Summary:
Researchers in the Department of Materials Science and Engineering at UCLA have developed a thermally responsive transparent semicrystalline copolymer for smart windows.
Background:
Solar heat gain and heat loss from windows lead to significant increases in energy consumption. Current insulation techniques, such as double and triple-pane glass, have been widely adopted, but are not sufficient for energy optimization. As a result of poor temperature control from insulation issues, there is an increased demand for energy efficient window options. Smart windows are an attractive option that incorporate active materials that respond to external stimuli, such as heat or mechanical stress, which allows for dynamic control of light transmission. Specifically, thermally responsive smart windows allow for passive optical tuning and modulation of solar energy. Current smart windows utilize polymer-dispersed liquid crystals or hydrogels. However, both options involve liquid components that may lead to shorter shelf lives and potential leaks. Therefore, there is an unmet market need for an innovative polymer that remains transparent and can achieve solar modulation without the high cost and low durability that is seen with current state-of-the-art materials.
Innovation:
UCLA researchers in the department of materials science and engineering have developed an innovative thermo-responsive, phase-changing copolymer for smart window applications. This transparent, semicrystalline copolymer is composed of a majority highly crystalline co-monomer and a non-compatible minority co-monomer, forming a transparent copolymer that remains clear at elevated temperatures. This innovative copolymer has the ability to transition to a scattered state at elevated temperatures, subsequently mitigating solar heat gain in hot weathers. Furthermore, it has demonstrated a transmittance of 91.4% at 20C and a 3.7% at 50C, with proven durability over 1000 heating and cooling cycles. Furthermore, this copolymer has been shown to modulate incoming solar radiation, significantly reducing solar heat gain. With its superior performance in low temperature transmittance and solar modulation capabilities, this polymer could revolutionize smart window applications and energy saving solutions and potentially reduce electrical grid demands.
Demonstration Video:
Transparent Semicrystalline Copolymer for Smart Window Applications
Potential Applications:
• Thermally responsive smart windows
• Greenhouse windows
• Automotive and transportation industry
• Solar panels
• Smart glasses
• Aerospace and aviation
Advantages:
• Modulation of solar radiation
• Ability to change transparency with external stimuli
• Single composition
• Low cost
• Easy installation procedures
• Improved durability compared to previous solutions
• Environmental friendliness & efficiency
State of Development:
The inventors have successfully completed lab tests in which this hydrogel supported growth of dental pulp stem cells and their transformation into neuron-like and bone-forming cells.
Reference:
UCLA Case No. 2024-267
Relevant Papers:
1. Ying Liu, Jiacheng Fan, Roshan Plamthottam, Meng Gao, Zihang Peng, Yuan Meng, Mingfei He, Hanxiang Wu, Yufeng Wang, Tianxi Liu, Chao Zhang, and Qibing Pei. Chemistry of Materials 2021 33 (18), 7232-7241. DOI: 10.1021/acs.chemmater.1c01389
2. Y. Zhu, H. Wu, A. Martin, P. Beck, E. Allahyarov, T. Wongwirat, G. Rui, Y. Zhu, D. Hawthorne, J. Fan, J. Wu, S. Zhang, L. Zhu, S. Kaur, Q. Pei, Operando Investigation of the Molecular Origins of Dipole Switching in P(VDF-TrFE-CFE) Terpolymer for Large Adiabatic Temperature Change. Adv. Funct. Mater. 2024, 34, 2314705. https://doi.org/10.1002/adfm.202314705
Lead Inventor:
Qibing Pei, UCLA Professor of Materials Science and Engineering