Toward Utilization of Agricultural Wastes: Development of a Novel Keratin Reinforced Soybean Meal-based Adhesive

The development of low-cost bio-based formaldehyde-free adhesives has aroused widespread interest in the wood adhesive industry. In this study, a series of aldehyde-free adhesives were prepared from soybean meal (SM) and chicken feather (CF), which were both largely produced from agricultural wastes. Incorporation of 10 wt % of keratin and calcium phosphate oligomer (CPO) significantly reinforced the performance of the fabricated adhesive material (namely, SMK10-CPO10). The dry and wet bonding strength of SMK10-CPO10 improved to 3.01 and 1.46 MPa, which was 1.75 and 2.15 times that of the adhesive made with SM alone (1.72 and 0.68 MPa), respectively. Meanwhile, the viscosity of the adhesive decreased from 40.77 (SM alone) to 22.32 Pa.s (SMK10-CPO10), which apparently improved the fluidity and wettability of the protein-based adhesive. This work not only put forward a novel method to prepare the green high-performance bio-based adhesive but also opened up a new way for the utilization of waste resources and a new strategy for the design and synthesis of advanced structural and functional materials.

Automated summary

This study successfully prepared a formaldehyde-free adhesive using soybean meal and chicken feather as raw materials, significantly improving its performance by adding keratin and calcium phosphate oligomer. The dry and wet bonding strength of the fabricated adhesive increased by 1.75 and 2.15 times, while the viscosity decreased, improving fluidity and wettability.