Magneto-mechano-optical properties of ultra-thin films built from mesogenic azo-polymers dopped with magnetic nanoparticles

• Grant number: 12/14945-4
• Support Opportunities: Regular Research Grants
• Duration: November 01, 2012 - October 31, 2014
• Field of knowledge: Physical Sciences and Mathematics - Physics - Classical Areas of Phenomenology and Applications
• Principal Investigator: Jean Jacques Bonvent
• Grantee: Jean Jacques Bonvent
• Host Institution: Centro de Ciências Naturais e Humanas (CCNH). Universidade Federal do ABC (UFABC). Ministério da Educação (Brasil). Santo André , SP, Brazil

Abstract

Smart materials are considered are of growing interest both for basic research and technological applications, mainly due to their specific response when submitted to external stimuli (thermal, electric, magnetic, luminous, etc). These materials can find applications in many areas such as artificial muscles, sensors, actuators, micro-robots or micro-pumps. In the case of liquid crystal elastomers (LCE) containing azodyes groups, there is a special combination of self-organization, strong anisotropy and elastic properties, that leads to shape and volume changes tending to occur anisotropically, when subjected to given temperatures (thermomechanical response) or to light irradiation (photomechanical response). The insertion of nanoparticles into these elastomers gives rise to a nanocomposite material known as magneto-optical, which shows a growing interest since the last decade, due to the exploration of the magnetic and optical properties of the nanoparticles together with the good processability of the polymer matrix, considering the possibility of activation of the system both by a magnetic field and light. These materials can find used in magnetic sensors, high-speed magneto-optical modulators as well as in information recording. The main purpose of the present project is to develop and study thin and free-standing ultra-thin films based on liquid-crystal polymers, azodyes and magnetic nanoparticles. Measurements will be performed to analyze the mechanical, morphological and optical properties of the different films, in order to achieve a better understanding the mechanisms involved in the LCE reorganization in the presence of azodyes and nanoparticles, when submitted to light and an magnetic field. (AU)

Scientific publications

(References retrieved automatically from Web of Science and SciELO through information on FAPESP grants and their corresponding numbers as mentioned in the publications by the authors)

ALAVARSE, ALEX CARVALHO; DE OLIVEIRA SILVA, FERNANDA WAITMAN; COLQUE, JANDIR TELLERIA; DA SILVA, VIVIAM MOURA; PRIETO, TATIANE; VENANCIO, EVERALDO CARLOS; BONVENT, JEAN-JACQUES. Tetracycline hydrochloride-loaded electrospun nanofibers mats based on PVA and chitosan for wound dressing. Materials Science & Engineering C-Materials for Biological Applications, v. 77, p. 271-281, AUG 1 2017. (12/14945-4)