Chemical fixation of the greenhouse gas carbon dioxide with diepoxides followed by melt-phase polyaddition of the resulting difunctional cyclic carbonates with 1,12diaminododecane (DDA) yields semicrystalline polyhydroxurethane (PHU) thermoplastics. Also, 100% biobased semicrystalline PHU thermoplastics are feasible. Opposite to conventional polyurethane syntheses, neither isocyanates nor phosgene are required as intermediates. Preferably, melt-phase polyaddition is performed in a twin-screw compounder in the absence of catalysts, which also catalyze side-reactions. Calorimetric measurements and small-angle X-ray scattering reveal the fundamental structure−property relationships governing PHU crystallization. The PHU melting temperatures vary between 40 and 115 °C, and PHU Young's moduli range from 220 to 1430 MPa. Moreover, non-isocyanate PHU thermoplastic elastomers (TPHE) are readily tailored via melt-phase polyaddition of diamine-terminated flexible PHU prepolymers serving as soft segments combined with semicrystalline PHU as hard segments. As verified by means of thermal analysis (DSC), dynamic mechanical analysis (DMA), X-ray diffraction (SAXS), and microscopy (AFM), the careful balance between soft and semicrystalline hard-segment incorporation accounts for nanophaseseparation, which in the past has failed as a result of phase intermixing resulting from strong hydrogen bonding between soft and hard segments. For the first time, tailored PHU thermoplastics are employed in extrusion-based additive manufacturing by means of fused deposition modeling (FDM) or fused filament fabrication (FFF). Clearly, the presence of hydroxyl groups and their hydrogen bonding improves filament fusion and adhesion essential for achieving mechanical properties similar to PHU melt extrusion without encountering warpage.

Polymer templates are a facile way to control the formation, size, and shape of different inorganic nanomaterials by tuning solution behavior, morphology, or density and the type of functional groups. As a novel class of such templates, we herein introduce polyampholytic graft copolymers, more specifically, poly(dehydroalanine)-graft-poly-(ethylene glycol) (PDha-g-PEG), which feature a polyampholytic backbone with varying net charge and charge densities at different pH values and PEG grafts, providing molecular solubility over the entire pH range. As the PDha backbone features both amino and carboxylic acid groups in each repeat unit, selective interaction with [AuCl 4 ]and Ag + salts is possible, and this permits a straightforward synthesis of Ag, Au, and AgAu alloy nanoparticles. In this regard, we used different approaches: light-induced, thermal, and chemical reduction. As a unique feature, PDha-g-PEG enables control over AgAu nanoalloy composition via the pH value, as this directly affects the charge ratio (−NH 3 + /−COO − ) along the polymeric backbone. The obtained hybrid materials were investigated with respect to structure, shape, composition, and optical properties of nanoparticles via transmission electron microscopy, X-ray photoelectron spectroscopy, energy-dispersive X-ray spectroscopy, thermogravimetric analysis, and UV−vis spectroscopy. In our opinion, this is a facile way to control nanoalloy composition and this can be extended to other mono-or bimetallic nanoparticle examples.

We herein introduce a versatile platform of graft copolymers featuring a polyampholytic backbone and side chains of varying length and polarity using post-polymerization modification of polydehydroalanine (PDha).

In this work, we present an ew synthetics trategy for fourfold-substituted perylene monoimides via tetrabrominated perylene monoanhydrides. X-ray diffraction analysis unveiled the intramolecular stacking orientation between the substituents and semicircular packing behavior.W eo bserved the remarkable influence of the substituent on the longevity and nature of the excited state upon visible light excitation.I nt he presenceo fp oly(dehydroalanine)-graftpoly(ethylene glycol)g raft copolymers as solubilizing template, the chromophores are capable of sensitizing [Mo 3 S 13 ] 2À clustersi na queous solution for stable visible light driven hydrogen evolution over three days.

Three triggers result in two measurable outputs from polymeric sensors: multiresponsive polyampholytic graft copolymers respond to pH‐value and temperature, as well as the type and concentration of metal cations and therefore, allow the transformation of external triggers into simply measurable outputs (cloud point temperature (TCP) and surface plasmon resonance (SPR) of encapsulated silver nanoparticles). The synthesis relies on poly(dehydroalanine) (PDha) as the reactive backbone and gives straightforward access to materials with tunable composition and output. In particular, a rather high sensitivity toward the presence of Cu2+, Co2+, and Pb2+ metal cations is found.

To obtain a set of polycaprolactones (PCL) with varying crystallinity, the triazabicyclodecene-catalyzed copolymerization of the two constitutional isomers ε-caprolactone (εCL) and δ-caprolactone (δCL) was carried out at room temperature in toluene. Variation of the feed fraction of εCL from 50% to 80% and the detailed kinetic studies accompanied by application of terminal as well as nonterminal kinetic models suggested the formation of random copolymers. Differential scanning calorimetry and wide-angle X-ray scattering investigations revealed the decrease of melting temperatures and degree of crystallinity with the εCL fraction in the PCL. All copolymers were suited to obtain aqueous nanoparticle dispersions by means of nanoprecipitation. Encapsulation of the fluorescent probe pyrene confirmed a constant hydrophilic/hydrophobic balance of the nanoparticles.

Two different synthetic pathways give access to the amphiphilic block copolymer poly(ethylene oxide)‐block‐poly(tert‐butoxycarbonylaminomethylacrylate). In the first approach, two end‐functionalized segments are linked via click chemistry; and in the second approach, a poly(ethylene oxide) (PEO) based macroinitiator is chain extended via atom transfer radical polymerization (ATRP). In both cases the linking unit consists of an amide group, which is necessary to effectively deprotect the corresponding polymer precursor without cleavage of both segments. For this, amide‐containing ATRP initiators are employed and successful synthesis by nuclear magnetic resonance (NMR) and size exclusion chromatography (SEC) analyses before comparing both pathways is demonstrated. After deprotection, a novel double hydrophilic block copolymer, poly(ethylene oxide)‐block‐poly(dehydroalanine), is obtained, which is investigated using SEC (aqueous and DMSO) and 1H‐NMR spectroscopy. Containing a potentially zwitterionic PDha segment and a high density of both amino and carboxylic groups, pH‐dependent aggregation of the block copolymer is expected and is studied using dynamic light scattering, revealing interesting solution properties. The corresponding polymers are applied in various areas including drug delivery systems or in biomineralization.

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