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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)., (© 2022 The Authors. Macromolecular Rapid Communications published by Wiley-VCH GmbH.)

Herein, the synthesis of polyethylene via an innovative post-polymerization modification (PPM) approach is reported. For this, a block copolymer of poly[ N -(acryloyloxy)phthalimide] (PAP) is synthesized by straightforward reversible addition-fragmentation chain-transfer (RAFT) polymerization using a dedicated macroRAFT transfer agent. Upon decarboxylation of the PAP block, followed by efficient block copolymer cleavage, a polyethylene homopolymer with a predictable degree of polymerization is obtained.

Living cationic polymerization is known for a good control over chain growth yielding polymers with well-defined molar mass distributions and low dispersities. However, the practical challenges involved in the synthesis of poly(vinyl ether)s limited suitable post-polymerization modifications (PPM) via chemoselective click reactions. Herein the successful controlled cationic polymerization of vinyl ethers bearing pendant CC double and C≡C triple bonds using a single-component initiation under ambient conditions is reported. Furthermore, the PPM via thiol-ene/-yne and copper(I)-catalyzed alkyne-azide cycloaddition reaction of the obtained polymers is successfully realized laying the foundation for the synthesis of unprecedented functional poly(vinyl ether)s., (© 2021 The Authors. Macromolecular Rapid Communications published by Wiley-VCH GmbH.)

The preparation of polymers containing sulfur-nitrogen bond derivatives, particularly 2,2,6,6-tetramethylpiperidine-1-sulfanyl (TEMPS) dimers (i.e., BiTEMPS), has been limited to free-radical or conventional step-growth polymerization as result of the inherent thermal lability of the BiTEMPS unit. Accordingly, a novel poly(diaminodisulfide) possessing the BiTEMPS functional group is synthesized via acyclic diene metathesis (ADMET) polymerization at 65-75 °C within 3 h with precise control over the primary polymer structure. Polymer is isolated with an M n of 20 400 g mol -1 and Ð of 1.9. Importantly, detailed nuclear magnetic resonance (NMR), size exclusion chromatography, attenuated total reflectance Fourier transform infrared (ATR-IR) in addition to elemental analysis studies of the BiTEMPS polymer confirm the successful polymerization, and show that the BiTEMPS unit remains intact during the polymerization process. Furthermore, the previously unexplored UV-responsiveness of the BiTEMPS decorated polymer backbone is investigated for the very first time., (© 2021 The Authors. Macromolecular Rapid Communications published by Wiley-VCH GmbH.)

Herein, a straightforward synthesis of a novel class of polymers, that is, poly(N-(4-vinylphenyl)sulfonamide)s, and their monomers is reported. A set of monomers with varying electron densities, fine-tuned by different substituents on the aromatic sulfonamide moiety, is polymerized by free radical polymerization featuring low molar masses (2300  ≤ M n  ≤ 3200 g mol -1 ) and low dispersities (1.15 ≤ Đ ≤ 1.47). Further, the post-polymerization modification of the obtained polymers via aza-Michael addition with electron-deficient alkenes is demonstrated using organic superbases as catalysts, paving the way toward the facile synthesis of novel polymeric protected β-amino acid derivatives., (© 2021 The Authors. Macromolecular Rapid Communications published by Wiley-VCH GmbH.)

A sulfur-based self-condensation method is investigated as an efficient tool for the synthesis of polythiophene derivatives. The reaction proceeds through multicomponent redox polycondensation between readily available diketone compounds and elemental sulfur in the presence of a Brønsted acid/base pair. Six different diketone derivatives have been screened and the polymerization is generalized by the synthesis of so-far-unprecedented alternating copolymers based on 2,4-thiophene/arene repeating units. By exploiting microwave heating the synthetic procedure is optimized, particularly for alternating copolymers containing aryl and thiophene units, such that a copolymer can be synthesized in only 24 h compared to the conventional process taking 6 d, yielding polymers within the same apparent weight average molar mass (M w ). All obtained copolymers are analyzed in detail using size exclusion chromatography (SEC), nuclear magnetic resonance (NMR), attenuated total reflectance infrared spectroscopy (ATR-IR), thermal gravimetric analysis and differential scanning calorimetry (DSC)., (© 2021 The Authors. Macromolecular Rapid Communications published by Wiley-VCH GmbH.)

