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In this survey, the different weight ratios of polybenzimidazole (PBI)/polyvinyl alcohol (PVA) blend polymer membranes were produced using the solution‐casting method. The crosslinking agents of phosphoric acid (PA) and glutaraldehyde (GA) were studied separately to prevent the PVA water solubility in the PBI/PVA blend membrane structure. The GA crosslinking (24 h) successfully prevented membrane solubility, reducing it to below 1%. The chemically crosslinked blend membrane (Cr‐PBI/PVA‐9:1) has the highest proton conductivity result which is 0.209 S cm−1 at 80°C and it has excellent oxidative stability since the membrane only lost 4% of its weight in a Fenton agent after 96 h. The Cr‐PBI/PVA‐9:1 also has higher proton conductivity than the commercial PBI membrane (0.122 S cm−1 at 80°C). The glass transition temperature of the synthesized Cr‐PBI/PVA‐9:1 blend membrane is greater than the synthesized PBI membrane (390°C). The current density and power density measured at 0.6 V for the synthesized Cr‐PBI/PVA‐9:1 membrane were found to be 504 mA cm−2and 251 mW cm−2. This work sheds light on the potential use of PVA in PEMFC applications by mixing PVA with a high‐temperature polymer like PBI and crosslinking the membrane with a prepared GA crosslinking agent. [ABSTRACT FROM AUTHOR]

Semi‐aromatic nylon MXD6 shows superior mechanical strength and gas barrier properties. To improve its toughness and get sight into its excellent properties, a series of poly(m‐xylylene adipamide‐co‐isophthalamide) (MXD6/I) random copolyamides were synthesized using adipic acid, isophthalic acid (IPA) and m‐xylylene diamine as monomers via direct melt polycondensation. The effect of IPA content on the thermal, crystallization, heat resistant, mechanical, and barrier properties of the copolyamides were systematically investigated. The results showed that the increase of IPA content from 0 to 12 mol% resulted in a decrease in the melting point of the copolyamides from 238 to 217°C but the glass transition temperature (Tg) increased from 88 to 105°C. Correspondingly, the Vicat softening temperature decreased from 199.2 to 172.5°C. The crystallization rate of the copolyamides significantly decreased with the increase of the IPA content. The copolyamides had improved elongation and rupture energy and decent oxygen barrier properties with the introduction of IPA. It is expected that this study would guide design of MXD6 macromolecular chain structure to prepare high‐performance MXD6 materials. [ABSTRACT FROM AUTHOR]

Eugenol-containing oligoorganosilsesquioxanes were synthesized by the method of hydrolytic polycondensation in an active medium under various reaction conditions. The obtained products were characterized by 29Si NMR spectroscopy and MALDI-TOF spectrometry. It was shown that factors such as the reaction temperature, polycondensation duration, and molar ratio between the initial alkoxysilane monomer and acetic acid may affect the molecular weight characteristics and molecular structure of the formed oligomer, like the content of stressed cyclic units (T3, DTT, TDT) and unstressed silsesquioxane units TnDm. In particular, an increase in the ratio of the initial reagents led to an increase in the content of silsesquioxane Tn fragments from 28.2%mol to 41.7%mol, while the number of strained cyclic structures decreased by more than two times. An increase in the synthesis time is of no particular practical value since it was found that the composition of the oligomers synthesized for 6 h and 12 h was practically identical, as was that of the oligomers synthesized for 24 h and 48 h. A noticeable transition in the oligomer composition was observed only when the synthesis time was changed from 12 h to 24 h. Finally, it was shown that the choice of synthesis temperature had the strongest effect on the oligomer composition. The oligomer synthesized at 95 °C contained the highest amount of silsesquioxane Tn fragments, >77%mol, while a Tn fragment content of ~42%mol was observed during the synthesis at 117 °C. It was shown that silsesquioxanes are devitrified at room temperature (Tg from −6.4 to −10.6 °C), and their thermal stability in an inert atmosphere is 300 °C. The synthesized oligomers, due to the presence of hydroxyl-containing eugenol units, may be promising binders and additives for functional epoxy–silicone paints and coating materials. [ABSTRACT FROM AUTHOR]

This study focuses on the development of environmentally sustainable polypropylene (PP)-based composites with the potential for biodegradability by incorporating cellulose and the oligomeric siloxane ES-40. Targeting industrial applications such as fused deposition modeling (FDM) 3D printing, ES-40 was employed as a precursor for the in situ formation of silica particles via hydrolytic polycondensation (HPC). Two HPC approaches were investigated: a preliminary reaction in a mixture of cellulose, ethanol, and water, and a direct reaction within the molten PP matrix. The composites were thoroughly characterized using rotational rheometry, optical microscopy, differential scanning calorimetry, and dynamic mechanical analysis. Both methods resulted in composites with markedly reduced crystallinity and shrinkage compared to neat PP, with the lowest shrinkage observed in blends prepared directly in the extruder. The inclusion of cellulose not only enhances the environmental profile of these composites but also paves the way for the development of PP materials with improved biodegradability, highlighting the potential of this technique for fabricating more amorphous composites from crystalline or semi-crystalline polymers for enhancing the quality and dimensional stability of FDM-printed materials. [ABSTRACT FROM AUTHOR]

