How Researchers are Engineering Flexible and Wearable Electronics with Thermal Analysis

From foldable smartphones to wearable health monitors, the electronics industry is demanding materials that are not only conductive but also flexible, durable, and thermally stable. Designers and manufacturers are challenged to optimize processing and ensure finished products can withstand operating conditions without failure – and doing so requires multiple types of thermal analysis.

Thermal analysis supports flexible electronics development by characterizing key material properties such as:

• Thermal stability and degradation, including phase transitions and temperature limits
• Thermomechanical properties: behavior under thermal and mechanical stress, including stretching and dimensional stability
• Viscoelasticity: time-dependent deformation, important for flexibility

Together, these insights enable engineers to fine‑tune formulations, predict long‑term reliability, and design materials that maintain performance even under repeated bending and thermal changes. The following examples highlight recent research using TA Instruments’ thermal analysis instrumentation to push the boundaries of electronic material design.

New flexible electronics (such as foldable screens or wearable health monitors) require polymer coatings that can maintain strong adhesion to metal substrates under repeated mechanical stress and thermal cycling. Conventional polyimides suffer from poor interfacial adhesion, so researchers Guo et. al. used thermal analysis to molecularly engineer a new benzoheterocycle-based copolyimide (BIBOPI) backbone that offers enhanced substrate adhesion and flexibility without sacrificing thermal stability.¹

Feng Guo et. al. recognized that thermal stability “is an essential property, as it determines the upper limit of the material’s operational temperature” and many conventional soft-pack battery protective layers fail to satisfy the requirements of high-performance applications such as “aerospace, medical devices, industrial equipment, and high-load energy storage applications.” Therefore, they designed BIBOPI with excellent thermal stability, with the glass transition temperatures exceeding 300 °C. This materials engineering strategy directly addresses industry demands for durable, lightweight and highly reliable flexible packaging technologies.

Their thermal analysis suite included:

• Discovery TGA 550 to study thermal stability and degradation behavior, which are critical for high-performance packaging.
• Discovery DSC 250 provided the glass transition temperatures (T_g) and insights into subtle transitions which helped confirm chain mobility.
• DMA on RSA-G2 provided high-sensitivity viscoelastic data which helped better understand rigidity versus flexibility.
• TMA Q400 supported static thermodynamic analysis as well as providing CTE and dimensional stability for substrate compatibility.

Similarly, Kulkarni et. al. set out to characterize a new non-silicone-based thermoset polymeric substrate that can withstand stretching and varying deformation rates in foldable electronics applications.² Their tests characterized thermal properties, phase transitions, thermomechanical properties through isothermal tensile loading, and viscoelasticity. This work supports the reliable deployment of Beyolex™ in devices that undergo repeated deformation across wide temperature ranges.

Their thermal analysis suite included:

• Discovery DSC 25 to test thermal stability across operational range (25 °C to 150 °C).
• TGA on an SDT Q600 measured percentage mass loss and thermal degradation, validating safe use up to high temperatures for foldable electronics.
• DMA Q800 measured viscoelastic properties, isothermal monotonic and cyclic tensile tests. These tests revealed mild temperature sensitivity and rate-dependent behavior for long-term reliability modeling.

Wearable temperature sensors are reshaping medical and personal thermal management applications, but “often face challenges in achieving accuracy, flexibility and multifunctionality.”³ Researchers Hongxu Guo et. al. developed a biodegradable polymer-based quaternary composite with self-regulating heating and temperature sensing capabilities. The composite offers precise thermal self-regulation and stable power consumption, as well as excellent recyclability, making it ideal for electronic skins.

Their thermal analysis methods included:

• DMA Q800 offered insights from CTE and viscoelastic response of the material systems to achieve reliable self-regulating performance.
• DSC Q200 helped identify crystallinity changes from melting transitions and latent heat of the material systems – critical for tuning thermal response.

Han et. al. strove for even higher sustainability with their conductive liquid metal-vitrimer composite that enables recyclable and reconfigurable electronics.⁴ Their design enhances recyclability and versatility while also improving thermal conductivity and maintaining high stretchability and thermal stability.

Their thermal analysis tests included using:

• DSC 2500 offered insights into phase transitions and confirmed that LM inclusions did not interfere with vitrimer network formation.
• TGA Q500 highlighted how improved heat transfer from fillers affected the onset and progression of degradation within the composite.
• DMA Q800 revealed the viscoelastic response and demonstrated that the composites maintained flexibility and self- healing characteristics under deformation.
• Fox 50 highlighted the enhancement in thermal conductivity of the incorporated material’s heat-dissipation capability.

As the above research demonstrates, key breakthroughs and material verification in wearable and flexible electronics are enabled by TA Instruments’ leading thermal analyzers. Researchers seeking to completely characterize their materials combine multiple thermal techniques, which is made easy with TRIOS software’s compatibility across all thermal instrumentation for simple data overlays. From thermal stability and degradation to viscoelasticity and key transitions, thermal analysis is critical to the success of these next-generation electronics. Researchers rely on TA Instruments’ technical expertise and support as the leader in thermal analysis for over 50 years.

References

• Guo, Feng, Wei Wang, Guangtao Qian, Dandan Li, and Yongfeng Li. 2025. “Tailoring Substrate Adhesion Via Flexible Chain Architecture Design in Benzoheterocycle Polyimide Protective Coatings.” RSC Advances 15 (2025): 39540–53. https://doi.org/10.1039/d5ra05693d.
• Kulkarni, Siddhesh S., Israr Ud Din, Yarjan Abdul Samad, and Kamran A. Khan. 2025. “Thermo-Viscoelastic Characterization and Modeling of a High-Temperature Stretchable Film for Foldable Electronics Applications.” International Journal of Engineering Science 216 (2025): 104352. https://doi.org/10.1016/j.ijengsci.2025.104352.
• Guo, Hongxu, Lichang Lu, Kairen Zhao, Huaiyu Yang, Helen Willcock, Elisa Mele, Xujin Bao, Eileen Yu, Han Zhang, and Yi Liu. 2026. “Recyclable Near-Body Temperature Eutectic System with Double Positive Temperature Coefficient Effect for Personalised Thermal Regulation.” Materials Horizons 13 (2025): 1517–31. https://doi.org/10.1039/d5mh01491c.
• Han, Youngshang, Sargun Singh Rohewal, Sumit Gupta, Shreya Paul, Christopher C. Bowland, and Mohammad H. Malakooti. 2025. “Conductive Liquid Metal Vitrimer Composites for Reconfigurable and Recyclable Flexible Electronics.” Advanced Functional Materials 35 (2025). https://doi.org/10.1002/adfm.202511119.