In-situ modification of low molar ratio urea–formaldehyde resins with cellulose nanofibrils for plywood. Issue 22 (17th November 2021)

• Record Type: Journal Article
• Authors: Wibowo, Eko Setio; Lubis, Muhammad Adly Rahandi; Park, Byung-Dae
• Is Part Of: Journal of adhesion science and technology. Volume 35:Issue 22(2021)
• Page Start: 2452
• Page End: 2465
• Publication Date: 2021-11-17
• Subjects: Urea–formaldehyde resins -- cellulose nanofibrils -- in-situ modification -- activation energy -- adhesion -- formaldehyde emission; Adhesion -- Periodicals; Adhesives -- Periodicals; 668.3
• DOI: 10.1080/01694243.2021.1890370
• Languages: English
• ISSNs: 0169-4243

Abstract

Abstract: This study describes the in-situ modification of low molar ratio urea–formaldehyde (UF) resins with cellulose nanofibrils (CNFs) to improve the poor performance of resins synthesized with different methods (Synth 1 and Synth 2) when adding second urea. UF resins were in-situ modified with CNFs dissolved in a mixture of dimethyl sulfoxide (DMSO) and dimethylformamide (DMF) during the alkaline reaction step. Results showed that CNF addition enhanced the resin properties, such as shorter gelation time, faster curing rates at low activation energy, higher tensile shear strength (TSS), and lower formaldehyde emission (FE), compared to those of neat resins. The dry and wet TSS values of plywood bonded with UF resins modified with 3% CNFs synthesized using Synth 2 increased by 30% and 42%, respectively, and the FE value was decreased by 22% and 42%, respectively. These results reveal that in-situ modified UF resins with CNFs showed better performance than neat UF resins and that Synth 2 was more favorable than Synth 1.