Investigation of mechanical and electrochemical properties of organic-inorganic siloxane-PMMA hybrid films applied for corrosion protection of metallic surfaces

• Grant number: 13/00295-0
• Support Opportunities: Scholarships abroad - Research Internship - Master's degree
• Start date: April 01, 2013
• End date: September 30, 2013
• Field of knowledge: Engineering - Materials and Metallurgical Engineering - Nonmetallic Materials
• Principal Investigator: Peter Hammer
• Grantee: Fábio Cesar dos Santos
• Supervisor: Marie-Joëlle Menu
• Host Institution: Instituto de Química (IQ). Universidade Estadual Paulista (UNESP). Campus de Araraquara. Araraquara , SP, Brazil
• Institution abroad: Université Paul Sabatier - Toulouse III, France
• Associated to the scholarship: 11/16800-0 - Development of multifunctional systems based on doped organic-inorganic hybrids compounds, BP.MS

Abstract

Organic-inorganic hybrid coatings prepared by sol-gel process are considered as a good alternative for the protection of metal surfaces against corrosion, replacing chromium-based compounds that present environmental problems due to its high toxicity. Based on the versatility of these materials, this work aims at the preparation and structural optimization of hybrid organic-inorganic coatings used for corrosion protection of metallic surfaces. The organic-inorganic hybrid coatings are prepared via radical polymerization of MMA (methyl methacrylate) and MPTS (3-metacriloxipropril trimethoxy silane) followed by hydrolysis and poly-condensation catalyzed by acid of TEOS (tetraethoxy silane) and the silane part of MPTS and deposited by dip-coating on carbon steel. The current results indicate that the hybrids have high inorganic network connectivity (> 85%) and high thermal stability. Electrochemical impedance spectroscopy and polarization curves show that the coatings have resistance greater than 1 G© and current densities lower than 10-9 Acm-2 against aggressive media (saline and saline / acid). In this part of the work aims to optimize the synthesis conditions and correlate the mechanical and electrochemical properties (hardness, wear, adherence to the nanostructural characteristics, using nuclear magnetic resonance (NMR) spectroscopy photoelectron (XPS / UPS), infra red (FTIR) and Raman. (AU)