Covalent Adaptable Polymethacrylate Networks by Hydrazide Crosslinking Via Isosorbide Levulinate Side Groups.

Reversible crosslinking offers an attractive strategy to modify and improve the properties of polymer materials while concurrently enabling a pathway for chemical recycling. This can, for example, be achieved by incorporating a ketone functionality into the polymer structure to enable post-polymerization crosslinking with dihydrazides. The resulting covalent adaptable network contains acylhydrazone bonds cleavable under acidic conditions, thereby providing reversibility.

Poly(alkanoyl isosorbide methacrylate)s: From Amorphous to Semicrystalline and Liquid Crystalline Biobased Materials.

We have prepared a series of 12 d-isosorbide-2-alkanoate-5-methacrylate monomers as single regioisomers with different pendant linear C2-C20 alkanoyl chains using biocatalytic and chemical acylations. By conventional radical polymerization, these monomers provided high-molecular-weight biobased poly(alkanoyl isosorbide methacrylate)s (PAIMAs). Samples with C2-C12 alkanoyl chains were amorphous with glass transition temperatures from 107 to 54 °C, while C14-C20 chains provided semicrystalline materials with melting points up to 59 °C.

Hydroformylation of Olefinic Derivatives of Isosorbide and Isomannide.

The first time application of hydroformylation on olefinic derivatives of isosorbide and isomannide is shown by which a new carbon-carbon bond is formed. Depending on the ligand and reaction conditions used, the C6 regioisomer a can be obtained in 4:1 ratio and excellent yield, whereas C5 isomer b is achieved in almost complete regioselectivity (46:1) and good yield. In the majority of cases only the exo orientation is observed for the obtained aldehydes, and the method is easily applicable also on a 1 g scale.