Polyurethane graphene nanocomposites with self-healing properties by azide-alkyne click reaction
By Akhan, Seda; Oktay, Burcu; Özdemir, Oğuz Kaan; Madakbaş, Seyfullah; Apohan, Nilhan [Kayaman
Published in Materials Chemistry and Physics
2020
Abstract
Nanocomposites stand out as promising materials in many fields due to their properties such as strength, hardness, thermal stability, and lightness. Introducing self-healing ability to polymer nanocomposites provides new guidelines for strong, sustainable, and durable materials. Microcapsule-based self-healing materials work independently of an external stimulus such as pH, heat, light and solvent. In this paper, we developed autonomously self-healing UV-cured polyurethane graphene oxide nanocomposite coatings by means of efficient and useful copper-catalyzed azide-alkyne (CuAAC) click chemistry. Low molecular weight tetra-arm azide was successfully capsulated within poly(vinyl formal) capsules. Alkyne functional graphene-oxide reinforced nanocomposites containing azide microcapsules were prepared through photo-polymerization. The self-healing ability and anti-corrosion properties of the nanocomposites were studied after the damage occurred. The self-healing experiments show that the microcapsules provided a self-healing efficiency of around 70% after 24 h. Chemical, morphologic, mechanical, and thermal properties of the films were investigated. Furthermore, the electrochemical analysis of films showed that the microcapsule containing films has a higher polarization resistance and a lower corrosion current.