Comparison of the protective efficiency of polymethacrylates with different side chain length for AA2024 alloy

Journal of Materials Research and Technology

Marcos Flores¹  Mamié Sancy²  Marcela Urzúa³  Maria V. Encinas⁴  Paulo Molina⁵  Maritza A. Páez⁵  Camila Arcos⁶  Lisa Muñoz⁶  Tamara Bruna⁶  Carolina Guerra⁷  Hugo Muñoz⁸ 

[1] Centro de Investigación en Nanotecnología Materiales Avanzados CIEN UC, Pontificia Universidad Católica de Chile, Vicuña Mackenna 4860, Macul, Santiago, Chile;Corresponding author.;Departamento de Ingeniería Mecánica y Metalúrgica, Facultad de Ingeniería, Pontificia Universidad Católica de Chile, Vicuña Mackenna 4860, Macul, Santiago, Chile;Centro de Investigación Austral Biotech, Universidad Santo Tomas. Avenida Ejército 146, Santiago, 8320000, Chile;Departamento de Ingeniería Mecánica y Metalúrgica, Facultad de Ingeniería, Pontificia Universidad Católica de Chile, Vicuña Mackenna 4860, Macul, Santiago, Chile;Departamento de Química de los Materiales, Facultad de Química y Biología, Universidad de Santiago de Chile, Av. L. B. O'Higgins 3363, Casilla 40, Correo, 33, Santiago, Chile;Escuela de Construcción Civil, Facultad de Ingeniería, Pontificia Universidad Católica de Chile, Vicuña Mackenna 4860, Macul, Santiago, Chile;Laboratory of Surface and Nanomaterials, Physics Department, Faculty of Physics and Mathematics Science, Universidad de Chile, Beauchef 850, Santiago, 8370415, Chile;

关键词: Poly(methyl methacrylate);    Poly(butyl methacrylate);    Poly(hexyl methacrylate);    Corrosion;    Protection;    Coating;   

DOI  :  

来源: DOAJ

【 摘 要 】

The protective properties of polymethacrylate coatings with different side chain lengths for 2024 aluminum alloys were studied, focusing on the chain length increase but also on the Ar-plasma pretreatment applied to the metal surface. The coatings were obtained by photopolymerization, obtaining reproducible molecular weight polymers during each process that were determined by high-performance liquid chromatography. AA2024 alloy were immersed into the polymethacrylate solution using methyl, butyl, and hexyl as monomers. Their roughness was then evaluated using atomic force microscopy. Surface hydrophobicity and contact angle hysteresis were analyzed in water and diiodomethane. Protective properties were evaluated by electrochemical impedance spectroscopy after 56 days of immersion in a 0.1 M Na2SO4. The alloy cross-sections were examined by field emission scanning electron microscopy and glow discharge optical emission spectroscopy, allowing the estimation of film thickness. Surface analysis revealed that the defect population densities in the coatings increased the monomer alkyl chain length. The immersion thickness increase was consistent with contact angle measurements taken over time, and independent from the chain length. Contradicting expectations, the results showed the protective efficacy was not related to the chain length, since after exposure, the PBMA film revealed the best anti-corrosive coating performance on the AA2024. This was possibly influenced by its polymeric film conformation, hydrophilicity, ordering and lower density of defects on the metal surface.

【 授权许可】

Unknown