Polymers with sulfur-nitrogen bonds have been underestimated for a long time, although the intrinsic characteristics of these polymers offer a myriad of superior properties (e.g., degradation, flame retardancy, film-forming ability, good solubility in polar solvents, and high refractivity with small chromatic dispersions, among other things) compared to their carbon analogues. The remarkable characteristics of these polymers result from the unique chemical properties of the sulfur-nitrogen bond (e.g., its polar character and the multiple valence states of sulfur), and thus open excellent perspectives for the development of innovative (bio)materials. Accordingly, this review describes the most common chemical approaches toward the efficient synthesis of these ubiquitous polymers possessing diverse sulfur-nitrogen bonds, and furthermore highlights their applications in multiple fields, ranging from biomedicine to energy storage, with the aim of providing an informative perspective on challenges facing the synthesis of sulfur-nitrogen polymers with desirable properties., (© 2020 The Authors. Published by WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.)

Sulfur and its functional groups are major players in an area of exciting research taking place in modern polymer and materials science, both in academia and industry. In fact, manifold sulfur-based reactions that are both exceptionally versatile as well as tremendously useful have been implemented, and further utilized for the design and preparation of polymeric materials that lead to a plethora of applications ranging from medicine to optics and nanotechnology to separation science. Hence, within this review, an overview of strategies and developments used over the last 5 years to reinforce the importance of the sulfur functional group in modern polymer and materials science is presented. In particular, many important references in the primary literature of sulfur chemistry are referred to, including thiol-ene, thiol-yne, thiol-Michael addition, disulfide cross-linking, and thiol-disulfide exchange, among others, by explaining and illustrating the important principles. Last but not least, the grand aim to underpin the importance of sulfur in modern polymer and materials science is achieved by presenting selected examples in diverse fields and postulating the respective potential for real-world applications., (© 2018 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.)

A well-defined amphiphilic triblock copolymer, poly[(ethylene glycol)methyl ether]-block-poly(N,N-dimethylamino ethyl methacrylate-co-2,2,2-trifluoroethyl methacrylate)-block-poly(4-(4-methoxy-phenylazo)phenoxy methacrylate) (PEG-b-P(DMAEMA-co-TFEMA)-b-PMEPPMA), is successfully synthesized by stepwise atom transfer radical polymerization. Owing to its amphiphilic nature, PEG-b-P(DMAEMA-co-TFEMA)-b-PMEPPMA can self-assemble into vesicles in aqueous solution and exhibits a reversible triple-responsive behavior toward CO 2 , O 2 , and light stimuli. More importantly, such vesicles can exhibit a controlled "breathing" behavior via external stimuli due to their suitable chemical structure and stimuli responsiveness. Consequently, these vesicles can be employed as nanocarriers for rate-tunable controlled release via adjustment of their membrane permeability by a single stimulus or various stimuli combinations., (© 2017 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.)

Thermoresponsive and active functional fiber mats were prepared from random copolymer of poly(pentafluorophenyl acrylate-co-N-isopropylacrylamide) (P(PFPA-co-NIPAM)), which was synthesized by a controlled radical polymerization process based on reversible addition-fragmentation chain transfer (RAFT). As reactive sites, pentafluorophenyl ester (PFP) groups were incorporated in the copolymer to allow for a multiple post-polymerization modification. UV-cross-linkable moieties were first introduced by partially reacting PFP groups in the copolymer with ortho-nitrobenzyl (ONB)-protected diamine. Electrospinning the resulting ONB-containing P(PFPA-co-NIPAM), followed by UV-induced cross-linking, yielded stable cross-linked thermoresponsive PNIPAM-based fiber mats. The remaining PFP active groups on the surface of copolymer fiber mats allowed for further conjugation with an H-Gly-Arg-Gly-Asp-Ser-OH (GRGDS) peptide, a well-known cell adhesive peptide sequence that was selected as a model in order to promote cell growth. At 37 °C, fibroblast cells were found to attach, spread, and proliferate well on the GRGDS-immobilized cross-linked (CL) fiber mat, as opposed to those on the GRGDS-immobilized un-cross-linked (UCL) fiber mat. By decreasing the temperature down to 20 °C, i.e. below the lower critical solution temperature (LCST) of thermoresponsive PNIPAM, cultured cells could easily be released from both GRGDS-immobilized CL and UCL fiber mats, whereas no cells were detached from tissue culture polystyrene (TCPS). These results suggest that the thermosensitive and active functional fiber mat obtained in this research represent an attractive and versatile platform for cultured cell recovery, which is beneficial for tissue engineering applications.

