Synthesis by fast thiol-Michael click addition of biodegradable and potentially fully biobased architectures based on starch and polyester, towards sustainable and performing multiphase systems.

For short-term sustainable applications such as packaging and agriculture, new biodegradable and renewable macromolecular architectures based on polysaccharide and polyester have been developed with an original multistep pathway, and then characterized. In a first step, amylomaize starch (AMS), based on rather linear polysaccharides with very high amylose content, and poly(butylene adipate-co-terephthalate) (PBAT), a potential fully biobased and biodegradable co-polyester, were chemically modified. Reactive maleimide and thiol groups have been added to their chemical structures. They have undergone a thiol-Michael addition, yielding a cross-linked network based on AMS and PBAT oligomers. In this large study, the structures of the different AMS and PBAT derivatives were precisely determined by FTIR, 1H, 13C APT and 31P NMR. Nitrogen containing products were also analyzed by 1H-15N NMR, a useful but largely underutilized tool, to determine the chemical structures of these synthesized products. This study clearly shows the high potential of these macromolecular architectures based on AMS and PBAT obtained by a fast click reaction, to develop reactive additives in the case of rather incompatible multiphase materials (blends, multilayers,) for a large range of short-term and demanding applications (packaging, agriculture,) for a greener future.