The evolution of material design has mirrored advancements in the understanding of materials, nature, and the requirements of target applications. Originally, materials were only intended to play a passive role, but with a deepened understanding of material properties and design has come an improved ability to harness these properties to create materials with predetermined response mechanisms. This article has three aims: i) to briefly discuss the origin of and motivation for having materials that are capable of undergoing healing either extrinsically or intrinsically; ii) to present the most recent and promising advancements in the field of self‐healing materials; and iii) to discuss important material design and property specifications that should be considered in order to promote the development of optimized self‐healing materials.

Cyclodextrins belong to the most important and promising macrocyclic hosts, since they are inexpensive, water-soluble natural products, non-toxic, readily functionalized and commercially available. Cyclodextrin chemistry creates lots of research areas. The present review focuses on investigations of cyclodextrins in polymer chemistry and their applications in drug delivery systems. Click reactions as a possibility to obtain polymer chains with covalently attached cyclodextrins are described, and examples for the application of such polymers in drug delivery are shown.

Poly(3,4‐ethylenedioxythiophene):poly(styrenesulfonate) (PEDOT:PSS) has been is applied as hole transport material in organic electronic devices for more than 20 years. However, the redundant sulfonic acid group of PEDOT:PSS has often been overlooked. Herein, PEDOT:PSS‐DA is prepared via a facile doping of PEDOT:PSS with dopamine hydrochloride (DA·HCl) which reacts with the redundant sulfonic acid of PSS. The PEDOT:PSS‐DA film exhibits enhanced work function and conductivity compared to those of PEDOT:PSS. PEDOT:PSS‐DA‐based devices show a power conversion efficiency of 16.55% which is the highest in organic solar cells (OSCs) with (poly[(2,6‐(4,8‐bis(5‐(2‐ethylhexyl)‐4‐fluorothiophen‐2‐yl)benzo[1,2‐b:4,5‐b′]dithio‐phene))‐co‐(1,3‐di(5‐thiophene‐2‐yl)‐5,7‐bis(2‐ethylhexyl)‐benzo[1,2‐c:4,5‐c′]dithiophene‐4,8‐dione))] (PM6):(2,2′‐((2Z,2′Z)‐((12,13‐bis(2‐ethylhexyl)‐3,9‐diundecyl‐12,13‐dihydro‐[1,2,5]thiadiazolo[3,4‐e]thieno[2′′,3′:4′,5′]thieno[2′,3′:4,5]pyrrolo[3,2‐g]thieno[2′,3′:4,5]thieno[3,2‐b]indole‐2,10‐diyl)bis(methanylylidene))bis(5,6‐difluoro‐3‐oxo‐2,3‐dihydro‐1H‐indene‐2,1‐diylidene))dimalononitrile) (Y6) as the active layer. Furthermore, PEDOT:PSS‐DA also exhibits enhanced performance in three other donor/acceptor systems, exhibiting high compatibility in OSCs. This work demonstrates that doping PEDOT:PSS with various amino derivatives is a potentially efficient strategy to enhance the performance of PEDOT:PSS in organic electronic devices.

Block copolymers containing metal centers and related segmented architectures are attracting attention as a class of materials with properties and functions that complement those of their all-organic analogues. These materials phase-separate into nanoscopic, metal-rich domains either in bulk or in thin films and form core–shell nanoparticles in selective solvents. Moreover, the linkages binding the metal centers can be varied from covalent bonds that lead to “static” bonding through to noncovalent, kinetically labile, or “dynamic” interactions, which affords remarkable flexibility in terms of materials design. In this Perspective we provide an overview of recent progress and future challenges in terms of applications in nanopatterning and sensing, and as stimuli-responsive and self-healing materials.

Highly efficient planar heterojunction perovskite solar cells (PVSCs) with dopamine (DA) semiquinone radical modified poly(3,4-ethylenedioxythiophene) polystyrene sulfonate (PEDOT:PSS) (DA-PEDOT:PSS) as a hole transporting layer (HTL) were fabricated. A combination of characterization techniques were employed to investigate the effects of DA doping on the electron donating capability of DA-PEDOT:PSS, perovskite film quality and charge recombination kinetics in the solar cells. Our study shows that DA doping endows the DA-PEDOT:PSS-modified PVSCs with a higher radical content and greater perovskite to HTL charge extraction capability. In addition, the DA doping also improves work function of the HTL, increases perovskite film crystallinity, and the amino and hydroxyl groups in DA can interact with the undercoordinated Pb atoms on the perovskite crystal, reducing charge-recombination rate and increasing charge-extraction efficiency. Therefore, the DA-PEDOT:PSS-modified solar cells outperform those based on PEDOT:PSS, increasing open-circuit voltage (V oc ) and power conversion efficiency (PCE) to 1.08 V and 18.5%, respectively. Even more importantly, the efficiency of the unencapsulated DA-PEDOT:PSS-based PVSCs are well retained with only 20% PCE loss after exposure to air for 250 hours. These in-depth insights into structure and performance provide clear and novel guidelines for the design of effective HTLs to facilitate the practical application of inverted planar heterojunction PVSCs.

We report on the synthesis of poly(l-lysine-b-caprolactone) block copolymers via an original and elegant approach whereby Z-l-lysine is first polymerized in the presence of allylamine and the resulting amino-terminated poly(Z-l-lysine) is then used in situ as macroinitiator for the polymerization of ε-caprolactone in the presence of tin(II) octanoate as catalyst. A range of poly(ester-b-peptide)s were obtained by varying the ratio of polypeptide to polycaprolactone units. After removal of the Z group of l-lysine units, the copolymers were soluble in water and their solution behavior was examined. They spontaneously form micelle-like objects in solution with sizes around 10 and 70 nm depending on the block lengths of the hydrophilic and hydrophobic sequences. The smaller size particles would adopt a core−shell morphology while the larger particles would be more in line with a vesicle morphology.

Elastic bicomponent networks with shape memory effect were obtained via cross-linking reactions of unsaturated polyester with methacrylates. Unlike conventional shape memory polymers, the new material is transparent, rubbery, and can be tailored to various transition temperatures by macromolecular engineering. Various unsaturated copolymers of R-methylene-γ-butyrolactone and ε-caprolactone were synthesized by ring-opening mechanism. Depending on the composition of the unsaturated polyester materials, their mechanical properties and glass transition temperature were varied.

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