Dynamic Graftable Liquid-Like Polymer Brush Coatings with Restorable Liquid Repellency

Area of Science:

• Materials Science
• Polymer Chemistry
• Surface Engineering

Background:

• Covalently grafted polymer brushes provide liquid repellency but are difficult to repair after abrasion.
• Existing liquid-repellent coatings lack durability and regenerative capabilities.

Purpose of the Study:

• To develop a novel supramolecular strategy for creating regenerable liquid-repellent coatings.
• To overcome the limitations of traditional polymer brush coatings in terms of repairability and durability.

Main Methods:

• Constructed a dense hydrogen-bonded matrix using 2-ureido-4[1H]-pyrimidinone (UPy) functionalized polyhedral oligomeric silsesquioxane (POSS).
• Inserted poly(dimethylsiloxane) with polar terminal groups (BHPDMS) via hydrogen bonding and dipole interactions at elevated temperatures.
• Characterized the coating's mechanical properties, optical transparency, and liquid-repellent performance.

Main Results:

• Achieved a covalent-analogous polymer brush coating with hardness of 0.34 GPa and modulus of 5.91 GPa.
• Demonstrated excellent liquid repellency with a water sliding angle of 1.8°, antismudge, and antigraffiti properties.
• Showcased significant reduction in ice adhesion (20.4 kPa) and extended freezing delay (>10-fold).
• Successfully regenerated the coating's liquid-repellent functionality after abrasion by reinserting BHPDMS.

Conclusions:

• Established a supramolecular design principle for durable and regenerable surface coatings.
• Reconciled covalent-analogous stability with regraftable adaptability for advanced surface engineering.
• Opened new avenues for sustainable and high-performance surface treatments.