Zwitterionic thin films containing α-amino phosphonic acid moieties were successfully introduced on silicon surfaces and their antifouling properties were investigated. Initially, the substrates were modified with a hybrid polymer, composed of poly(methylsilsesquioxane) (PMSSQ) and poly(4-vinyl benzaldehyde) (PStCHO). Next, a Kabachnik-Fields post-polymerization modification (sur-KF-PMR) of the functionalized aldehyde surfaces was conducted with different amines and dialkyl phosphonates. After subsequent deprotection reaction of dialkyl phosphonates, the obtained zwitterionic surfaces were characterized by various techniques and we found excellent antifouling properties of the resulting films., (© 2015 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.)

Emission wavelength control in fluorescent nanoparticles (NPs) is crucial for their applications. In the case of inorganic quantum dots or dye-impregnated silica NPs, such a control is readily achieved by changing the size of the particles or choosing appropriate fluorescent dyes, respectively. A similar modular approach for controlling the emission wavelength of fluo-rescent polymer NPs, however, is difficult. This article reports on fluorescent polymer NPs, the synthesis of which provides a platform for a modular approach towards the preparation of fluorescent NPs of desired emission wavelength. Atom-transfer radical polymerization (ATRP) is employed to synthesize reactive ester polymers, which are then easily modified with a commercially available dye and subsequently subjected to nanoprecipitation. The resulting NPs, with low size polydispersity, show an enhanced emission quantum yield when compared with the same dye molecules in solution., (© 2015 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.)

Novel thermosensitive nanocomposite (NC) hydrogels consisting of organic/inorganic networks are prepared via in situ free radical polymerization of 2-(2-methoxyethoxy) ethyl methacrylate (MEO2 MA) and oligo(ethylene glycol) methacrylate (OEGMA) in the presence of inorganic cross-linker clay in aqueous solution. The obtained clay/P(MEO2 MA-co-OEGMA) hydrogels exhibit double volume phase transition temperatures, an upper critical solution temperature (UCST), and a lower critical solution temperature (LCST), which can be controlled between 5 and 85 °C by varying the fraction of OEGMA units and the weight percentage of cross-linker clay. These new types of NC hydrogels with excellent reversible thermosensitivity are promising for temperature-sensitive applications such as smart optical switches., (© 2015 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.)

Temperature-triggered formation of nanostructures with distinct biological activity offers opportunities in selective modification of matrices and in drug delivery. Toward these ends, diblock polymers comprising poly(diethylene glycol methyl ether methacrylate) (PDEGMEMA) conjugated to a triple helix-forming collagen-like peptide were produced. Triggered by the collapse of the thermoresponsive domain above its LCST, the conjugate undergoes a reversible transition in aqueous solution to form well-defined nanovesicles with diameters of approximately 100 nm, with a transition temperature of 37 °C. The incorporation of CLP domains in these nanostructures may offer opportunities for the selective targeting of collagen-containing matrices., (© 2015 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.)

