Superspreading-Based Fabrication of Poly(methyl methacrylate) Films with High Toughness for Ultra-Wideband Flexible Transparent Antenna

With the rapid advancement of Internet of Things (IoT) technology, ultra-wideband flexible transparent antennas have garnered substantial attention for their potential applications in wireless communication devices. Poly(methyl methacrylate) (PMMA), renowned for its exceptional optical properties and favorable processing characteristics, has been extensively utilized as a transparent substrate material for antennas. However, the intrinsic brittleness of transparent PMMA substrates poses a significant limitation in applications such as flexible antennas. In this study, we introduce a superspreading strategy to address the complex trade-off among transparency, toughness, and dielectric properties in flexible electronics through molecular disorder engineering. The PMMA films fabricated via this superspreading strategy exhibit a visible transmittance of 85-95% at 400 nm, a toughness of 9 × 10⁵ J/m³ (representing an enhancement of 150-225% compared to conventional methods), and a frequency-stable permittivity (ε_r = 3.6 ± 0.05) within the 9-12 GHz range. These films also feature a precisely tunable thickness range of 5.5-60 μm. The PMMA-based flexible transparent antenna demonstrates a gain of 2-4 dBi and a relative bandwidth of 40%, thereby confirming its suitability for ultra-wideband applications. Collectively, this research presents a promising candidate for the development of ultra-wideband flexible transparent antennas.