₄ is used as the oxidant, the additive amount is 12%, the oxidation time is 12 minutes, and the pH value is 7. Its the dry strength of plywood as high as 1.63 MPa, the 3 h 63 ℃ water soaking wet strength and 24 h cold water soaking strength were 0.84 MPa and 0.81 MPa, and that are all conformed the performance requirements of GB/T 9846—2015 for Type II plywood.