Polyacrylate resins containing fluoroalkyl groups for powder clear coatings

This work focuses on the synthesis of polyacrylate resins containing fluoroalkyl groups, which are used to prepare powder clear coatings. The resin synthesis was carried out using 2-hydroxyethyl methacrylate (HEMA), methyl methacrylate (MMA), n-butyl acrylate (BA), 2-phenoxyethyl acrylate (PhEA) as well as two acrylate monomers containing fluoroalkyl groups, i.e. 2,2,2-trifluoroethyl methacrylate (TFEMA) and 2,2,2-trifluoroethyl acrylate (TFEA). The presence of fluorine in the resin was confirmed by 19F NMR spectroscopy, while at the coating surface by polarized optical microscopy equipped with a laser elemental analyzer. Gel permeation chromatography (GPC) was used to determine the average molecular mass and molecular mass distribution of the synthesized resins. Additionally, the viscosity measurement of the resins was performed using a Brookfield viscometer. The thermal behavior of the powder coatings was investigated using differential scanning calorimetry (DSC). Moreover, FT-IR spectra were performed to confirm the crosslinking reaction between hydroxyl groups of the resin and polyisocyanate curing agent. The properties of the cured coatings were tested, such as: roughness, gloss, adhesion to the steel surface, hardness, cupping, scratch resistance and water contact angle. The obtained coatings were characterized by good properties: gloss, adhesion to the steel surface, scratch resistance, and hydrophobicity.