abstract
Waterborne polymer coatings have the potential to address the environmental concerns associated with solvent based systems. To improve their performance without using volatile organic compounds, we propose a new approach based on reconfigurable covalent crosslinking that provides mechanical resistance and self-healing properties. The new waterborne polymer coatings are based on mixtures of aldehyde- and aminefunctionalized polymer nanoparticles (PNPs) that take advantage of the reversibility of imine bonds in the presence of water. Different degrees of functional monomer incorporation (10 % to 40 %) allowed us to balance crosslinking and interdiffusion during film formation, to obtain mechanically robust and solvent resistant films. A clear structure-properties relation was assessed by following the formation of water resulting from aminealdehyde condensation crosslinking, measured by differential scanning calorimetry. The resulting polymer coatings further show self-healing properties at room temperature, triggered with residual amounts of water and featuring high recovery rates of the mechanical properties. Our mechanically robust waterborne polymer coatings based in imine reversible crosslinking, featuring self-healing in mild conditions, offer excellent prospects for application in smart coating materials.
keywords
LATEX-PARTICLES; FILM FORMATION; COPOLYMERIZATION; NETWORKS; EMULSION; INTERDIFFUSION; METHACRYLATE); NANOPARTICLES; CHEMISTRY; DIFFUSION
subject category
Chemistry; Materials Science
authors
Martins, TD; Viciosa, MT; Oliveira, MB; Fernandes, A; Mano, JF; Baleiza, C; Farina, JPS
our authors
João Mano
Vice Director
Mariana Braga de Oliveira
Assistant Researcheracknowledgements
The authors acknowledge the financial support of Fundacao para a Ciencia e a Tecnologia (FCT), projects PTDC/CTM-COM/1581/2021, UIDB/00100/2020, UIDP/00100/2020 and LA/P/0056/2020, and PhD grant SFRH/BD/132486/2017 (T. D. Martins). We thank Prof. Madalena Dionisio for the use of the DSC equipment.