Identification of structural patterns in polyurethane-silica hybrid and their correlation with high performance coatings

• Grant number: 24/15192-7
• Support Opportunities: Scholarships in Brazil - Scientific Initiation
• Start date: March 01, 2025
• End date: February 28, 2026
• Field of knowledge: Physical Sciences and Mathematics - Chemistry - Physical-Chemistry
• Principal Investigator: Sandra Helena Pulcinelli
• Grantee: Natália Violato Gon
• Host Institution: Instituto de Química (IQ). Universidade Estadual Paulista (UNESP). Campus de Araraquara. Araraquara , SP, Brazil

Abstract

The need to reduce the use of petroleum-derived materials in favor of inexhaustible raw materials is increasingly urgent, making organic-inorganic hybrids (OIH) a viable alternative for replacing materials derived from non-renewable sources. However, there is a gap in research on functional OIH coatings, as there is no definitive answer regarding the structural characteristics of a hybrid material that make it effective in practical applications such as protective coatings against corrosion, UV rays, temperature, and abrasion. This project aims to initially characterize the structural properties of PU-silica (polyurethane-silica) OIH after applying different curing temperatures and to compare the results obtained with existing literature, seeking to establish the structural characteristics that enhance the protective properties of films against, for example, the corrosion of metal surfaces. Class II OIH will be synthesized, composed of glycerol- and sorbitol-based PU (two renewable monomers) functionalized with APTES ((3-aminopropyl)triethoxysilane) to enable the covalent bonding of the polymer with the silica network, produced from the hydrolysis and condensation of TEOS (tetraethyl orthosilicate). The structural characterization of the precursors and the OIH produced at different curing temperatures will utilize the following techniques: Fourier-transform infrared spectroscopy (FTIR), nuclear magnetic resonance (NMR) of 13C and 29Si, and small-angle X-ray scattering (SAXS). The challenge of this project lies in identifying these structural patterns that are consistent with data present in the literature.