Self‐healing waterborne polyurethane coating by pH‐dependent triggered‐release mechanism

Abstract

In this study, effect of high‐loaded silica capsules with corrosion inhibitor on thermal degradation and self‐healing properties of waterborne polyurethane (WPU) was investigated. Silica capsules were synthesized using an oil in water (O/W) microemulsion and WPU was prepared via the prepolymer method. Assembled capsules demonstrated pH dependent release of their core. Incorporating silica capsule as an inorganic component resulted to improve thermal and barrier properties of WPU coatings. WPU coating with 1% silica capsules demonstrated better barrier quality in corrosive media and adding more than that resulted a rapid deterioration in barrier properties. Furthermore, such coatings possess an excellent adhesive strength with steel substrate. Electrochemical impedance spectroscopy was used in corrosion monitoring and healing procedure. Moreover, capsule morphology and thermal degradation of the WPU coating has been investigated separately by scanning electron microscopy and thermal gravimetric analysis. © 2018 Wiley Periodicals, Inc. J. Appl. Polym. Sci. 2019, 136, 47082.

High‐Performance UV Protective Waterborne Polymer Coatings Based on Hybrid Graphene/Carbon Nanotube Radicals Scavenging Filler

“…Innovation in waterborne polymer protective coatings is directed toward development of functional coatings by turning their action from passive protection toward active performance. As a result, wide range of functional coatings with high performance in self‐healing, anticorrosion, or UV protection has been developed. Protection against the UV irradiation especially for outdoor applications has shown to be one of the most important tools for development of long lasting coatings.…”

The influence of size and healing content on the performance of extrinsic self‐healing coatings

“…All of the samples containing silica capsules showed better adhesion properties compare to the pure WPU coating. 21 In the study of Mirmohseni et al, 21 a sample containing 2% silica capsules showed the highest adhesion to the steel substrate. The incorporation of silica capsules more than 2% to the WPU coating decreased the adhesion properties of coating to the substrate.…”

“…Smart coatings with the capability for self‐healing prolong the lifetime of metallic structures. In recent years, several strategies for self‐healing have been employed such as the release of healing agents, reversible bonds, and nanoparticles with the ability to migrate 19–23 . It has been proved that the release of the healing agent is the most well‐studied method among the other 24–26 .…”

“…In recent years, several strategies for self-healing have been employed such as the release of healing agents, reversible bonds, and nanoparticles with the ability to migrate. [19][20][21][22][23] It has been proved that the release of the healing agent is the most well-studied method among the other. [24][25][26] The release of the healing agent is an autonomic self-healing process based on the encapsulated active agents that is, catalysts, monomers, hardeners, and dyes.…”

In situ encapsulation technique for fabrication of self‐healing thermosetting polyurethane with tungsten (VI) chloride

“…Jadhav et al 25 produced microcapsules with their shells made of phenol–formaldehyde resin and their cores containing dryers, corrosion inhibitors, and linseed oil used in self‐healing, anticorrosion polyurethane coatings. Mirmohseni et al 26 studied the impact of inserting capsules filled with silica and corrosion inhibitors, on self‐healing properties and thermal corrosion of waterborne polyurethane (WPU). They made silica capsules by blending oil in water (O/W) microemulsion and the WPU through the employment of prepolymer method.…”