High-performance polymers (HPPs) play an important role in modern technology. Many efforts aim to develop cost-effective pathways to synthesize polymers without causing any harm to health and the environment. Polyimides (PIs) belong to the class of HPPs and they show outstanding features e.g. high-tempera­ture stability, resistance to aggressive chemicals and radiation, as well as insulating properties. PI synthesis, however, present yet major challenges. We herein present an alternative approach to PIs of intriguing shape and of impressive size.

Organic colorants are an important type of compounds mainly characterized by the presence of conjugated moieties and color-generating functions (chromophores), such as carbonyl, azo or nitroso functions. They find various applications in coloring all kinds of substances – from plastics to clothes – but are unfortunately often synthesized by toxic and environmentally harmful routes. This review first explains the physicochemical basis of colorants, then gives an introduction to their classifications and general syntheses and ends with a highlight of recent advances in the environmentally friendly hydrothermal synthesis of colorants.

High-performance polymers (HPPs) play an important role in modern technology. Many efforts aim to develop cost-effective pathways to synthesize polymers without causing any harm to health and the environment. Polyimides (PIs) belong to the class of HPPs and they show outstanding features e.g. high-tempera­ture stability, resistance to aggressive chemicals and radiation, as well as insulating properties. PI synthesis, however, present yet major challenges. We herein present an alternative approach to PIs of intriguing shape and of impressive size.

Organic colorants are an important type of compounds mainly characterized by the presence of conjugated moieties and color-generating functions (chromophores), such as carbonyl, azo or nitroso functions. They find various applications in coloring all kinds of substances – from plastics to clothes – but are unfortunately often synthesized by toxic and environmentally harmful routes. This review first explains the physicochemical basis of colorants, then gives an introduction to their classifications and general syntheses and ends with a highlight of recent advances in the environmentally friendly hydrothermal synthesis of colorants.

High-performance polymers (HPPs) play an important role in modern technology. Many efforts aim to develop cost-effective pathways to synthesize polymers without causing any harm to health and the environment. Polyimides (PIs) belong to the class of HPPs and they show outstanding features e.g. high-tempera­ture stability, resistance to aggressive chemicals and radiation, as well as insulating properties. PI synthesis, however, present yet major challenges. We herein present an alternative approach to PIs of intriguing shape and of impressive size.

Organic colorants are an important type of compounds mainly characterized by the presence of conjugated moieties and color-generating functions (chromophores), such as carbonyl, azo or nitroso functions. They find various applications in coloring all kinds of substances – from plastics to clothes – but are unfortunately often synthesized by toxic and environmentally harmful routes. This review first explains the physicochemical basis of colorants, then gives an introduction to their classifications and general syntheses and ends with a highlight of recent advances in the environmentally friendly hydrothermal synthesis of colorants.