Engineering Composite of Silver Nanoparticles/Skim Natural Rubber/Bacterial Cellulose and Its Potential Application...

Biobased semiconducting composites composed of silver nanoparticles (AgNPs), skim natural rubber (SNR), and bacterial cellulose (BC) were fabricated by a green synthesis method. A solution of silver nitrate (AgNO₃) at concentrations of 40-160 mM was added to SNR latex to reduce silver ions to AgNPs at temperatures ranging from 50-80 °C for 8 h. Subsequently, a BC hydrofilm was immersed in the prepared AgNP-SNR latex suspension for 48 h before being washed and dried. The incorporation of SNR into BC enhanced the flexibility of the composite films. The strain at break of the films was significantly increased to 13.8% when the films were treated with 80 mM AgNO₃ at 80 °C. In addition, the electrical conductivity of the films was significantly increased to 4.09 × 10^-7 S/cm. In preliminary humidity sensitivity tests, owing to their high water absorption capacity, the films demonstrated fast response and recovery times of 3/20 (s/s) with a wide sensing range of humidity from 30% RH to 90% RH. The composite film of AgNP/SNR/BC demonstrated strong potential for use as a low-cost, robust, and flexible humidity sensor.