Developing a high-strength antibacterial soy protein adhesive by adding low amount of tetraepoxy l-tyrosine. (August 2022)

• Record Type: Journal Article
• Authors: Lei, Zhenghui; Jiang, Ke; Chen, Yuzhu; Qi, Jinqiu; Xie, Jiulong; Huang, Xingyan; Jiang, Yongze; Zhang, Shaobo; Jia, Shanshan; Xiao, Hui
• Is Part Of: Polymer testing. Volume 112(2022)
• Publication Date: 2022-08
• Subjects: Soy protein adhesive -- Tetraepoxy l-tyrosine -- Antibacterial -- Shear strength -- Mold resistance; Polymers -- Testing -- Periodicals; Polymères -- Tests -- Périodiques; 620.1920287
• DOI: 10.1016/j.polymertesting.2022.107643
• Languages: English
• ISSNs: 0142-9418

Abstract

Abstract: Although soy protein (SP) adhesives have shown great potential in promoting the green and sustainable development of the wood industry, the practical application of SP adhesives is limited by poor performance (bonging strength, mold resistance and water resistance). Cross-linking modification is considered to be the most effective modification method for SP adhesives. In this work, non-antibacterial l -tyrosine (TYR) was treated with epichlorohydrin to graft multiple epoxy groups and transformed into tetraepoxy l -tyrosine (ETY). Interestingly, ETY exhibited obvious antifungal properties with a bacteriostatic rate as high as 98.3%. Adding a low amount (3 wt%) of ETY, the wet shear strength of the modified adhesive was 169.1% higher than that of the pristine SP adhesive, reaching 1.83 MPa. Moreover, in an environment of 28 °C and 80% humidity, both uncured and cured SP adhesives (with 3 wt% ETY) exhibited an anti-mold period of more than 30 days. Therefore, this work reveals that non-antibacterial bio-based materials may be endowed with antibacterial properties through epoxidation and transformed into multifunctional modifiers, and provides a new way for the development of high-strength antibacterial bio-based adhesives. Highlights: Non-antibacterial bio-based materials may be endowed with antibacterial properties through epoxidation. The antibacterial rate of tetraepoxy l -tyrosine is as high as 98.3%. High performance adhesive modified by low amount of ETY. The wet shear strength of the adhesive (with 3 wt% ETY) increased by 169.1% to 1.83 MPa. Modified adhesives (with 3 wt% ETY) showed an anti-mold period of more than 30 days.