Activated ester polymers, pioneered by Ferruti and Ringsdorf in the 1970s, are attractive polymeric materials because they can easily be converted into functional polymers by reacting with amine nucleophiles. In the present study, methyl salicylate acrylate, salicyl acrylate, and tert-butyl salicylate acrylate monomers were polymerized yielding three novel reactive precursors suitable for the postpolymerization modification with primary and secondary amines. The reactivities of poly(pentafluorophenyl acrylate), poly(methyl salicylate acrylic ester), and poly(salicyl acrylate) toward amines were compared by kinetic studies and revealed the practical applicability of salicylic acid based derivatives for efficient postpolymerization modifications. In addition, in vitro cytotoxicity of water-soluble leaving groups, pentafluorophenol and salicylic acid, as well as water-soluble polymers containing the respective activated ester groups were investigated using HeLa cells. In short, compared to the frequently used poly(pentafluorophenyl acrylate), poly(salicyl acrylate) activated ester feature a lower reactivity, but exhibit less cytotoxicity. In this respect, poly(salicyl acrylate) as reactive precursor polymers may become alternative routes for the synthesis of functional polyacrylamides when it comes to advanced applications in vivo.

This Review focuses on the recent progress in the area of CO2 -responsive polymers and provides detailed descriptions of these existing examples. CO2 -responsive polymers can be categorized into three types based on their CO2 -responsive groups: amidine, amine, and carboxyl groups. Compared with traditional temperature, pH, or light stimuli-responsive polymers, CO2 -responsive polymers provide the advantage to use CO2 as a "green" trigger as well as to capture CO2 directly from air. In addition, the current challenges of CO2 -responsive polymers are discussed and the different solution methods are compared. Noteworthy, CO2 -responsive polymers are considered to have a prosperous future in various scientific areas., (Copyright © 2013 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.)

An excess of elemental sulfur is generated annually from hydrodesulfurization in petroleum refining processes; however, it has a limited number of uses, of which one example is the production of sulfuric acid. Despite this excess, the development of synthetic and processing methods to convert elemental sulfur into useful chemical substances has not been investigated widely. Here we report a facile method (termed 'inverse vulcanization') to prepare chemically stable and processable polymeric materials through the direct copolymerization of elemental sulfur with vinylic monomers. This methodology enabled the modification of sulfur into processable copolymer forms with tunable thermomechanical properties, which leads to well-defined sulfur-rich micropatterned films created by imprint lithography. We also demonstrate that these copolymers exhibit comparable electrochemical properties to elemental sulfur and could serve as the active material in Li-S batteries, exhibiting high specific capacity (823 mA h g(-1) at 100 cycles) and enhanced capacity retention.

Substituted polyphenylacetylenes featuring reactive pentafluorophenyl (PFP) ester moieties are synthesized. Parts of the reactive PFP groups are then converted with a mono ortho-nitrobenzyl-protected diamine in variable ratios. Thin films are prepared from these copolymers and irradiated with UV light (λ = 365 nm), resulting in crosslinking of the irradiated areas and hence enabling a photopatterning. We found that during the photocrosslinking process, the excess of PFP ester moieties is stable and remained intact, enabling a subsequent post-polymerization modification step with amines. Noteworthy, this subsequent modification with amines results in a dramatically shift in the UV-vis absorption spectra, rendering these patterned conjugated polymer films ideal candidates for optical sensors., (Copyright © 2013 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.)

Scale formation, the deposition of certain minerals such as CaCO3, MgCO3, and CaSO4·2H2O in industrial facilities and household devices, leads to reduced efficiency or severe damage. Therefore, incrustation is a major problem in everyday life. In recent years, double hydrophilic block copolymers (DHBCs) have been the focus of interest in academia with regard to their antiscaling potential. In this work, we synthesized well-defined blocklike PAA-PAMPS copolymers consisting of acrylic acid (AA) and 2-acrylamido-2-methyl-propane sulfonate (AMPS) units in a one-step reaction by RAFT polymerization. The derived copolymers had dispersities of 1.3 and below. The copolymers have then been investigated in detail regarding their impact on the different stages of the crystallization process of CaCO3. Ca(2+) complexation, the first step of a precipitation process, and polyelectrolyte stability in aqueous solution have been investigated by potentiometric measurements, isothermal titration calorimetry (ITC), and dynamic light scattering (DLS). A weak Ca(2+) induced copolymer aggregation without concomitant precipitation was observed. Nucleation, early particle growth, and colloidal stability have been monitored in situ with DLS. The copolymers retard or even completely suppress nucleation, most probably by complexation of solution aggregates. In addition, they stabilize existing CaCO3 particles in the nanometer regime. In situ AFM was used as a tool to verify the coordination of the copolymer to the calcite (104) crystal surface and to estimate its potential as a growth inhibitor in a supersaturated CaCO3 environment. All investigated copolymers instantly stopped further crystal growth. The carboxylate richest copolymer as the most promising antiscaling candidate proved its enormous potential in scale inhibition as well in an industrial-filming test (Fresenius standard method).

