Controlled Latent Heat Phase-Change Microcapsules for Temperature Regulation
Chen Li1, Jijie Fu1, Fangsheng Huang1
1Department of Modern Mechanics, University of Science and Technology of China, Hefei, Anhui 230026, China.
ACS Applied Materials & Interfaces
|June 16, 2023
Summary
Highly controllable phase-change microcapsules (PCMCs) were developed using active flow focusing for precise temperature regulation. These microcapsules offer excellent thermal energy storage and management capabilities, improving energy efficiency.
Area of Science:
- Materials Science
- Chemical Engineering
- Energy Storage
Background:
- Microencapsulation of phase-change materials (PCMs) is crucial for enhancing energy efficiency and reducing carbon emissions.
- Developing precisely controlled microcapsules is key for effective thermal energy storage and management applications.
Purpose of the Study:
- To develop highly controllable phase-change microcapsules (PCMCs) using hexadecane core and polyurea shell for precise temperature regulation.
- To investigate the influence of fabrication parameters on PCMC size, shell thickness, and thermal properties.
Main Methods:
- Utilized a liquid-driven active flow focusing technique platform for microcapsule fabrication.
- Controlled microcapsule diameter via flow rate and excitation frequency, and shell thickness via monomer ratio.
- Characterized PCMCs for particle size uniformity, surface morphology, and thermal performance.
Main Results:
- Fabricated PCMCs with uniform particle size (CV < 2%), smooth surfaces, and compact structures.
- Demonstrated good phase-change performance, heat storage capacity, and thermal stability due to the polyurea shell.
- Observed distinct thermal property variations based on PCMC size and wall thickness.
Conclusions:
- The active flow focusing technique enables precise control over PCMC fabrication for tailored thermal properties.
- Developed hexadecane PCMCs show significant potential for applications in thermal energy storage and thermal management.
- The study validates the feasibility of these PCMCs for effective phase-change temperature regulation.
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