Bonding performance of plywood with pig blood adhesives prepared by a novel method

Abstract

Renewable and eco-friendly pig blood adhesives (PBAs) were obtained by modifying PBAs with a mild alkaline solution and glutaraldehyde and exposing them to an ultrasound treatment. The PBAs were subjected to thermogravimetric (TG) analysis and Fourier transform infrared (FTIR) spectroscopy, and the bonding strength and bonding interface of plywood were analyzed to evaluate bonding performance. The results showed that the alkaline solution unfolded the structure of blood proteins, and the glutaraldehyde crosslinked the blood protein. In addition, the ultrasound greatly increased protein expansion under weak alkaline conditions. The thermal stability of the PBAs exposed to ultrasound treatment under weak alkaline conditions was improved, but the crosslinking agent was not used, and the permeability, which was analyzed by a fluorescence microscope, improved. Further, the average and effective penetration depths on the bonding interface increased 53% and 55%, respectively. The bonding strength of plywood prepared with modified PBAs was greatly improved and compliant with relevant requirements.