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Synthesis of polyurethane‐type poly[3]rotaxanes is achieved by polyaddition between a cyclodextrin (CD)‐based [3]rotaxane diol and various diisocyanate species, which provide a more defined structure compared to conventional polyrotaxane syntheses. In this study, hydroxyl groups on CDs of [3]rotaxane diol are initially acetylated, and deprotected after the polyaddition to introduce polyurethane backbone structure into polyrotaxane framework. Despite a relatively complicated chemical structure, [3]rotaxane diol monomer is successfully synthesized in a high yield (overall 67%) without any taxing purification process, which is beneficial for practical applications. The polymerization itself proceeds well under a standard polyaddition reaction condition to afford corresponding polyurethanes around 80% yield with Mn > 30 kDa. The poly[3]rotaxanes show different aggregation behavior or optical properties, whether or not acetyl groups are present, and are analyzed by XRD, SEM, and fluorescence measurements. [ABSTRACT FROM AUTHOR]

An orthogonal agent having both alcohol and acylazide groups was used to construct novel polyurethanes by a simple synthetic process. Ring‐opening polymerization (ROP) of δ‐valerolactone from the orthogonal agent afforded a crystalline polymer having acylazide initiation end, while that of δ‐decanolactone resulted in an amorphous polymer. Since acylazide groups undergo thermally induced Curtius rearrangements to yield isocyanate groups, simple heating of above polymers gave macromonomers having both an isocyanate initiation end and an alcohol termination end, which afforded corresponding polyurethane by self‐polyaddition in a bulk condition without any additives. Meanwhile, kinetic analysis of the Curtius rearrangement revealed that a quantitative conversion was reached within a short reaction time, for example at 110°C for 30 min, or at 100°C for 1 h. Moreover, obtained polyurethane species showed unique self‐immolative type thermal degradation behavior. Considering the above, this orthogonal agent turned out to be useful to construct various polyurethane structures by a facile synthetic process, which would contribute to precise polymer synthesis and sequence defined polymer synthesis. [ABSTRACT FROM AUTHOR]

Polymer education relies on generally agreed terminology and nomenclature rules. The Polymer Division of the International Union of Pure and Applied Chemistry (IUPAC) generates and recommends such rules for naming processes and materials in polymer science. It is the goal of IUPAC that these recommendations be applied in polymer science curricula worldwide. For this purpose, a large amount of material has been provided by the Polymer Division of IUPAC, and in this paper these resources are described from the personal perspective of the authors. A discussion of terminology is then provided, including a detailed discussion of the term "dispersity" (M[subscript w]/M[subscript n]) and the rationale behind the recommended IUPAC names of different polymerization mechanisms. This is followed by a commentary on polymer nomenclature with examples. Finally, exemplary applications of resources provided by the Polymer Division of IUPAC for educational purposes around the world are presented.

The low melting points of solid polymer electrolytes (SPEs) based on the KTFSI electrolyte salt allow comparatively low operation temperatures (below 50 °C) for K‐ion batteries, unlike their Li or Na counterparts. Unfortunately, for this reason the electrolyte is also rendered mechanically unsuitable in its function to act as a cell separator. Therefore, in this work the use of inorganic nanofillers (Al2O3 and SiO2) is explored with the aim to improve rheological, thermal and cation transport properties of the resulting polymer composite electrolytes. Their electrochemical properties were further examined in K‐metal symmetrical cells and K‐metal/SPE/K2Fe[Fe(CN)6] cells and compared to corresponding liquid electrolyte systems. As a result of particle‐polymer interactions, filler‐containing SPEs showed higher degrees of crystallinity combined with filler polymer interaction and thus improved mechanical integrity in the relevant temperature range of 25–55 °C, while maintaining similar ionic conductivities than a filler‐free sample above the melting temperature. Although plating‐stripping experiments in symmetrical cell setups suggested high cell resistances for various compositions and in some cases even rapid cell failure, Al2O3‐based SPEs generally displayed high capacity retention when cycled against a positive electrode (here Prussian blue analogue K2Fe[Fe(CN)6]) over 100–160 cycles and possibly beyond. [ABSTRACT FROM AUTHOR]