The successful sequence-controlled installation of an activated ester using a newly designed monomer pentafluorophenyl 4-maleimidobenzoate is demonstrated. Pentafluorophenyl 4-maleimidobenzoate is kinetically installed at different stages of a nitroxide-mediated polymerization, namely, near the α-chain end and in the middle of a PS chain. In addition, successful installation of apolar and polar functional groups is achieved via post-polymerization functionalization, which demonstrated the versatility of the synthesis of a universal precursor for locally functionalized polymers., (Copyright © 2012 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.)

We describe the reconstitution of apo-horse radish peroxidase (apo-HRP) onto TiO(2) nanorods functionalized with a multifunctional polymer. After functionalization, the horse radish peroxidase (HRP) functionalized TiO(2) nanorods were well dispersible in aqueous solution, catalytically active and biocompatible, and they could be used to quantify and image H(2)O(2) which is a harmful secondary product of cellular metabolism. The shape, size and structure of TiO(2) nanorods (anatase) were analyzed by transmission electron microscopy (TEM), high resolution TEM (HRTEM), electron diffraction (ED) and X-ray diffraction (XRD). The surface functionalization, HRP reconstitution and catalytic activity were confirmed by UV-Vis, FT-IR, CLSM and atomic force microscopy (AFM). Biocompatibility and cellular internalization of active HRP reconstituted TiO(2) nanorods were confirmed by a classical MTT cytotoxicity assay and confocal laser scanning microscopy (CLSM) imaging, respectively. The intracellular localization allowed H(2)O(2) detection, imaging and quantification in HeLa cells. The polymer functionalized hybrid system creates a complete sensor including a "cell positioning system" in each single particle. The flexible synthetic concept with functionalization by post-polymerization modification allows introduction of various dyes for sensitisation at different wavelengths and introduction of various anchor groups for anchoring on different particles.

We report on triple responsive polymers, exhibiting a distinct and reversible lower critical solution temperature in water that can be altered by light and redox stimuli, and we suggest their evaluation for molecular information processing., (This journal is © The Royal Society of Chemistry 2011)

A poly(oligo(ethylene glycol) monomethyl ether methacrylate)-block-poly(N-isopropyl methacrylamide) (POEGMA-b-PNIPMAM) block copolymer with a biotin end group on the PNIPMAM block as a biotarget was synthesized as a model system for temperature-controlled polymer immobilization. The synthesis was based on RAFT polymerization followed by postpolymerization modification of an activated ester precursor block and an exchange of the dithioester end group within one step. NMR, differential scanning calorimetry (DSC), dynamic light scattering (DLS), and turbidimetry measurements were performed to investigate the stimulus-responsive properties. The double thermoresponsive POEGMA-b-PNIPMAM with biotin end group showed a temperature-dependent multistage assembly behavior as it was completely soluble in water at temperatures below the LCST of both blocks, formed micellar structures above the LCST of PNIPMAM but below the LCST of POEGMA, or precipitated from solution above the LCST of both blocks. At room temperature, the polymer could be immobilized onto a streptavidin surface via its biotin end group, as shown in surface plasmon resonance (SPR) experiments. At 50 °C, at which the block copolymer formed micelles trapping the biotin target within the PNIPMAM core, no immobilization was observed, showing that the biological binding ability of the model could be controlled via external stimuli.

