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Preparation and Performance Study of n-Undecane Phase Change Cold Storage Material
Luchao Yan1, Yang Wang1, Shijian Lu1
1College of Material Science and Engineering, Nanjing Tech University, Nanjing 211816, China.
Materials (Basel, Switzerland)
|April 13, 2024
Summary
New microcapsules using n-undecane and PMMA offer efficient cold storage solutions. Optimized n-undecane/PMMA microcapsules provide superior thermal performance for energy-saving cold chain logistics.
Area of Science:
- Materials Science
- Chemical Engineering
- Thermodynamics
Background:
- Traditional refrigeration methods in cold chain logistics are energy-intensive.
- Developing novel energy storage materials is crucial for energy saving and emission reduction.
- National standards require frozen logistics temperatures below -18 °C.
Purpose of the Study:
- To develop and optimize microencapsulated phase change materials (MEPCM) for cold storage applications.
- To investigate the impact of emulsifiers, core-shell ratio, and emulsification rate on MEPCM performance.
- To evaluate the thermal properties and micro-surface morphology of n-undecane/PMMA microcapsules.
Main Methods:
- Suspension polymerization was used to prepare n-undecane/PMMA microcapsules.
- Characterization techniques included SEM, DSC, FTIR, and laser particle size analysis.
- Systematic variation of emulsifiers (SMA, Tween-80, Tween-80/span-80), SMA dosage, core-shell ratio, and emulsification speed.
Main Results:
- SMA emulsifier yielded superior thermal performance and micro-surface morphology with a complete core-shell structure.
- Optimal conditions (7% SMA, 2.5:1 core-shell ratio, 2000 rpm) resulted in the highest enthalpy of phase change (120.3 kJ/kg).
- The MEPCM demonstrated good thermal stability and cycle life, with enthalpy decreasing by only 18.6 kJ/kg after 200 cycles.
Conclusions:
- Optimized n-undecane/PMMA microcapsules are effective phase change materials for cold storage.
- These microcapsules offer favorable microstructure, uniform particle size, and efficient energy storage capabilities.
- The developed MEPCM presents a promising solution for the refrigeration and freezing sectors, aligning with energy-saving goals.
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