Elsevier

Applied Surface Science

Volumes 467–468, 15 February 2019, Pages 912-925
Applied Surface Science

Full Length Article
Influence of silsesquioxane addition on polyurethane-based protective coatings for bronze surfaces

https://doi.org/10.1016/j.apsusc.2018.10.217Get rights and content
Under a Creative Commons license
open access

Highlights

  • Solvent-born polyurethane-based protective coatings for bronze were developed.

  • Influence of POSS on mechanical properties and protection efficiency was studied.

  • Hardness, elastic modulus were not influenced, but abrasion resistance was improved.

  • Ex situ IR RA confirmed the benevolent influence of POSS on protection efficiency.

  • Dielectric constants and coating resistivities reflect positive influence of POSS.

Abstract

Two-component solvent-born polyurethane coatings for the protection of bronze from corrosion were prepared. Trisilanol-heptaisooctyl polyhedral oligomeric silsesquixane (POSS) nanoparticles were exploited to increase the coating protective efficiency. Its improvement was confirmed through a combination of characterisation techniques. In particular, the POSS addition caused an increase of the water contact angle, and an enhancement of the elastic connotation and abrasion resistance of the polyurethane coating. Potentiodynamic polarisation measurements also indicated that the coating containing POSS nanoparticles has an improved protection efficiency. Impedance spectroscopy revealed that the magnitude of low-frequency impedance of polyurethane coatings decreased more for the coating without POSS during exposure in electrolyte for thirty days. Ex situ IR reflection-absorption spectroelectrochemistry was exploited to get insight into the degradation of coatings during chronocoulometric charging at anodic potentials. IR reflection-absorption technique was also used to evaluate any possible effect of different stripper solutions on the bronze substrate.

Keywords

Bronze
Polyurethane
Protective coating
POSS
Impedance
Infrared spectroscopy

Cited by (0)