We describe the synthesis and characterization of a cross-linkable siloxane-derivatized tetraphenylbenzidine (DTMS-TPD), which was used for the fabrication of semiconducting highly ordered nanorod arrays on conductive indium tin oxide or Pt-coated substrates. The stepwise process allow fabricating of macroscopic areas of well-ordered free-standing nanorod arrays, which feature a high resistance against organic solvents, semiconducting properties and a good adhesion to the substrate. Thin films of the TPD derivate with good hole-conducting properties could be prepared by cross-linking and covalently attaching to hydroxylated substrates utilizing an initiator-free thermal curing at 160 degrees C. The nanorod arrays composed of cross-linked DTMS-TPD were fabricated by an anodic aluminum oxide (AAO) template approach. Furthermore, the nanorod arrays were investigated by a recently introduced method allowing to probe local conductivity on fragile structures. It revealed that more than 98% of the nanorods exhibit electrical conductance and consequently feature a good electrical contact to the substrate. The prepared nanorod arrays have the potential to find application in the fabrication of multilayered device architectures for building well-ordered bulk-heterojunction solar cells.

Reversible addition-fragmentation chain transfer (RAFT) polymerization was used to synthesize poly[diethylene glycol monomethylether methacrylate] (PDEGMA) (M(n) = 6250 g/mol, PDI = 1.14) with a pentafluorophenyl (PFP) activated ester and a dithioester end group. The hormone thyroxin (T4) was quantitatively attached to the PFP activated ester alpha end group via its amino group. The omega-terminal dithioester was not harmed by this reaction and was subsequently aminolyzed in the presence of N-biotinylaminoethyl methanethiosulfonate, yielding a polymer with a thyroxin and a biotin end group with very high heterotelechelic functionality. The polymer was characterized by (1)H, (13)C, and (19)F NMR, UV-vis, and IR spectroscopy and gel permeation chromatography. The thyroxin transport protein prealbumin with two thyroxin binding sites and streptavidin, which has four biotin binding sites, was conjugated using the biotarget labeled polymer, resulting in the formation of a protein-polymer network, confirming the heterotelechelic nature of the polymer. Polymer-protein microgel formation was observed with dynamic light scattering. To realize a directed protein assembly, prealbumin was immobilized onto a surface, exposing one of its two thyroxin binding groups and thus allowing the conjugation with the thyroxin alpha end group of the heterotelechelic polymer. The biotin omega end group of the attached polymer layer enabled the subsequent immobilization of streptavidin, yielding a defined multilayer system of two proteins connected with the synthetic polymer (efficiency of streptavidin immobilization 81% based on prealbumin). Without the polymer, no streptavidin immobilization occurred. The layer depositions were monitored by surface plasmon resonance. The synthetic approach of combining PFP activated esters with functional MTS reagents presents a powerful method for obtaining well-defined heterotelechelic (bio-) functionalized polymers.

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]

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]

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]

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]

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]

The existing recommendations for the structure-based nomenclature of regular single-strand organic polymers are extrapolated to complex polymers. The key proposal is that polymeric moieties may be named substituents. The types of polymers covered include linear and branched polymers containing more than one block of a single type of constitutional repeating unit (CRU) and branched polymers containing a main chain from which one or more polymeric side chains emanate. [ABSTRACT FROM AUTHOR]

Recently, new methods have been developed for the utilization of elemental sulfur as a feedstock for novel polymeric materials. One promising method is the inverse vulcanization, which is used to prepare polymeric structures derived from sulfur and divinyl comonomers. However, the mechanical and electrical properties of the products are virtually unexplored. Hence, in the present study, we synthesized a 200 g scale of amorphous, hydrophobic as well as translucent, hyperbranched polymeric sulfur networks that provide a high thermal resistance (>220 °C). The polymeric material properties of these sulfur copolymers can be controlled significantly by varying the monomers as well as the feed content. The investigated comonomers are divinylbenzene (DVB) and 1,3-diisopropenylbenzene (DIB). Plastomers with low elastic content and high shape retention containing 12.5%-30% DVB as well as low viscose waxy plastomers with a high flow behavior containing a high DVB content of 30%-35% were obtained. Copolymers with 15%-30% DIB act, on the one hand, as thermoplastics and, on the other hand, as vitreous thermosets with a DIB of 30%-35%. Results of the thermogravimetric analysis (TGA), the dynamic scanning calorimetry (DSC) and mechanical characterization, such as stress-strain experiments and dynamic mechanical thermal analysis, are discussed with the outcome that they support the assumption of a polymeric cross-linked network structure in the form of hyper-branched polymers. [ABSTRACT FROM AUTHOR]

