materials Article Improvement in Wood Bonding Strength of Poly (Vinyl Acetate-Butyl Acrylate) Emulsion by Controlling the Amount of Redox Initiator Yun Zhang 1, Bo Pang 1, Sen Yang 1, Wei Fang 1, Sheng Yang 2, Tong-Qi Yuan 1,* and Run-Cang Sun 1 1 Beijing Key Laboratory of Lignocellulosic Chemistry, Beijing Forestry University, No. 35 Tsinghua East Road, Haidian District, Beijing 100083, China;
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[email protected]; Tel.: +86-10-6233-6903 Received: 18 December 2017; Accepted: 5 January 2018; Published: 8 January 2018 Abstract: Polyvinyl acetate emulsion adhesive has been widely used due to its good bonding performance and environmentally friendly properties. Indeed, the bonding performance can be further improved by copolymerizing with other monomers. In this study, the effect of the adjunction of redox initiator (hydrogen peroxide–tartaric acid, H2O2–TA) on the properties of the poly (vinyl acetate-butyl acrylate) (P (VAc–BA)) emulsion adhesive was investigated. With increasing dosage, the reaction became more complete and the obtained film was more compact, as identified via SEM. The core-shell structure of the emulsion particles was confirmed via TEM. Results indicate that while the initiator content increased from 0.5 to 1.0%, a clearer core-shell structure was obtained and the bonding strength of the plywood improved from 2.34 to 2.97 MPa.