ED Sciences Chimiques
Design of non-isocyanate polyurethanes (NIPU)s through transfer reactions and complementary reactions
by Nichollas JAQUES (Laboratoire de Chimie des Polymères Organiques)
The defense will take place at 9h30 - Amphi 1 16 Avenue Pey-Berland 33607 Pessac Cedex
in front of the jury composed of
- Henri CRAMAIL - Professeur des universités - Université de Bordeaux - Directeur de these
- Michael MEIER - Professor - Karlsruhe Institute of Technology (KIT) - Directeur de these
- Haritz SARDON - Professor - University of the Basque Country - UPV/EHU - Examinateur
- Katrien BERNAERTS - Associate Professor - Maastricht University - Examinateur
- Patrick THEATO - Professor - Karlsruhe Institute of Technology (KIT) - Examinateur
- Étienne GRAU - Assistant professor - Université de Bordeaux - Examinateur
- Fanny BONNET - Directrice de recherche - CNRS - Rapporteur
- Fabrice BUREL - Professor - INSA Rouen Normandie - Rapporteur
Polyurethanes (PUs) are versatile materials. However, these polymers are traditionally synthesized from toxic isocyanates, raising regulatory concerns. This thesis investigates two greener strategies for non-isocyanate polyurethane (NIPU) polymerization: (1) transurethanization of carbamates with diols and (2) radical-initiated thiol-ene. The transurethanization approach was optimized through catalyst selection, monomer ratio control, and mechanical stirring, achieving high-molar-mass NIPUs (Mn up to 105 kg×mol) with tunable thermal (Tg from −68 °C to 128 °C) and mechanical properties (Young's Modulus = 20 to 1200 MPa). These materials mechanical behavior ranged from soft elastomers to rigid thermoplastics and were applied successfully as thermoplastic hot-melt adhesives (HMAs). The adhesive performance was influenced by the polarity, crystallinity, and hydrogen bonding. The thiol-ene strategy enabled the synthesis of sulfur-rich NIPU without urea byproducts, showing enhanced thermal stability, flexibility and adhesion, in comparison to traditional systems. A reactive bonding setting further improved lap shear strength beyond conventional HMAs. All these strategies demonstrate the potential for sustainable NIPUs suitable for adhesives and elastomer applications and offering safer alternatives to isocyanate-based polyurethanes.