ABSTRACT The present study investigates the challenging approach of post-polymerization modification on polymers with a sterically demanding reaction center. Therefore, the general possibility to functionalize polymethylene moieties was investigated. Poly(benzyl 2-ylidene-acetate) was synthesized by polymerization of benzyl 2-diazoacetate utilizing [( L-prolinate)RhI(1,5-dimethyl-1,5-cyclooctadiene)] as a catalyst. Subsequently, the modification of C1 polymerized poly(benzyl 2-ylidene-acetate) with amines was analyzed and the obtained data set was compared with experimental data derived for the C2 analog poly(benzyl acrylate). This is the first study on post-polymerization modification utilizing densely functionalized polymethylenes as starting materials. © 2015 Wiley Periodicals, Inc. J. Polym. Sci., Part A: Polym. Chem. 2016, 54, 686-691 [ABSTRACT FROM AUTHOR]

We have investigated the surface reorganization characteristics of a novel amphiphilic diblock copolymer, poly(acetic acid-2-(2-(4-vinyl-phenoxy)-ethoxy)-ethylester)-block-polystyrene (PAEES-b-PS), in response to varying interfaces from air to water and vice-versa at various temperatures. The surface reorganization characteristics of the block copolymer films was monitored by scanning force microscopy, in order to delineate the kinetically controlled morphological process of surface reorganization of a diblock copolymer, with a particular emphasis on the phase contrast signal which allowed the determination of local composition patterns of PAEES-b-PS at the surface. Upon heating a water-annealed sample in air, the initially hydrophilic liquid-like surface exhibited a typical dewetting pattern comprising holes and elevations of different copolymer components. In contrast, air-annealed samples with glassy polystyrene surfaces exhibited a distinctly different reorganization pattern upon heating in water, possibly due to the swelling of the underlying liquid-like hydrophilic block by penetrated water. In both air and water environments, the major surface reorganization occurred around 70℃, well below the glass transition temperature (100℃) of the higher Tg block, polystyrene, in the copolymer. [ABSTRACT FROM AUTHOR]

Polymer education in South Korea is described in connection with the industrialization of the country after the Korean War. Adversities such as the destruction of production facilities during the war had to be overcome before industrialization and development of plastics industry dynamically took off. Different approaches of polymer education in universities and scientific societies in South Korea are described. Short courses and polymer education through the internet are also mentioned. Industrial production of electronic devices (TV sets, mobile phones), automotive and ship-building industry requires highly skilled scientists and engineers to provide the necessary polymeric materials. Devotion of people in Korea to education, including polymer education, might play an important role in the present prosperity of South Korea. [ABSTRACT FROM AUTHOR]

The present article provides an up-to-date overview of the education in polymer science as part of the chemical education in Germany. With the change from the renowned 'Diplom' curriculum to a Bachelor-Master educational system, the educational landscape in Germany has transformed. The intention of this report is to offer German and also foreign students a first overview about polymer education in Germany and the chance to participate. With the change to the globally known Bachelor-Master education system, students have the possibility to study polymer science at any level ranging from Bachelor degree to a postdoctoral study. [ABSTRACT FROM AUTHOR]

Altering the surface wettability by external stimulation has received great attention recently. While different stimuli, such as temperature, pH, etc. can be applied for this purpose, light combines several advantages. It is a contact-free stimulation, which can be applied locally, thereby allowing a versatile patterning. This review article summarizes recent developments in the area of polymers that allow a light-induced change in surface wettability. For this purpose, different photochromic dyes have been incorporated into polymers, which enable a photo-isomerization upon light irradiation resulting in a change in polarity. Several examples based on azobenzene or spiropyran will be discussed, but also some more exotic examples, such as those based on salicylideneaniline, will be highlighted. The different approaches how to apply these photochromic dyes to various surfaces are presented and discussed. Additionally, the combination with other stimuli-responsive moieties will be explored and the paper will be concluded by mentioning the remaining challenges and by providing a future perspective. [ABSTRACT FROM AUTHOR]

