[They chose France series #5] Sergei Kostjuk joins the Paris Institute of Molecular Chemistry

Could you tell us a little about your background and research topics?

I received my Ph.D. degree in polymer chemistry in 2002 from the Belarusian State University. I stayed in this university for most of my career: after creating my own laboratory focused on catalysis of polymerization processes at the Research Institute for Physical Chemical Problems in 2008, I became Associate Professor in 2012. I also headed the chair of high molecular weight compounds at the Chemistry department in 2018. Finally, I was promoted as Professor in 2021.

From the start of my Ph.D. and during my 25-year career, I have kept a focus on cationic polymerization, a chain growth process in which active species are positively charged. One of my biggest projects at the Belarusian State University involved the design of a new catalytic system for the synthesis of so-called highly reactive polyisobutylene, a key intermediate for preparation of ashless additives to motor oil and fuel. I conducted this project in cooperation with BASF, a major chemical company, which awarded our team a substantial funding of 400 k€ over the years. This collaboration resulted in more than 20 publications and more than 15 joint patents. Unfortunately, we had to discontinue the project in 2022 due to the Russian aggression against Ukraine. I hope to start this partnership over now that I have a new position in France.

Besides cationic polymerization, my research interests encompass polymer synthesis, catalysis, and green chemistry. Recently, I have taken on photoinitiated polymerization, organic electronics and stimuli-responsive polymers as well.

What motivated your application to the CNRS?

While working at the Belarusian State University, I paid multiple visits to French laboratories as part of individual and ANR [French National Research Agency] projects, as well as industrial contracts. I mainly collaborated with colleagues at the Institut Charles Gerhardt1  in Montpellier between 2006 and 2011, then at the Ingénierie des matériaux polymères2  in Lyon between 2014 and 2017.

I learnt about CNRS during those numerous visits to France. I realized that working at CNRS opened great opportunities. It would allow me to perform my own research program and to contribute to the solution of important fundamental scientific problems. As I had previously worked with many CNRS researchers, such as François Ganachaud, I was confident in my ability to create a research network around the country.

During the application process, I selected the Paris Institute of Molecular Chemistry for two main reasons. When I met the Polymer Chemistry team in 2023, I realized that my skills strongly matched the laboratory’s research program. I could well imagine developing new and more sustainable approaches toward the preparation of (co)polymers with my future colleagues. The second reason is the laboratory has included in the past some renowned scientists in my field, such as Pierre Sigwalt – who actually founded the laboratory that would become IPCM’s polymer chemistry team in the 1950s – and Jean-Pierre Vairon. After they left, the laboratory unfortunately stopped its activities on cationic polymerization. I am really looking forward to reviving investigations on this topic!

What differences have you noticed between your previous work environment and the one you are discovering here?

Unfortunately, we have very few good scientists and research groups in my home country. Therefore, possibilities to work with Belarusian colleagues are scarce. In contrast, the scientists I work with at my new laboratory in France have an extensive multidisciplinary experience in polymer synthesis. Their expertise opens exciting opportunities to discover new mechanisms and create new materials. This network does not stop at the laboratory: we can cooperate with other research groups in France and abroad.

The IPCM is also well equipped with state-of-the-art instruments and analytical platforms. In short, our work environment is much more competitive. And the icing on the cake, if I may add: the number of vacation days for CNRS personnel!

Do you still have ongoing projects with Belarus?

Although several of my projects are still running in my former laboratory at the Belarusian State University, I am not leading them anymore. That being said, I still consult with my former co-workers and I will keep working on some research topics I initiated in Belarus at my new laboratory. I am grateful for the support I received both from CNRS (a 150 k€ grant) and Sorbonne Université (a financial support for one PhD student), which will help me attracting the best scientists from my former laboratory to carry out my research on cationic polymerization in France.

Due to the international turmoil with Russia and Ukraine, working with Belarusian State University seems to be complicated today. I hope that the collaboration will become possible again at a better time. Belarus is home to many talented young researchers, who would benefit from an integration in the European scientific community.

What are your prospects for the coming years?

My scientific project focuses on the elaboration of metal-free catalytic systems for precision synthesis of functional (co)polymers via cationic polymerization from both petroleum-based and bio-based monomers. The goal is to meet the requirements of a circular economy, thus minimizing the negative impact on the environment. Something else I would like to achieve with this project is the synthesis of new materials by combination of cationic polymerization with other techniques (ATRP, RAFT, ROP). There are many applications for this, such as organic electronics and medicine. In the long-term, I would like to develop efficient approaches toward recycling, depolymerization to monomers or transformation to valuable chemicals of (co)polymers prepared via a cationic mechanism.

Editor: CD

• 1CNRS/ENSC Montpellier/Université de Montpellier
• 2CNRS/INSA de Lyon/Université Claude Bernard Lyon 1/Université Jean Monnet