The aggregation of a cyclodextrin (CD)‐based [3]rotaxane has been observed and analyzed in detail for the first time in this work. Although the hexagonal packing aggregation of CD‐based polyrotaxane is a well known phenomenon, corresponding studies in terms of rotaxanes without any polymer structure have not been conducted so far, probably owing to the difficulty of the molecular design. We synthesized a series of [3]rotaxane species by using a urea‐end‐capping method and evaluated their aggregation behavior by XRD and SEM measurements. [3]Rotaxane species containing native CD rings showed clear signals assigned to the hexagonal packing by XRD measurement as did polyrotaxane; this proved their aggregation capability. Because the corresponding per‐acetylated derivatives did not show this aggregation behavior, the driving force of this aggregation was suggested to be hydrogen bond formation among CD units. The effect of axle end structures and partial acetylation of CDs were also studied. [ABSTRACT FROM AUTHOR]

Poly(ethylene oxide) block copolymers (PEOz BCP) have been demonstrated to exhibit remarkably high lithium ion (Li+) conductivity for Li+ batteries applications. For linear poly(isoprene)-b-poly(styrene)-b-poly(ethylene oxide) triblock copolymers (PIxPSyPEOz), a pronounced maximum ion conductivity was reported for short PEOz molecular weights around 2 kg mol−1. To later enable a systematic exploration of the influence of the PIx and PSy block lengths and related morphologies on the ion conductivity, a synthetic method is needed where the short PEOz block length can be kept constant, while the PIx and PSy block lengths could be systematically and independently varied. Here, we introduce a glycidyl ether route that allows covalent attachment of pre-synthesized glycidyl-end functionalized PEOz chains to terminate PIxPSy BCPs. The attachment proceeds to full conversion in a simplified and reproducible one-pot polymerization such that PIxPSyPEOz with narrow chain length distribution and a fixed PEOz block length of z = 1.9 kg mol−1 and a Đ = 1.03 are obtained. The successful quantitative end group modification of the PEOz block was verified by nuclear magnetic resonance (NMR) spectroscopy, gel permeation chromatography (GPC) and differential scanning calorimetry (DSC). We demonstrate further that with a controlled casting process, ordered microphases with macroscopic long-range directional order can be fabricated, as demonstrated by small-angle X-ray scattering (SAXS), scanning electron microscopy (SEM) and transmission electron microscopy (TEM). It has already been shown in a patent, published by us, that BCPs from the synthesis method presented here exhibit comparable or even higher ionic conductivities than those previously published. Therefore, this PEOz BCP system is ideally suitable to relate BCP morphology, order and orientation to macroscopic Li+ conductivity in Li+ batteries. [ABSTRACT FROM AUTHOR]

Over the years, nitrogen‐rich functional groups like tetrazole and its derivatives have received increasing interest in the chemistry of small molecules. There is a continuously growing interest in polymers decorated with nitrogen for potential biomedical applications because of their broad range of biological properties, such as being antibacterial, anticarcinogenic, and anti‐inflammatory. On this premise, a new synthesis route is reported for nitrogen‐decorated polymers via the combination of Ugi‐azide four‐multicomponent reaction (UA‐4MCR) and thiol‐ene polymerization. Accordingly, α,ω‐diene monomers decorated with (bis‐)1,5‐disubstituted‐1H‐tetrazoles (bis‐1,5‐DS‐Ts) are synthesized by using the UA‐4MCR. Subsequently, the light‐induced thiol‐ene polymerization facilitates the efficient synthesis of novel tetrazole‐decorated polymers with apparent number average molecular mass (Mn) up to 62 000 g mol−1, which are characterized for their chemical, thermal, and optical properties. The comprehensive characterization of the synthesized polymers is paving the way toward a wealth of opportunities, ranging from biomaterials to energy storage−relevant materials. [ABSTRACT FROM AUTHOR]

Herein, a new method to synthesise epoxide-based sequence-controlled polymers via anionic ring-opening monomer addition, a form of anionic ring-opening polymerisation, is presented. This technique allows in combination with post-polymerisation modification (PPM) reactions for the successful preparation of modified mPEG-b-oligo(allyl glycidyl ether) featuring the incorporation of one repeating unit on average at a time. Due to the possible introduction of a vast variety of molecules to the polymeric system via PPM reactions, a multitude of advanced functional polymeric materials can be generated. This, in combination with the chain extension reactions, allows for the synthesis of well-controlled and programmable architectures with particular properties. The structure of the sequence-controlled polymer was confirmed via ¹H NMR spectroscopy, size exclusion chromatography, attenuated total reflection Fourier-transform infrared spectroscopy, and differential scanning calorimetry [ABSTRACT FROM AUTHOR]

