Exploring robust microwave absorption properties of functional polyvinyl butyral (PVB) via facile cross-linking and data-driven material discovery

This work introduces a chemically facile approach for synthesizing cross-linked polyvinyl butyral (XPVB) at room temperature, utilizing divinyl sulfone (DVS) as the cross-linking agent. Leveraging data-driven discovery methods, we optimize the DVS concentration to enhance the material's reflection loss (RL) performance, establishing XPVB as a formidable contender in microwave absorption without the need for conventional filler materials. Gaussian Process Regression (GPR) was used in this analysis, the material's development process was streamlined to achieve a high-fidelity predictive model that closely aligns with the observed experimental data. The synergy between our GPR model and the empirical evidence is particularly noteworthy, with the GPR predictions exhibiting exceptional agreement across the investigated frequency range, especially in the Ku-band, where high RL values are crucial. These findings indicate that XPVB exhibits exceptional dielectric properties that translate into an unprecedented absorption bandwidth encompassing the entire Ku-band, paired with strong RL, thereby achieving a significant attenuation of electromagnetic waves even at minimal material thicknesses. The optimized XPVB sample, without any filler addition, delivers an exceptional RL performance. Notably, a 2.4 mm-thick XPVB sample demonstrated an extraordinary RL value of -44 dB with RL≤-10 dB absorption Ku-bandwidth (12.4–18 GHz), showcasing the material's potential as a standalone absorber. This synthesis methodology, combined with the analytical approach, lays the groundwork for further research and development in microwave absorbers and has the potential to significantly impact the fields of defense, telecommunications and self-powered devices by providing a new standard for material performance.