Gelation‐Free Synthesis of Hyperbranched Triphenylamine Polymer: Multifunctional Conjugated Electrochromic Polymers for Energy‐Storing and Heat‐Shielding Smart Windows

ABSTRACT Multifunctional electrochromic (EC) materials integrating optical modulation, energy storage, and thermal management are vital for next‐generation smart windows. Overcoming the challenge of achieving high transparency, structural precision, and redox stability in a single polymer, we report a gelation‐free hyperbranched conjugated poly(fluorene‐ alt ‐triphenylamine) ( P(Fl‐ alt ‐TPA) ) with a 100% degree of branching (DB). Synthesized via Suzuki–Miyaura polycondensation, it achieves high molecular weight without gelation, thereby overcoming the limitations of conventional A 2 + B 3 . An electrochromic supercapacitor based on this polymer exhibits high energy and power densities, successfully powering an LED and a timer for over 5 and 6 min, respectively. Remarkably, it maintains 80.6% capacity retention after 10 000 cycles. Furthermore, in device applications, it demonstrates pronounced NIR heat‐shielding (achieving a CR NIR of 91.9% and suppressing a water temperature rise by 60.7%) and distinct electrofluorochromism (with a contrast ratio of 177). These results highlight that precise engineering of high‐molecular‐weight hyperbranched conjugated polymers (CPs) without gelation effectively integrates transparency, electrochromism, energy storage, heat shielding, and fluorescence switching into a single platform for advanced smart windows and multifunctional optoelectrochemical applications.