Efficient Iodine Uptake of Ultra Thermally Stable Conjugated Copolymers Bearing Biaceanthrylenyl Moieties and Contorted Aromatic Units Using a [3 + 2] Palladium-Catalyzed Cyclopolymerization Reaction

A novel series of copolymers made from alternating aromatic surrogates with contorted and spiro compounds, denoted as <b>BCP1–3</b>, was successfully synthesized employing a palladium-catalyzed one-pot [3 + 2] cyclopentannulation reaction. The resulting copolymers <b>BCP1–3</b>, which were isolated in high yields, exhibited weight-average molecular weights (<i>M</i>_w) ranging from 11.0 to 61.5 kg mol^–1 (kDa) and polydispersity index (<i>M</i>_w/<i>M</i>_n) values in the range of 1.7 and 2.0, which suggest a narrow molecular weight distribution, thus indicating the formation of uniform copolymer chains. Investigation of the thermal properties of <b>BCP1–3</b> by thermogravimetric analysis disclosed outstanding stability with 10% weight loss temperature values reaching 800 °C. Iodine adsorption tests revealed remarkable results, particularly for <b>BCP2</b>, which demonstrated a strong affinity toward iodine reaching an uptake of 2900 mg g^–1. Additionally, recyclability tests showcased the effective regeneration of <b>BCP2</b> after several successive iodine adsorption–desorption cycles.