Biobased materials and fibres: exploiting the ingenuity of plant matter

We are making progress in our knowledge of the ability of plant material to become a source of new biopolymers or dedicated functions for an ever-increasing number of agro-materials.

In line with societal concerns linked to agro-ecological change and the bio-economy, particularly as regards plant production, the PVPP team is carrying out fundamental and applied research with non-food industries dealing with the quality of raw materials with a view to producing bio-based materials and composites. Our main materials of interest are derived from flax and hemp, but also from various co-products of plant production (wood and similar materials, more exotic lignocelluloses, etc.). The life cycle is a major component of our work. Lignocelluloses are assemblies of technologically recalcitrant polymers. They are composed mainly of cellulose and non-cellulosic polysaccharides (hemicelluloses, pectins) in addition to lignins. Lignocelluloses are thought to constitute the main dry matter fraction of terrestrial bioresources. This evidence seems to have been rediscovered two decades ago, in the light of the increasing scarcity of fossil fuels, environmental pollution crises and the need for systems to be sustainable. In addition to the agro-materials sector, lignocelluloses are now a credible resource in terms of volume, economy and performance, as a substitute for fossil resources in the production of bio-based molecules or assemblies.

In response to the strategic plans of the TRANSFORM department and the Institute, we have opened up two avenues of research:

• understanding and measuring the impact of global warming on the quality of lignocellulosic plant production (phenotyping) and helping producers to select more suitable lines (AGRAPI Industrial Chair) that are still suitable for processing (ANR Floeme). In particular, we are studying the effect of the rise in temperatures predicted by climatologists and the increase in drought episodes on the composition and structure of walls (EU FLOWER project), which leads to changes in the content and/or structure of polymers, modifying their interactions and properties.

• developing advanced composites (e.g. hygromorphic), capable of changing shape (ANR Redisegned4D) or of producing energy under environmental stimulation, or as substitutes for widely-used petro-sourced products (e.g. market garden clips, vine staples, etc. - FEDER SOLUSERRE projects). The design of new eco-materials from renewable organic sources, such as flax, raises the question of their ageing and durability over time. To answer this question, we are studying ancient agro-materials (hundreds or even thousands of years old!) to understand how the ageing of materials impacts the bio-polymers and structures (ANR ANUBIS project) that make up the plant walls.