The straightforward synthesis of a urea polymer network is presented. Commercially available monomers are polymerized using light-induced polymerization, resulting in networks crosslinked by hindered urea molecules. These moieties are reversible and, thus, can be converted into the starting compounds (that is, isocyanate and amine) by a simple thermal treatment. This process is monitored using differential scanning calorimetry as well as Raman and infrared spectroscopy. Furthermore, the self-healing ability of these polymer networks is investigated using scratch-healing tests as well as bulk-healing investigations using tensile testing. The resultant materials have a high E-modulus, are able to heal scratches at temperatures above 70°C multiple times and their mechanical properties can be partially regenerated. The underlying healing mechanism is based on the reversible opening of the urea bonds and exchange reactions between two functional groups, which were confirmed from a spectroscopic analysis. In summary, these new materials are a new type of intrinsically healable polymers and provide a first step toward hard and healable polymers.

In this work, we present a new strategy to engineer novel self-healing ionomers, namely, zwitterionic polymers, and a comprehensive analysis of their mechanical, viscoelastic, and scratch-healing properties. This new method enables reproducible damage of the polymer surfaces, calculation of the scratch volume through tactile profile scans, and quantification of the self-healing efficiency. Based on the results of the scratch tests and complementary rheology, differential scanning calorimetry (DSC), thermogravimetric analysis (TGA) and hardness tests, new trends, and structure-property relationships can be identified.

Poly(lauryl methacrylate)s with anthracene moieties in the side chain were converted with C60‐fullerene and phenyl‐C61‐butyric acid methyl ester (PCBM), resulting in new remendable (self‐healing) polymeric materials. The utilization of differently substituted anthracene monomers enabled the tuning of the reactivity and the resulting mechanical properties. Copolymers with different contents of the anthracene moieties were synthesized and characterized using size exclusion chromatography, 1H nuclear magnetic resonance (NMR) spectroscopy as well as differential scanning calorimetry (DSC). 1H NMR spectroscopic studies were utilized in order to investigate the reversibility of the Diels–Alder reaction between copolymers with C60‐fullerene and PCBM, respectively, in solution. In order to investigate the conversion of the polymers with C60‐fullerene and PCBM in bulk, additionally, DSC, nanoindentation, rheology, atomic force microscopy (AFM), 3D microscopy, simultaneous thermal analysis (STA) and FT‐Raman investigations were performed. The fullerene‐containing copolymers could be healed in a temperature range of 40–80 °C. Consequently, a new generation of low temperature remendable polymers could be established. © 2017 Wiley Periodicals, Inc. J. Appl. Polym. Sci. 2018, 135, 45916.

The incorporation of reversible covalent bonds into polymeric materials offers the possibility to generate polymers with self‐healing ability. For this purpose, three new oxime crosslinkers are synthesized and crosslinked by the copolymerization with different commercially available methacrylates via a photo‐polymerization process. These crosslinked materials are investigated regarding a potential self‐healing behavior. Moreover, the influence of different additives (polymerizable acids, photo acids, and acid developers) to enable self‐healing is studied in detail. Thereby, the limit of self‐healing based on reversible covalent bonds is reached in these materials. Due to the high stability of the oxime bonds in bulk materials no exchange reactions as well as no self‐healing behavior could be observed. © 2016 Wiley Periodicals, Inc. J. Appl. Polym. Sci. 2016, 133, 44168.

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The synthesis of novel platinum-based metallopolymers for self-healing applications is presented. For this purpose, terpyridine-platinum complexes were studied using isothermal titration calorimetry regarding their complexation behavior with pyridine. The obtained knowledge was utilized for the preparation of metallopolymers using the reversible addition fragmentation chaintransfer -polymerization technique resulting in well-defined polymers. Crosslinking with a tetravalent pyridine-crosslinker enabled the synthesis of a metallopolymer network featuring self-healing properties. From these experiments, more information about the molecular preconditions for the design of healable metal-containing polymers could be drawn enabling a further optimization of these systems in the future.

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For this paper, the self-healing ability of poly(methacrylate)s crosslinked via reversible urea bonds was studied in detail. In this context, the effects of healing time and temperature on the healing process were investigated. Furthermore, the impact of the size of the damage (i.e., area of the scratch) was monitored. Aging processes, counteracting the self-healing process, result in a decrease in the mechanical performance. This effect diminishes the healing ability. Consequently, the current study is a first approach towards a detailed analysis of self-healing polymers regarding the influencing parameters of the healing process, considering also possible aging processes for thermo-reversible polymer networks.