Plastics : Self-Healing Plastic

Self-healing plastic is a type of advanced material that can repair damage to itself without external intervention, restoring its structure and functionality after being scratched, cracked, or broken.

In-depth explanation:

Self-healing plastics contain special components that activate when damage occurs. 

These materials work through various mechanisms:

Microencapsulation: 

Tiny capsules containing healing agents are embedded throughout the plastic. 

When damage occurs, these capsules break open, releasing the healing agent that flows into the damaged area and solidifies.

Reversible chemical bonds: 

Some self-healing plastics use reversible chemical bonds that can break and reform when exposed to stimuli like heat, light, or pressure.

Shape memory:

Certain polymers remember their original shape and can return to it when heated.

Supramolecular chemistry: 

Materials designed with weak bonds that can reform after being broken.

Examples:

Commercial applications:

• Phone screen protectors that repair minor scratches throughout the day
• Automotive paint that can heal small scratches when exposed to sunlight
• Electronic device coatings that prevent water damage by sealing breaches

Research examples:

• Feist Healable Network Polymers: Can repair deep cuts when exposed to light
• University of Illinois system: Uses a vascular network similar to blood vessels to deliver healing agents

Stanford university materials: 

Self-healing electronics that can restore conductivity after being cut in half

Everyday products:

• Nissan's scratch shield paint: car paint that heals minor scratches
• LG G flex phones: featured a self-healing back cover
• Gibbs' self-healing cutting boards: kitchen cutting boards that seal knife marks

The field is rapidly evolving, with researchers working to make these materials more efficient, more durable, and capable of healing larger damages with less external stimulus needed.