Preparation, characterization and properties of starch-based wood adhesive

A new biodegradable, renewable, environmentally friendly starch-based wood adhesive that can be used at room temperature was synthesized by the graft polymerization of vinyl acetate monomer onto waxy corn starch. Compared with the blend of commercial PVAc/gelatinized starch, the shear strength of grafted starch adhesive increased by 59.4% in dry state and 321% in wet state, while its water resistance increased by 61.1%. The improved performance of the grafted starch-based wood adhesive was supported by its strengthened compatibility with polyvinyl acetate and starch, based on the results of Fourier-transform infrared, 1H nuclear magnetic resonance, thermogravimetry, and scanning electron microscopy analyses. The most economic monomer feeding ratio was also evaluated using bond characteristics and grafting parameters. A starch/monomer ratio of 1:1.2 (w/w) was considered as the best ratio in terms of economy.