Thermal-driven cellulose-based hydrogels with reversible phase transition for smart optical regulation

Area of Science:

• Materials Science
• Smart Materials
• Polymer Chemistry

Background:

• Solar radiation significantly increases building and vehicle interior temperatures, posing safety risks.
• Effective solar regulation is crucial for thermal management and energy efficiency.

Purpose of the Study:

• To develop a novel hydrogel system for adaptive solar regulation.
• To investigate the relationship between hydrogel composition and phase transition temperature.
• To explore the material's potential for passive cooling and smart device applications.

Main Methods:

• Development of a hydroxypropyl cellulose-based hydrogel.
• Machine learning feature screening to identify key compositional factors for phase transition.
• Incorporation of polyacrylamide (PAM) and CaCl2 to enhance mechanical properties and responsiveness.
• Testing of solar modulation capabilities and indoor temperature reduction.

Main Results:

• The hydrogel exhibits reversible optical switching between opaque and transparent states.
• Machine learning guided the optimization of the hydrogel for thermal regulation in hot climates.
• The material effectively reduced solar power transmission and indoor temperatures.
• Enhanced mechanical strength and multi-responsiveness (temperature, humidity, stress) were achieved.

Conclusions:

• The developed hydrogel is a promising material for adaptive solar regulation and passive cooling.
• Its tunable properties enable applications in smart windows, optical encryption, and interactive interfaces.
• The study demonstrates a pathway for designing advanced thermal-responsive materials.