Utilization Of Styrene Acrylic Emulsion In Preparation Of Poplar Plywood And In Veneering Of Wheat Straw Particleboard

Currently,plywoods are mainly produced with formaldehyde-based adhesives,which are derived from non-renewable oil resources,and will release formaldehyde that is harmful for human body during the production and use of plywoods.Therefore,study on the application of environmentally-friendly adhesives in plywoods has great practical and environmental significance.In this paper,the manufacturing process of poplar veneer and styrene acrylic latex-bonded plywoods was studied.The optimum technological parameters of the plywood production were analyzed.Then,some fillers were then added into the styrene acrylic latex to reduce the cost of adhesive.The best technology with both economic efficiency and quality was determined.(1)By studying the technological parameters such as hot pressing temperature,hot pressing pressure,hot pressing time and sizing amount,the optimum technological parameters of the second generation plywood of styrene-acrylic latex were studied.The mechanical properties and environmental performance of the plywood were evaluated by measuring the gluing strength,flexural strength and elastic modulus,formaldehyde content.The interfacial bonding morphology of the poplar veneer/styrene acrylic emulsion plywood with different sizing amount was observed by scanning electron microscopy The The results show that the bonding strength is optimal when the temperature is 130 ℃,the time is 5min,the sizing amount is 280g/m2 and the pressure is 1.0Mpa.(2)Two-component styrene-acrylic latex and poplar veneer made in accordance with the national Class Ⅱ standard plywood,to explore the impact of batter on the bonding strength and evaluate its mechanical properties and environmental performance.Experiments show that the combination of styrene acrylic and batter two-component adhesive in the best process and the green wood plywood made of plywood bonding strength has reached 1.47Mpa,30%of the batter added also reached 0.77Mpa,performance Excellent.(3)Veneering tests for isocyanate-bonded wheat straw particleboards were performed by using Fraxinus mandshurica and two-component styrene acrylic latex.The environmental performance and mechanical properties of the boards were evaluated through the surface bonding strength tests,and the immersion and peeling tests.The results showed that the stripping was not found for the boards coated with adhesive containing over 65%of styrene acrylic latex.The styrene acrylic latex had excellent water resistance,which was suitable for veneering.This result could be converted into an excellent production process.