An aqueous polyisocyanate adhesive with excellent bond durability for engineered wood composites enhanced by polyamidoamine-epichlorohydrin co-crosslinking and montmorillonite hybridization. (January 2022)

• Record Type: Journal Article
• Authors: Fan, Bo; Kan, Haofeng; Kan, Yufei; Bai, Yumei; Han, Guangping; Bai, Long; Zhang, Shifeng; Gao, Zhenhua
• Is Part Of: International journal of adhesion & adhesives. Volume 112(2022)
• Publication Date: 2022-01
• Subjects: Polyisocyanate adhesive -- Bond durability -- Engineered wood composites -- Co-crosslinking -- Organic-inorganic hybridization; Adhesion -- Periodicals; Adhesives -- Periodicals; Adhésion (Physique) -- Périodiques; Adhésifs -- Périodiques; Adhesie; Kleefstoffen; Adhesion; Adhesives; Periodicals; 668.3
• DOI: 10.1016/j.ijadhadh.2021.103022
• Languages: English
• ISSNs: 0143-7496

Abstract

Abstract: Recent trends toward mass-timber buildings and tall timber structures necessitate more stringent requirements for the bond durability of adhesives for engineered wood composites. In this work, a cost-effective strategy for manufacturing a novel aqueous polyisocyanate adhesive with excellent hygrothermal resistance for engineered wood composites was produced via co-crosslinking with polyamidoamine-epichlorohydrin (PAE) resin followed by organic–inorganic hybridization with montmorillonite clay (MMC). Test results confirmed that PAE co-crosslinking effectively increased the crosslinking density of aqueous polyisocyanate adhesive meanwhile prolonged working life. Hybridization of PAE-crosslinked polyisocyanate with MMC resulted in compact crosslinked networks and notably increased hygrothermal resistance. Consequently, this novel aqueous polyisocyanate adhesive exhibited excellent bond durability of plywood in terms of a wet aged strength of 1.73 MPa and a strength reduction ratio of only 18.4% after 7 boiling-dry hygrothermal aging cycles, which satisfies the requirements for manufacturing engineered wood composites as good construction and building materials.