Chiral nanostructures of isosorbide- and isomannide-based polyurethanes

Sustainable cycloaliphatic polyurethanes: from synthesis to applications

Polyurethanes (PUs) are a versatile and major polymer family, mainly produced via polyaddition between polyols and polyisocyanates. A large variety of fossil-based building blocks is commonly used to develop a wide range of macromolecular architectures with specific properties. Due to environmental concerns, legislation, rarefaction of some petrol fractions and price fluctuation, sustainable feedstocks are attracting significant attention, e.g., plastic waste and biobased resources from biomass. Consequently, various sustainable building blocks are available to develop new renewable macromolecular architectures such as aromatics, linear aliphatics and cycloaliphatics. Meanwhile, the relationship between the chemical structures of these building blocks and properties of the final PUs can be determined. For instance, aromatic building blocks are remarkable to endow materials with rigidity, hydrophobicity, fire resistance, chemical and thermal stability, whereas acyclic aliphatics endow them with oxidation and UV light resistance, flexibility and transparency. Cycloaliphatics are very interesting as they combine most of the advantages of linear aliphatic and aromatic compounds. This original and unique review presents a comprehensive overview of the synthesis of sustainable cycloaliphatic PUs using various renewable products such as biobased terpenes, carbohydrates, fatty acids and cholesterol and/or plastic waste. Herein, we summarize the chemical modification of the main sustainable cycloaliphatic feedstocks, synthesis of PUs using these building blocks and their corresponding properties and subsequently present their major applications in hot-topic fields, including building, transportation, packaging and biomedicine.

Design of primary amine-functionalized polymer containing chiral isosorbide in the main chain for the asymmetric synthesis of isoquinuclidine derivatives

A novel isosorbide containing primary amine-functionalized chiral polymer was synthesized and used as the catalyst for the asymmetric synthesis of isoquinuclidines.

Fabrication of a chiral luminescent hydrogel from gold nanoclusters via molecular recognition

A novel supramolecular chiral hydrogel with enhanced emission was obtained by the co-assembly of achiral thiobarbituric acid-modified gold nanoclusters (TBA-AuNCs) with chiral histidine molecules. Chirality transfer from histidine to the supramolecular hydrogels was achieved through the π-π stacking and intermolecular H-bonding based on molecular recognition. This work gives a creative strategy for the building of chiral nanocluster-based materials.