Synthesis and characterization of conjugated polymers with different molecular weight and regio-regularities for the fabrication of nanostructures and chromic properties-based sensors

• Grant number: 10/13392-6
• Support Opportunities: Regular Research Grants
• Start date: November 01, 2010
• End date: April 30, 2013
• Field of knowledge: Physical Sciences and Mathematics - Chemistry - Organic Chemistry
• Principal Investigator: Debora Terezia Balogh
• Grantee: Debora Terezia Balogh
• Host Institution: Instituto de Física de São Carlos (IFSC). Universidade de São Paulo (USP). São Carlos , SP, Brazil

Abstract

Conjugated polymers generally show variation of light absorption spectrum depending on the properties of the medium (chromism), both in solution and in solid state in the form of films, which can be used in various types of sensors. These properties of the medium may be: the variation of pressure applied (piezochromism), interactions of specific parts of molecules with chemicals or biochemicals (biochromism), temperature (thermochromism), solvent (solvatochromism), the presence of ions (ionochromism), etc. Among the conjugated polymers, polytiophenes present some advantages over other systems such as: the easiness of chemical synthesis, the relative ease side chain funcionalization and more pronounced chromic properties. In addition to the side-chains, the way the repeating units connected in the polymer chain (regioregularity), the molecular weight and film morphology influences the chromic properties of the polymers. This project deals with the preparation of several polythiophenes with different side-chains, molar masses and degrees of regioregularity aimed at obtaining materials with differentiated chromic properties and nanostructured films for applications in optical sensors and in future photovoltaic devices. (AU)