Chitosan-Based Adhesive: Optimization of Tensile Shear Strength in Dry and Wet Conditions

Commercial adhesives present a high bond strength and water resistance, but they are considered non-healthier products. Chitosan can be as an interesting biosourced biodegradable alternative, despite its low resistance. Here, wood bonding implementation tensile shear in dry wet conditions were investigated depending on structural characteristics. Firstly, the spread rate, open assembly time, drying pressure, temperature, time have been determined for two chitosans of European pine double lap specimens. An adhesive solution rate 1000 g·m?2, 10 min, pressure temperature 55 °C 105 min led to 2.82 MPa. Secondly, comparison between molecular weight/low deacetylation degree chitosan lower weight/higher was conducted. Tests conducted with beech simple specimens accordance conditioning treatments environments required thermoplastic standards used non-structural applications (EN 204 EN 205). The results clearly revealed dependence properties resistance features (molecular weight degree), explaining heterogeneity published notably this field.