TY - JOUR

T1 - Iridium-polysiloxane hybrid: catalyst retention and enhanced thermal performance in cross-linked silicone materials

AU - Filippova, Sofia S.

AU - Белобородов, Андрей Александрович

AU - Дерябин, Константин Валерьевич

AU - Колесников, Илья Евгеньевич

AU - Кукушкин, Вадим Юрьевич

AU - Исламова, Регина Маратовна

PY - 2026/2/1

Y1 - 2026/2/1

N2 - This study presents the first synthesis of a dual-functional iridium-containing polysiloxane hybrid, Ir-BipyP(DMS-co-MVS), that simultaneously serves as both catalyst and vinyl-containing reagent in cross-linking reactions. The structure of the polymer metal complex has been characterized by 1H, 13C{1H}, 29Si{1H} NMR and the molecular weight has been determined using GPC analysis. The synthesized Ir-BipyP(DMS-co-MVS) demonstrates redox activity (E1/2 = 0.94 V (IrIII/IrIV couple) and E1/2 = −1.09 V (Bipy•−/Bipy)), orange luminescence (λem = 610 nm, QY = 7.8 %) and excellent compatibility with commercial polysiloxanes. Swelling measurements confirmed effective cross-linking with poly(methylhydrosiloxane) (PMHS) via hydrosilylation reaction. The covalent incorporation of iridium sites into the polymer network eliminates catalyst leaching — a persistent problem with conventional low molecular weight catalysts — while maintaining high catalytic activity. The resulting silicone rubber, Ir-BipyP(DMS-co-MVS)/PMHS, exhibits exceptional thermal stability with T5% values of 400 °C (air) and 520 °C (argon), representing improvements of conventional silicone rubbers. This research addresses the fundamental challenges in silicone processing, while opening new possibilities for high-temperature applications in thermal protection systems, coatings, sealants and electronics.

AB - This study presents the first synthesis of a dual-functional iridium-containing polysiloxane hybrid, Ir-BipyP(DMS-co-MVS), that simultaneously serves as both catalyst and vinyl-containing reagent in cross-linking reactions. The structure of the polymer metal complex has been characterized by 1H, 13C{1H}, 29Si{1H} NMR and the molecular weight has been determined using GPC analysis. The synthesized Ir-BipyP(DMS-co-MVS) demonstrates redox activity (E1/2 = 0.94 V (IrIII/IrIV couple) and E1/2 = −1.09 V (Bipy•−/Bipy)), orange luminescence (λem = 610 nm, QY = 7.8 %) and excellent compatibility with commercial polysiloxanes. Swelling measurements confirmed effective cross-linking with poly(methylhydrosiloxane) (PMHS) via hydrosilylation reaction. The covalent incorporation of iridium sites into the polymer network eliminates catalyst leaching — a persistent problem with conventional low molecular weight catalysts — while maintaining high catalytic activity. The resulting silicone rubber, Ir-BipyP(DMS-co-MVS)/PMHS, exhibits exceptional thermal stability with T5% values of 400 °C (air) and 520 °C (argon), representing improvements of conventional silicone rubbers. This research addresses the fundamental challenges in silicone processing, while opening new possibilities for high-temperature applications in thermal protection systems, coatings, sealants and electronics.

KW - Cross-linking

KW - Iridium(III) complex

KW - Macrocatalyst

KW - Polysiloxane

KW - Thermal stability

UR - https://www.mendeley.com/catalogue/77f47e36-612d-3a3b-8874-383d5d22b047/

U2 - 10.1016/j.inoche.2025.116010

DO - 10.1016/j.inoche.2025.116010

M3 - Article

VL - 184

JO - Inorganic Chemistry Communication

JF - Inorganic Chemistry Communication

SN - 1387-7003

M1 - 116010

ER -