Emmanuel Lacôte, Univ Lyon, University Claude Bernard Lyon 1, CNRS, CNES, ArianeGroup, LHCEP

I am a CNRS researcher in the hydrazines and polynitrogen energy derivatives laboratory. A radical chemist by training, I am interested in the chemistry of the main block, applied in particular to polymer chemistry.

With the group of Jacques Lalevée in Mulhouse we developed NHC-borane derivatives that can initiate radical photopolymerization using visible light, then with the help of Elodie Bourgeat-Lami and Muriel Lansalot, from the CP2M laboratory, we extended the use of our borated initiators in polymerizations in dispersed media.

The visible photopolymerization of resins with our initiators led to networks with better mechanical properties than those obtained from the same resins but with other initiators. We therefore made a request for solid NMR time to Infranalytics to characterize the environment of boron in the networks.

The spectra produced showed unambiguously that the boron atoms participated in the crosslinking of the networks via the growth of several polymer chains from the same atoms (up to 3 arms). It is this additional crosslinking which, added to that brought about by the bifunctional monomers, is at the origin of the best properties. Without the skills and sensitivity of Infranalytics spectrometers, it would not have been possible to have this detailed understanding of bond states.

For more info: https://onlinelibrary.wiley.com/doi/10.1002/anie.202103008 

Platform used: CRMN Lyon