A one pot one step combined radical and ring-opening route for the dual functionalization of starch in aqueous medium

Julie Meimoun (1) , Vincent Wiatz (2) , René Saint-Loup (2) , Julien Parcq (2) , Adélina David (3) , Grégory Stoclet (3) , Valérie Gaucher (3) , Audrey Favrelle-Huret (1) , Fanny Bonnet (3) , Philippe Zinck (1)

1 UCCS - Unité de Catalyse et Chimie du Solide - UMR 8181
2 Roquette Frères
3 UMET - Unité Matériaux et Transformations - UMR 8207

Starch based materials are attractive bio-based alternative to fully synthetic polymers. Native starch has however limited thermoprocessability and properties and must be modified. In order to improve the properties of starch-graft-poly(butyl-acrylate-co-styrene) copolymers via a process as green as possible, we report herein a new method for the dual functionalization of the polysaccharide via a one pot one step reaction in aqueous medium combining free radical polymerizations and ring-opening chemistry. Poly(butyl acrylate) / poly(butyl acrylate-co-styrene) (ca. 60 000 g/mol) and oligo(-caprolactone) were grafted on starch with a grafting percentage up to 75 %. The copolymers show two glass transition temperatures: one around 55-60°C related to starch and a second attributed to the grafted vinyl polymers, from-46°C to 20°C depending on butyl acrylate/styrene ratio). The resulting dual functionalized materials exhibit excellent mechanical properties, with elongation at break in the range 20-210 %, while single functionalized starch shows less than 5 %.

Mots clés: starch; graft copolymerization; structural / thermomechanical properties

Domaines: Catalyse

Julie Meimoun, Vincent Wiatz, René Saint-Loup, Julien Parcq, Adélina David, et al.. A one pot one step combined radical and ring-opening route for the dual functionalization of starch in aqueous medium. Carbohydrate Polymers, 2021, Carbohydrate Polymers, pp.117399. ⟨10.1016/j.carbpol.2020.117399⟩. ⟨hal-03017282⟩