Synergistic effects of Uncaria gambir and zinc oxide in polyvinyl alcohol films for enhanced UV and blue light shielding, antimicrobial properties, and hydrophobicity: improving application performance in sustainable packaging and protective eyewear

Abstract

This study investigates the development and characterization of a novel composite material consisting of polyvinyl alcohol (PVA) integrated with Uncaria gambir (UG) and zinc oxide (ZnO) as fillers. The synergistic effects of UG and ZnO were investigated, focusing on their ability to enhance the film's properties. UV-vis spectrophotometry demonstrated that the composite film effectively blocked all UV (UV-A and UV-B) and blue light wavelengths. The mechanical properties were significantly enhanced, with tensile strength improving by 56% and elasticity by 38% compared to pure PVA. Additionally, water contact angle measurements showed an increase from 34.4° for pure PVA to 84.4° for the PVA/UG/ZnO composites, indicating a substantial improvement in hydrophobicity, which suggests the potential for extended application in environments where moisture resistance is crucial. These findings illustrate the potential of utilizing natural extracts and metal oxides in polymer composites for applications that require durable and effective protection against photodegradation and environmental factors. This study establishes a foundation for further exploration into biocompatible and environmentally sustainable materials with enhanced protective properties.