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The optimization of manufacturing conditions for reed straw-based particleboard by soy-based adhesive was performed through response surface methodology. The interactions of various conditions, including adhesive amount, hot-pressing temperature, and hot-pressing time on wet internal bonding strength were investigated. A 3-level-3-factor Box–Behnken design was used to test the optimal preparation conditions of reed straw particleboard. The polynomial regression model for manufacturing conditions had a very significant level ( p < 0.01 ). In addition, the determination coefficient (R2) and the adjust determination coefficient ( R 2 ) of this model were found to be 0.969 and 0.9292, respectively. The conditions optimized by the model were 25% of adhesive amount, 138°C of hot-pressing temperature, and 27 min of hot-pressing time. Under the optimal conditions, validation tests were performed, and the average value of parallel experiments was 0.17 ± 0.02 MPa. Moreover, the thickness swelling of water absorption after soaking and mechanical properties (MOE and MOR) of samples prepared under optimized conditions were further measured, which all met the requirement of Type P6 particleboard. It could provide an efficient method for massive production of reed straw particleboard.

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In this paper, thermogravimetric (TG) analysis was carried out to make clear the curing properties of soy flour-based adhesives (SFAs) enhanced by waterborne polyurethane (WPU) with different addition levels. The kinetic parameters were evaluated by a thermal dynamics method, including activation energy and preexponential factor. In addition, the structure characteristics of both soy flour and modified soy flour-based adhesives were tested by Fourier transform infrared spectroscopy (FTIR). The results revealed that the FTIR spectra of pristine soy flour-based adhesives were different from those of soy flour after alkali treatment and waterborne polyurethane modification. Furthermore, there were four main degradation phases in the derivative thermogravimetric (DTG) curves of modified soy-based adhesives while there were two phases of a defatted soy flour sample. The kinetics analysis demonstrated that the curing process could be described as a consecutive first-order curing process. Moreover, with the addition level of WPU growing, the apparent activation energy of each phase of the curing process was increasing compared with that in pristine soy-based adhesives.