title: Monitoring molecular dynamics of bacterial cellulose composites reinforced with graphene oxide by carboxymethyl cellulose addition.
abstract: Broadband Dielectric Relaxation Spectroscopy was performed to study the molecular dynamics of dried Bacterial Cellulose/Carboxymethyl Cellulose-Graphene Oxide (BC/CMC-GO) composites as a function of the concentration of CMC in the culture media. At low temperature the dielectric spectra are dominated by a dipolar process labelled as a β-relaxation, whereas electrode polarization and the contribution of dc-conductivity dominate the spectra at high temperatures and low frequency. The CMC concentration affects the morphological structure of cellulose and subsequently alters its physical properties. X-ray diffractometry measurements show that increasing the concentration of CMC promotes a decrease of the Iα/Iβratio. This structural change in BC, that involves a variation in inter- and intramolecular interactions (hydrogen-bonding interactions), affects steeply their molecular dynamics. So, an increase of CMC concentration produces a significantly decrease of the β-relaxation strength and an increase of the dc-conductivity.
authors.affiliation: Department of Applied Thermodynamics, Institute of Electric Technology, Universitat Politècnica de València, Valencia, Spain. Electronic address: jsanchis@ter.upv.es.
authors.forename: M J
authors.initials: MJ
authors.lastname: Sanchis
authors.affiliation: Department of Applied Thermodynamics, Institute of Electric Technology, Universitat Politècnica de València, Valencia, Spain; Instituto de Automática e Informática Industrial, Universitat Politècnica de València, 46022 Valencia, Spain.
authors.forename: M
authors.initials: M
authors.lastname: Carsí
authors.affiliation: Departament de Química Física, Institut de Ciència dels Materials, Universitat de València, Valencia, Spain.
authors.forename: C M
authors.initials: CM
authors.lastname: Gómez
authors.affiliation: Departament de Química Física, Institut de Ciència dels Materials, Universitat de València, Valencia, Spain.
authors.forename: M
authors.initials: M
authors.lastname: Culebras
authors.affiliation: Department of Mechanical Engineering, Pontificia Universidad Católica del Peru, Lima 32, Peru.
authors.forename: K N
authors.initials: KN
authors.lastname: Gonzales
authors.affiliation: Department of Mechanical Engineering, Pontificia Universidad Católica del Peru, Lima 32, Peru.
authors.forename: F G
authors.initials: FG
authors.lastname: Torres
mesh_terms: D002266:Carboxymethylcellulose Sodium / Q000737:chemistry*; D002482:Cellulose / Q000737:chemistry*; D006108:Graphite / Q000737:chemistry*; D056004:Molecular Dynamics Simulation; D010087:Oxides / Q000737:chemistry*
chemical_list: D010087:Oxides; D006108:Graphite; D002482:Cellulose; D002266:Carboxymethylcellulose Sodium
keywords: Bacterial cellulose composites; Dielectric relaxation spectroscopy; Thermal stability