Effects of interphase regions and filler networks on the viscosity of PLA/PEO/carbon nanotubes biosensor

The present work suggests a simple model for viscosity of polymer carbon nanotubes (CNT) biosensor assuming CNT concentration, CNT dimensions, interphase thickness, and network size. CNT concentration, CNT size, and interphase thickness express the effective filler concentration and the percolation threshold, which determine the fraction of networked CNT in nanocomposite biosensors. The experimental results of viscosity for the prepared samples containing poly(lactic acid) (PLA), poly(ethylene oxide) (PEO), and carbon nanotubes (CNT) are measured to approve the suggested model. Moreover, the developed model presents the roles of all parameters in the viscosity to confirm the predictions. The predictions properly agree with the experimental data of samples demonstrating the predictability of the developed model. Thin and large CNT (high aspect ratio) mainly increase the viscosity, while thick or short CNT produce very low viscosity. A high CNT concentration and thick interphase significantly enhance the viscosity, while a low content of CNT or a thin interphase cause an extremely low viscosity. In addition, the percentage of CNT in the networks directly manipulates the viscosity. POLYM. COMPOS., 40:4135–4141, 2019. © 2019 Society of Plastics Engineers