Preparation of Zinc Oxide Nanoparticles-Based Starch Paste and its Antifungal Performance as a Paper Adhesive

Zinc oxide nanoparticles (ZnO NPs) are used as antifungal agents and imparted in starch paste. The zinc oxide nanoparticles are synthesized using starch as a stabilizing agent under sonochemical irradiation, and then used in the preparation of ZnO NPs-based starch paste. The effects of starch and ultrasonic irradiation on the formation of ZnO NPs are subsequently investigated. Characterization by X-ray diffraction and transmission electron microscopy reveals that ZnO NPs synthesized under an optimal condition are highly dispersed and well-defined crystals with diameters of approximately 5 nm. The antifungal performance of ZnO NPs-based starch paste is evaluated under a high temperature and humidity environment, and is compared with traditional fungicides, alum, and pure terephthalic acid (PTA). In addition, the paste shows negligible toxicity and deterioration to the mechanical properties of the mounted paper. Lastly, the paper mounted with ZnO NPs-based starch paste shows superior antifungal performance, an essential property protecting paper documents from mold growth, compared to pristine starch paste.