The synergy of multicomponent reactions (MCRs) and metathesis chemistry is applied for the synthesis of bio‐based functional isosorbide polymers (i.e., polyesters) decorated with α‐acyloxy amide motif. The chemical structure of the polyesters that are not accessible by any other conventional methodologies is characterized in‐depth via nuclear magnetic resonance, size‐exclusion chromatography, and attenuated total reflectance infrared spectroscopy. It is also observed that the "biomass‐derived" carbon % of the polymers varied between 66.2 and 76.9. Moreover, the thermal properties of the novel isosorbide‐based polymers are investigated via thermogravimetric analysis and differential scanning calorimetry, revealing that the polymers are in the amorphous state, identified by the glass transition temperature (Tg) values below the human body temperature. The mechanical properties and the biocompatibility of the functional novel polyester derivative with the highest "biomass‐derived" carbon % are evaluated via dynamic mechanical analysis and cytotoxicity test. The exemplary polymer is biocompatible with chondrocyte cells in the conditions used in the tests. In summary, the complementary nature of isosorbide derivatives with MCRs and metathesis chemistry is utilized to illustrate the potential utility of isosorbide as a building block for polymers with prospective biomedical application (namely, as novel cartilage materials). [ABSTRACT FROM AUTHOR]

Researchers have dedicated their efforts for the creation of a wide choice of complex and precise macromolecular architectures over the past 100 years. Among them, cyclic polymers benefit from their absence of terminal chains and from their singular topology to minimize their hydrodynamic volume in solution, increase their chemical stability, limit their number of possible conformations as well as a reduce their propensity to crystallize or to form entanglements in comparison to their acyclic counterparts. While monocyclic structures have already been widely investigated and reviewed, reports on more complex polycyclic structures are rare. In this regard, cage‐shaped polymers—consisting of at least three polymer chains covalently interconnected through strictly two junction points—have received little attention over the past two decades. Although their synthesis is a worthy challenge, only a few synthetic methodologies of polymer cages were successfully developed so far. Thus, this review intends to highlight the key concepts of the conception of cage‐shaped polymers in addition to propose an actual and exhaustive state‐of‐art concept of their synthesis to rationally promote the next‐generation synthesis strategies. [ABSTRACT FROM AUTHOR]

Herein the decarboxylation of poly[N‐(acryloyloxy)phthalimide] (PAP) for the synthesis of functionalized polymers is reported. PAP homopolymer and block copolymers are used as precursor polymers for the straightforward functionalization via decarboxylation and subsequent Michael‐type addition or nitroxide radical coupling (NRC). [ABSTRACT FROM AUTHOR]

The polymerization of 2,3,4,5,6‐pentafluorobenzyl 2‐diazoacetate is conducted at ambient temperature and catalyzed by [(l‐prolinate)RhI(1,5‐dimethyl‐1,5‐cyclooctadiene)] or [(l‐prolinate)RhI(1,5‐cyclooctadiene)] yielding C1 polymers with molecular weights of 3000–4000 g mol−1 and dispersity between 1.1 and 1.3. Incorporation of the pentafluorobenzyl group into the C1 polymer results in a different solubility when compare to its C2 analog poly(2,3,4,5,6‐pentafluorobenzyl methacrylate). Efficient postmodifications via para‐fluoro‐thiol reaction with different thiols are conducted with this C1 polymethylene. [ABSTRACT FROM AUTHOR]

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The inverse vulcanization produces high sulfur content polymers from alkenes and elemental sulfur. Control over properties such as the molar mass or the solubility of polymers is not well established, and existing strategies lack predictability or require large variations of the composition. Systematic design principles are sought to allow for a targeted design of materials. Herein, we report on the inverse vulcanization of norbornenylsilanes (NBS), with a different number of hydrolysable groups at the silicon atom. Inverse vulcanization of mixtures of NBS followed by polycondensation yielded soluble high sulfur content copolymers (50 wt % S) with controllable weight average molar mass (MW), polydispersity (Đ), glass transition temperature (TG), or zero‐shear viscosity (η0). Polycondensation was conducted in the melt with HCl as a catalyst, abolishing the need for a solvent. Purification by precipitation afforded polymers with a greatly reduced amount of low molar mass species. [ABSTRACT FROM AUTHOR]