Microcapsule-Type Self-Healing Protective Coating for Cementitious Composites with Secondary Crack Preventing Ability

Area of Science:

• Materials Science
• Polymer Chemistry
• Protective Coatings

Background:

• Developing self-healing materials is crucial for extending the lifespan of protective coatings.
• Existing coatings often lack the ability to prevent secondary damage after initial repair.

Purpose of the Study:

• To develop a microcapsule-based self-healing protective coating with enhanced crack prevention.
• To utilize a silanol-terminated polydimethylsiloxane (STP)/dibutyltin dilaurate (DD) healing system for coating repair.

Main Methods:

• Microcapsules containing STP and DD were synthesized using in-situ and interfacial polymerization.
• Characterization of microcapsules via FT-IR, optical microscopy, and SEM.
• Integration of microcapsules into enamel and epoxy formulations for application on various substrates.

Main Results:

• Successful demonstration of self-healing in scratched coatings using SEM, electrochemical, and water permeability tests.
• Confirmation of secondary crack prevention in the healed regions under vibration stress.
• Viscoelastic substance formation from STP and DD condensation reaction.

Conclusions:

• The developed dual-capsule self-healing coating effectively repairs damage and prevents secondary cracking.
• The STP/DD healing system shows promise for advanced protective coating applications.
• Microcapsule technology offers a viable route for creating durable and resilient materials.