Hybrid silica-chitin nano-composites through colloidal self-assembly – HYSIKIT

We recently described a new synthesis approach of hybrid nano-structured materials associating polysaccharide nanoparticles (chitin nanorods) with a silica matrix formed by siloxane oligomer condensation. We wish to pursue this research within the framework of the project HYSIKIT submitted to the Program Blanc of the ANR.

Organic-inorganic hybrid nano-structured materials are the subject of intensive research because of the new properties emerging from the intimate association at the nanometre scale of organic and inorganic constituents. In this context, where the search for more flexible and more thrifty ways of synthesis is a strong stake, we propose a method based on the self-assembly of colloids, which could represent an innovative conceptual approach. Besides, the project focuses on functionalised materials by studying the methods and elaboration processes allowing the modulation of the properties (composition, texture, morphology) at different length scales. Finally, it joins in a general context of research on new materials stemming from the biomass and alternative processes.

Our method combines the structuration of matter at the nanometre scale through “bottom-up” approaches and mechanisms inspired by biomineralisation and surfactant self-assembly processes. It consists in using supramolecular objects with calibrated dimensions as templates. We are seeking to exploit the particular self-assembling properties of colloids, by mastering as finely as possible the interactions between colloidal precursors. Having the ambition to develop a new family of processes and functional materials, we shall also consider the composite materials from the point of view of their mechanical properties, and porous materials of mixed oxides from the point of view of their performances in heterogeneous catalysis.

We shall develop this project over 4 years, with the following specific objectives: characterize hybrid chitin-silica colloids in suspension, study and manipulate the existing intermolecular interactions (task 2), elaborate in a controlled way hybrid biopolymer-oxide nano-composites with defined morphology using self-assembly of colloidal precursors (task 3) and finally, bring to light the remarkable properties resulting from nano-composite materials elaboration processes (tasks 4 and 5). The scientific program is organized so that the different tasks will enrich each other, while having specific objectives which can be reached or not, independently.

The project relies on a partnership (ICGM/Qualisud/IMP/CEMHTI) established around the carrier and initiator of the project (ICGM), by organizing a synergy based at the same time on an analogy of the systems (colloidal suspensions, nanomaterials, composites) and processes (auto-assembly, shaping, mineralization) studied in the framework of our respective research activities, and on complementary experimental approaches.