ABSTRACT In this study, we succeeded in the in situ activation of nonactivated ester moieties embedded in polymer structures. Although poly(pentafluorophenyl methacrylate) (PPFPMA) can react with 2-ethylhexylamine at 50 °C in the presence of proton scavenger such as NEt3, such conditions were not suitable for poly(phenyl methacrylate) (PPhMA). Nevertheless, the combination of organo-activating agents, namely 1,8-diazabicyclo[5.4.0]undec-7-ene (DBU) and 1,2,4-triazole (TZ) led to a facile conversion from ester to amide for PPhMA. The reaction between PPhMA and 2-ethylhexylamine was conducted at 120 °C in the presence of one equivalent of TZ and three equivalents of DBU and yielded >99% ester conversion to afford corresponding polymethacrylamide derivatives as confirmed by FT-IR and 1H NMR measurements. In addition, poly(2,2,2-trifluoroethyl methacrylate) (PTFEMA) and poly(methyl methacrylate) (PMMA) were also allowed to react with amines in the presence of the organo-activating agents with dramatically increased conversions (>70%). © 2014 Wiley Periodicals, Inc. J. Polym. Sci., Part A: Polym. Chem. 2014, 52, 1353-1358 [ABSTRACT FROM AUTHOR]

A Mitsunobu reaction of trifluoroacetamide (TFA amide) and alcohols is used in a post-polymerization modification process. The reaction is conducted on polystyrene (PSt) bearing 20 mol% TFA amide groups with 4-methyl benzyl alcohol in the presence of a N,N,N′,N′-tetramethylazodicarboxamide and tributylphosphine as mediators. The Mitsunobu reaction on polymer proceeds efficiently, as confirmed by the obvious precipitation generation during the reaction and the conversion of TFA amide moiety reached 88.6% confirmed by 19F NMR measurement, yielding PSt bearing tertiary TFA amide moieties. The obtained polymers featuring tertiary TFA amide moieties are deprotected in the presence of tetrabutylammonium hydroxide as a base to afford corresponding polymers featuring functionalized polyamine scaffolds with 92.5% conversion. In addition, the precise structural assignment is proven by synthesis and analysis of the model monomeric compounds and the respective model polymers. [ABSTRACT FROM AUTHOR]

RAFT polymerization of 4-acryloxyphenyldimethylsulfoniumtriflate (SR-AEM) using pentafluorophenyl-(4-phenylthiocarbonylthio-4-cyanovalerate)as the chain transfer agent and AIBN as a radical source in acetonitrileat 90 °C yielded poly(4-acryloxyphenyldimethylsulfonium triflate)(poly(SR-AEM))s in high yields with well-controlled molecular weightsand polydispersity indices. The reactive polymer poly(SR-AEM) wasconverted using an excess amount of amines, e.g., isopropylamine yieldingpredominantly poly(N-isopropylacrylamide) with defectsof poly(4-acryloxyphenyl methylsulfide) in a minor ration of lessthan 16%. Furthermore, poly(SR-AEM) could be converted by thermo-triggeredrelease of methyl group at dimethylsulfonium ion group to afford poly(4-acryloxyphenylmethylsulfide) (poly(APM)) as proved by 1H NMR measurements,which did not react with amines anymore. To the best of our knowledge,this represents the first temperature-induced “on–offswitching” of the reactivity of an activated ester by using4-dimethylsulfonim phenol as the stimuli-responsive leaving group. [ABSTRACT FROM AUTHOR]

Nanostructures play a significant role in introducing distinctive functionality to materials. A synergistic combination of nanofabrication techniques with material properties holds great promise in creating smart biomimetic structures. An advanced preparation technique to fabricate complex and sophisticated hierarchical polymeric nanostructure templates via anodized alumina oxide membranes is highlighted. Moreover, nanostructures made of responsive polymers activated by environmental stimuli offer a huge potential in a wide range of applications by enhancing their responsiveness. The current state of research on novel nanostructures fabrication by integrating anodic aluminum oxide with stimuli‐responsive polymers is presented, with an emphasis on the underlying actuation mechanism in terms of application. Furthermore, the potential direction for future research is discussed. [ABSTRACT FROM AUTHOR]