Dr. Mathilde LAIRD

- ABSTRACT -

Perfectly defined oligomeric silsesquioxanes:
fundamental studies and use as building blocks for material chemistry

Oligomeric silsesquioxanes are a class of organo-silicon compounds with the formula (RSiO_3/2)_n,  with n being the number of silicon atom and R an organic group (e.g. chloropropyl, vinyl, phenyl, etc.).^[1] This family includes the cages silsesquioxanes (also referred to as polyhedral oligomeric silsesquioxanes, POSS) with the most common being the T₈ cage made of 8 Si-atoms. These hybrid molecules have been widely used by the polymer scientists as an inorganic load to increase the mechanical and thermal properties while avoiding phase segregation. However, they have also attracted attention for catalysis, luminescence and coating applications due to their hybrid nature, high concentration of organic groups, etc.^[1]

In this talk, we will explore the preparation, identification and characterization of different types of oligomeric silsesquioxanes. Less common cage silsesquioxanes including T₁₀, T₁₂ and T₁₈ cages containing respectively 10, 12 and 18 Si-atoms as well as fluoride encapsulating T₈ (T₈-F) cages have been prepared and studied.^[2,3] The design of Janus T₄ tetrapods, structures made of a 4 Si-atoms ring displaying 2 different types of functional groups on each face of the ring will also be discussed.^[4]

Oligomeric silsesquioxanes can be used as building block for material synthesis and have been integrated to bulk sol-gel-based material. Perspectives about the possibility to use those oligomers for well-defined modification of surface material for detection in biological media will be presented.

References
[1]    D. B. Cordes, P. D. Lickiss, F. Rataboul, Chem. Rev. 2010, 110, 2081–2173.
[2]    M. Laird, N. Herrmann, N. Ramsahye, C. Totée, C. Carcel, M. Unno, J. R. Bartlett, M. Wong Chi Man, Angew. Chemie Int. Ed. 2021, 60, 3022–3027.
[3]    M. Laird, C. Totée, P. Gaveau, G. Silly, A. Van der Lee, C. Carcel, M. Unno, J. R. Bartlett, M. Wong Chi Man, Dalt. Trans. 2021, 50, 81–89.
[4]    M. Laird, C. Carcel, M. Unno, J. R. Bartlett, M. Wong Chi Man, Molecules, 2022, 27, 7680.

Date de l'évènement : mardi 27 mai
Heure : 10h30
Lieu : salle de conférences de l'ISM (3e étage)
Contacts : Mathilde LAIRD & Conférences ISM