Unusual behavior in thermodynamical properties of chitosan-lanthanide oxide composites: competition between the size and mass

Abstract

Abstract The objective of this investigation is to explore how doping chitosan (Chi) with different lanthanide oxides (LnO) such as cerium, neodymium, samarium, europium, gadolinium, dysprosium, and holmium oxides affects its thermodynamic properties. Especially the effect of lanthanide contraction which is the competition between mass and size has been investigated and reported. The investigation describes a method for calculating various physical properties of a Chi-LnO composite material based on experimental values of refractive index, density, viscosity, and ultrasonic velocity concerning the mass and size of the LnO doped with chitosan. These properties play crucial roles in understanding the behavior and characteristics of composite materials. The process involves deriving the physical properties such as dielectric constant, intermolecular free path length, relaxation time, ultrasonic attenuation, relative association, surface tension, Gibbs free energy and non-linearity parameters are calculated from the experimental value of the refractive index, density, viscosity and ultrasonic velocity properties from the given experimental data and results are discussed in a detailed manner.