Experimental data and modeling of storage and loss moduli for a biosensor based on polymer nanocomposites

Abstract

The models for rheological properties such as storage and loss moduli are inadequate in literature, which cannot offer a suitable view. In this paper, the linear viscoelastic properties of the blends of poly (lactic acid) (PLA) and poly (ethylene oxide) (PEO) and nanocomposites of PLA, PEO and carbon nanotubes (CNT) are determined at dissimilar frequencies. Also, a general equation is advanced to forecast the storage and loss moduli of the samples by the complex modulus and relaxation time of elements. The forecasts of original and advanced models are linked to the empirical data. In addition, the parameters’ roles in the dynamic moduli of examples are justified to approve the developed model. The estimates of advanced model acceptably agree with the experimental facts at whole frequency range. The mixing of CNT with polymer blends increases the complex modulus and relaxation time of components. Moreover, high frequency of 30 rad/s and “a” exponent of 1.1 produce the maximum modulus of 30 Pa establishing that both frequency and “a” exponent directly manipulate the dynamic moduli of samples. Additionally, the maximum modulus of 35 Pa is achieved by G* = 1.1 Pa and λ = 70 s demonstrating that a high complex modulus and extended relaxation time of components improve the dynamic moduli. The advanced model can provide an easy procedure with meaningful parameters to predict the dynamic moduli for polymer mixtures and nanocomposites.