Dual Anticorrosive and Self-healing Coating Based on Multiresponsive Polyaniline Porous Microspheres

Area of Science:

• Materials Science
• Corrosion Science
• Polymer Chemistry

Background:

• Developing advanced coatings with self-healing and long-term anticorrosion capabilities is crucial for extending material service life.
• Polyaniline (PANI) and benzotriazole (BTA) are known for their anticorrosive and responsive properties.
• Multiresponsive materials offer potential for smart coating applications.

Purpose of the Study:

• To develop a smart self-healing coating with enhanced long-term anticorrosion ability.
• To utilize multiresponsive polyaniline (PANI) porous microspheres loaded with benzotriazole (BTA).
• To investigate the pH-responsive, photoresponsive release, and photothermal conversion properties of the PANI microspheres.

Main Methods:

• Preparation of BTA-loaded PANI porous microspheres via emulsion template method and photopolymerization.
• Evaluation of anticorrosion performance using salt spray testing (700 h).
• Assessment of self-healing properties under near-infrared (NIR) light irradiation.

Main Results:

• The developed coating showed no corrosion after 700 h of salt spray testing, outperforming the blank coating (corrosion after 100 h).
• The composite coating demonstrated rapid self-healing within 5 s of NIR irradiation due to PANI's photothermal properties.
• BTA release from microspheres formed a passivation film, further repairing coating defects.

Conclusions:

• The BTA-loaded PANI microspheres provide dual anticorrosive properties and effective self-healing capabilities.
• The smart coating exhibits on-command responsive release, high healing efficiency, and excellent anticorrosion performance.
• This dual self-healing anticorrosion coating offers a promising approach for extending the service life of metals.