Development and characterization of sustainable biodegradable wood adhesive using starch as the main ingredient

Starch-based wood adhesives are becoming more and more popular as a result of the growing need for eco-friendly adhesives. However, lower performance currently limits the use of native starch-based wood adhesives in commercial scale. This study aimed to develop and evaluate a sustainable starch based wood adhesive by incorporating clay particles as fillers. A two-factor factorial design was used, where the first component was the clay-to-starch ratio, which had three different levels of 0.5:1, 0.2:1, and 0.3:1 w/w, and the second factor was the plasticizer (glycerol)-to-starch ratio, which had three levels of 2.5:1, 5:1, and 7.5:1 w/v. The physicochemical and thermomechanical properties of adhesive were investigated. The experimental analysis revealed that the optimal viscosity was found to be 3.11 +/- 0.31 cp at a temperature of 75 degrees C, moisture uptake was 0.82 +/- 0.043 at 12% clay content and 10% plasticizer content. The optimum value of tensile strength was 3.45 +/- 0.22MPa at 8% filler content and 20% plasticizer content, at the same values of filler and plasticizer content, the optimal shear strength obtained was 3.135 +/- 0.170 MPa in the dry state and 1.105 +/- 0.02 MPa in the wet state. The best adhesive properties were achieved with a fillers-to-plasticizer ratio of 1:5.