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

Abstract

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.POLYMER COMPOSITES-2019 FIG. 4. The relative viscosity as a function of (a) percolation threshold and (b) percentage of networked CNT according to Eq. 12 at average levels of parameters. [Color figure can be viewed at wileyonlinelibrary.com]

Calculation of the Electrical Conductivity of Polymer Nanocomposites Assuming the Interphase Layer Surrounding Carbon Nanotubes

“…The interphase as a different phase in polymer nanocomposites is commonly formed due to the outstanding surface area of nanoparticles, which causes strong interfacial interaction between polymer matrix and nanoparticles [37,38]. It was reported that the interphase regions positively affect the mechanical properties of polymer nanocomposites [39,40]. Therefore, many conventional models for mechanical performances of composites have been developed to consider the role of interphase [41,42].…”

Modeling the effect of interfacial conductivity between polymer matrix and carbon nanotubes on the electrical conductivity of nanocomposites

“…32,33 This occurrence is due to the incompatibility or less compatibility between polymer matrix and nanoparticles as well as the poor dispersion and agglomeration of nanoller in nanocomposites. [34][35][36] The extent of interfacial properties can also control the percolation threshold and conductivity of nanocomposites, because the super conductivity of nanoparticles should be transferred to surrounding polymer matrix. In fact, a strong interfacial adhesion can efficiently assign the ller conductivity to polymer matrix, whereas a poor interface cannot provide it.…”

Effects of carbon nanotubes and interphase properties on the interfacial conductivity and electrical conductivity of polymer nanocomposites

“…In our previous paper, we considered the interphase region as a separate phase in polymer nanocomposites and developed a simple equation for interphase conductivity using the interphase thickness, CNT conductivity and waviness parameter. Also, a simple model was developed for the conductivity of PCNTs assuming the conductivity of CNTs and the interphase region in that paper . In this study, the dimensions of the CNTs and the interphase thickness define the L c term.…”