Use of a hydrosilylation reaction for the preparation of structure-controlled boroxine-based polyborosiloxanes

• Published in: Reactive & functional polymers 2024-12, Vol.205, p.106094, Article 106094
• Main Authors: Manokhina, Elizaveta A., Tukhvatshin, Rinat S., Khanin, Dmitriy A., Frank, Inga V., Vasil'ev, Viktor G., Anisimov, Anton A.
• Format: Article
• Language: English
• Subjects: Boroxine; Cross-linking agent; Hydrosilylation reaction; Polyborosiloxane; Siloxane
• ISSN: 1381-5148
• DOI: 10.1016/j.reactfunctpolym.2024.106094

The structure of organosilicon vinyl-containing boroxine was confirmed by 1H nuclear magnetic resonance (NMR) spectroscopy, infrared (IR) spectroscopy and matrix-assisted laser desorption/ionization (MALDI) mass spectrometry. Its thermal properties were studied using thermogravimetric analysis (TGA) and differential scanning calorimetry (DSC) methods. The ability of boroxine to undergo hydrosilylation using the Karstedt's catalyst was investigated on various organosilicon substrates. Boroxine was shown to be involved in these reactions as a cross-linking agent. The formation of dynamic boroxine cross-links allowed the analysis of the reaction products by NMR spectroscopy, including the use of polyfunctional hydride-containing reagents. In all cases the addition proceeds selectively to the β-position and with complete conversion. The structure of the resulting polyborosiloxane containing 1.4 mol% of modified units was also confirmed by 1H NMR spectroscopy, and its thermal and rheological properties were studied. [Display omitted] •The structure of organosilicon vinyl-containing boroxine was confirmed.•The reactivity of the boroxine in hydrosilylation reactions was investigated.•The addition proceeds selectively to the β-position and with complete conversion.•The simple synthesis provides an access to structure-controlled polyborosiloxanes.