Organocatalysis is an important branch of catalysis for various organic transformations and materials preparation. Polymerizations promoted by organic catalysts can produce polymeric materials without any metallic residues, providing charming materials for high-value and sensitive domains such as biomedical applications, microelectronic devices and food packaging. Herein, we describe a fluorinated alcohol based catalytic system for polypeptide synthesis via catalytic ring-opening polymerization (ROP) of α -amino acid N -carboxyanhydride (NCA), fulfilling cocatalyst free, metal free, high rate and high selectivity. During polymerization, the fluorinated alcohol catalyst forms multiple dynamic hydrogen bonds with the initiator, monomer and propagating polymer chain. These cooperative hydrogen bonding interactions activate the NCA monomers and simultaneously protect the overactive initiator/propagating polymer chain-ends, which offers the whole polymerization with high activity and selectivity. Mechanistic studies indicate a monocomponent-multifunctional catalytic mode of fluorinated alcohol. This finding provides a metal free and fast approach to access well-defined polypeptides.

Vitrimer, the third category of polymer materials, combines the properties of traditional thermosets and thermoplastics and has gained much interest from industry since the first report in 2011. Currently, many researchers focus on the exploration of new chemistry for novel vitrimer synthesis but pay less attention to the fabrication of vitrimer composites based on known vitrimer systems. The latter can not only largely decrease the cost of vitrimers but also provide a facile way to increase the variety of vitrimer-based materials and extend the applications of vitrimers in different fields. In this study, we developed a new class of vitrimer composite using polycarbonate as a matrix and natural cellulose paper as the reinforcing framework for the first time. The resultant materials possess exceptional mechanical properties and great thermal/chemical stability, simultaneously exhibiting a series of smart properties, such as shape-memory, reshaping, self-healing, and reprocessing. Noteworthily, the two main components of the resultant materials, polycarbonate and natural cellulose, can be easily recycled under mild conditions; thus, these new vitrimer composites qualify as novel green and sustainable materials.

Organic luminogens have extensive applications due to their unique photophysical properties. In recent years, nonconjugated organic luminogens, in contrast to traditional conjugated luminogens, have gained much attention because of their facile preparation, environmental friendliness, and biocompatibility. In this study, a new kind of nonconventional luminogen based on dynamic covalent cross-linked polyhydroxyurethane is reported for the first time. The new luminogen not only exhibits intrinsic strong fluorescent emission in the solid state but also possesses high mechanical properties along with good shape memory and self-healing properties. In addition, the new luminogens are synthesized from aliphatic polyfunctional cyclic carbonate and amines via a much more straightforward method, avoiding the use of toxic isocyanates. Investigations indicated that the intrinsic luminescence of the resultant luminogens was induced by the cross-linking of polymer chains and could be well tuned by controlling the degree of cross-linking. By taking advantage of the unique characteristics of the resultant polymer luminogens, we further developed a facile method, named "light-mediated ink-free screen printing", for anticounterfeiting paper fabrication. Different from traditional ink-based printing technology, the new method used UV-light instead of expensive security ink to encode anticounterfeiting information on natural cellulose paper. The anticounterfeiting information is stable under various wet conditions, showing promising applications in the fast-growing counterfeiting of pharmaceuticals, packaging, and the food industry.

Functionalized polypeptides have attracted tremendous interest in recent years and found many stimulating applications owing to their tunable physicochemical characteristics including hydrophilicity and stimuli‐responsive behavior. The development of new strategies to produce these polymers without metallic contaminants is crucial for their applications in high‐value and sensitive domains, such as biomedical, microelectronic, food‐packaging, and personal beauty care fields. Herein, a highly efficient strategy to access well‐defined site‐specific functionalized polypeptides is developed by combining Michael reaction with hydrogen‐bonding organocatalytic ROP of NCA. A library of chain‐end and chain‐middle functionalized polypeptides (14 examples) with predesigned molecular weights and low polydispersities are readily prepared with this approach. Specifically, the whole synthetic process is metal‐free, fulfilling high activity and selectivity at room temperature.

Functionalized polypeptides have attracted tremendous interest in recent years and found many stimulating applications owing to their tunable physicochemical characteristics including hydrophilicity and stimuli‐responsive behavior. The development of new strategies to produce these polymers without metallic contaminants is crucial for their applications in high‐value and sensitive domains, such as biomedical, microelectronic, food‐packaging, and personal beauty care fields. Herein, a highly efficient strategy to access well‐defined site‐specific functionalized polypeptides is developed by combining Michael reaction with hydrogen‐bonding organocatalytic ROP of NCA. A library of chain‐end and chain‐middle functionalized polypeptides (14 examples) with predesigned molecular weights and low polydispersities are readily prepared with this approach. Specifically, the whole synthetic process is metal‐free, fulfilling high activity and selectivity at room temperature.