Carbon Nanotubes in Composite Hydrogels Based on Plant Carbohydrates

Abstract

Due to the physical, chemical, biological characteristics and high biocompatibility, the hydrogels based on plant polysaccharides and proteins became a sought-after material in many fields. Such hydrogels are the water swelling biopolymer matrices that react reversibly on minor changes in composition and in the external environment. However, the mechanical and electrical properties of "pure" hydrogels inhibit their wide practical application. One of approachs to improve their properties is the usage of carbon nanotubes, which provide good electrical conductivity and can significantly improve the characteristics of materials. The effects of carbon nanotubes on electric conductivity and mechanic properties of hydrogels based on natural biopolymers (gelatin and κ-carrageenan) of different composition were investigated. The electrical conductivity of the gels was studied using InoLab Cond 7310 SET1 conductometer. The rheological properties of hydrogels were investigated by Anton Paar MCR 302 rheometer. Such characteristics as temperature, frequency and amplitude dependencies of the storage modulus and the loss modulus of hydrogels were obtained. It was found that the addition of carbon nanotubes led to the increase in electrical conductivity of hydrogels. The morphology and rheological properties of studied hydrogels alter significantly in the presence of carbon nanotubes. The obtained data indicate the possibility of a purposeful change in electrical and mechanical properties of hydrogels by the addition of carbon nanotubes.