Highlights The demand for polymers with antibacterial properties is increasing in food packaging industry and medical supplies. Antibacterial additives without toxic metal ion release are crucial for health and safety but still have challenges. Herein, polypropylene (PP) nanocomposite was prepared with polyaniline/graphene nanocomposite (PANI/GNP) as a green antibacterial additive due to its electrostatic, free radical, and nanoknife effect synergistic antibacterial mechanisms. To improve the dispersibility of PANI/GNP, nanosilica coating on PANI/GNP was constructed successfully with in situ condensation polymerization of epoxy functionalized ethyl orthosilicate to obtain EP‐nSiO2‐PANI/GNP. EP‐nSiO2‐PANI/GNP with a thin nanosilica coating has a significantly improved thermal stability as compared with that of PANI/GNP characterized by TGA. The EP‐nSiO2‐PANI/GNP presents a nanoscale disperse state in PP nanocomposite and thus enhances the melt viscosity and storage modulus accordingly characterized by TEM and Rheology. The EP‐nSiO2‐PANI/GNP/PP filled with 0.5 wt% of EP‐nSiO2‐PANI/GNP demonstrates antibacterial activity of 100% against both Escherichia coli and Staphylococcus aureus. In situ condensation polymerization to prepare EP‐nSiO2‐PANI/GNP. EP‐nSiO2‐PANI/GNP has enhanced dispersion stability. EP‐nSiO2‐PANI/GNP with a thin nanosilica coating has a good thermal stability. PP nanocomposite with 0.5 wt% filler has excellent antibacterial activity. The electrostatic, free radical, and nanoknife effect antibacterial mechanism. [ABSTRACT FROM AUTHOR]

AbstractFluorinated polyurethaneimide (PUI) electro-optic waveguide polymer with polyurethane and polyimide chain segment structures was synthesized by stepwise polymerization using the synthesized amino ester oligomer pu and imide oligomer pi as monomers. Since the main chain structure of the synthesized PUI had the functionality of both polyurethane and polyimide chain segment structures, it combines the excellent thermal and film-forming properties of polyurethanes and polyimides, as well as lower optical transmission loss in the near-infrared wavelength band. The glass transition temperature (Tg) of PUI was 182 °C, and the 5% heat loss decomposition temperature was 325 °C. The PUI had good optical properties with an optical propagation loss of 1.10 dB/cm and an electro-optic (EO) coefficient (γ33) of 86 pm/V at a wavelength of 1550 nm. A Mach-Zehnder interferometric polymer waveguide EO modulator had been designed and fabricated by using the PUI as a waveguide electro-optic core layer. The prepared polymer waveguide EO modulator showed a good electro-optic modulation response at a wavelength of 1550 nm under an applied 1 kHz sinusoidal modulation signal. The results showed that the synthesized PUI met the performance requirements for the preparation of polymer optical waveguide devices and was a polymer electro-optic waveguide material with good overall performance. [ABSTRACT FROM AUTHOR]

As a key component for wearable electronics, intrinsically stretchable and healable semiconducting polymers are scarce because carrier mobility is often reduced with increasing stretchability and self-healability. Here, we combine stepwise polymerization and thermal conversion to introduce in situ continuous hydrogen bonding sites in a polymer backbone without breaking the conjugation or introducing bulky softer side chains, benefiting the intrachain and interchain charge transport. We demonstrate that a regular sequence structure facilitated the formation of big nanofibers with a high degree of aggregation, providing the loose and porous thin film with simultaneously improved charge transport, stretchability, and self-healability. The mobility of damaged devices can be recovered to 81% after a healing treatment. Fully stretchable transistor based on the designed polymer exhibited a greatly enhanced mobility up to 1.08 square centimeters per volt per second under 100% strain, which is an unprecedented value and constitutes a major step for the development of intrinsically stretchable and healable semiconducting polymers. [ABSTRACT FROM AUTHOR]

Polymer dielectrics play an irreplaceable role in electrostatic capacitors in modern electrical systems, and have been intensively studied with their polarization and breakdown strength (Eb) optimized for high discharged energy density (Ud) at elevated temperatures. Small molecules have been explored as fillers, yet they deteriorate thermal stability of matrix which limits their optimal loading to ~1 wt%. Herein, we develop a polymer blend dielectric consisting of common polyimide and a bifunctional dipolar glass polymer which are synthesized from two small molecule components with wide band-gap and large dipole moment. The bifunctional dipolar glass with large molecular weight not only maintains thermal stability of polymer blends even at a high loading of 10 wt%, but also induces substantial enhancement in polarization and Eb than any of individual components does, achieving an ultrahigh Ud of 8.34 J cm−3 (150 °C) and 6.21 J cm−3 (200 °C) with a charge-discharge efficiency of 90%. The authors develop a polymer blend dielectric consisting of common polyimide and a bifunctional dipolar glass polymer which are synthesized through condensation polymerization of two small molecule components with wide band-gap and large dipole moment. [ABSTRACT FROM AUTHOR]

Poly(ethylene glycol 1,4-cyclohexanedimethylene isosorbide terephthalate) (PEICT) copolymers synthesized from isosorbide (ISB), 1,4-cyclohexanedimethanol (CHDM), ethylene glycol (EG) and terephthalic acid (PTA) via polycondensation are a class of heat-resistant bio-based polyesters. The content of biomass-sourced ISB has an important influence on the various properties of the terpolymers but lacks detailed study. Herein, we synthesized a series of amorphous terpolyesters with different contents of ISB by melt polycondensation of ISB, CHDM, EG and PTA in a 30 L reactor, and investigated the effect of ISB content on the thermal, mechanical, optical and rheological properties. As the content of ISB increasing, the complex viscosities of terpolyesters were increased and the intrinsic viscosities were decreased. The tensile strength was increased from 45.1 MPa for poly(ethylene glycol 1,4-cyclohexanedimethylene terephthalate) (PCTG)to 48.1 MPa for PEI13.2CTandthe Tg was increased from 83.5 °C for PCTG (ISB 0 mol%) to 98.8 °C for PEI13.2CT (ISB 13.2 mol%). All the values of Td,5%, and Td,max of the terpolyesters were higher than 395 °C and 425 °C. [ABSTRACT FROM AUTHOR]

L‐lactide (LA) is polymerized with ethyl L‐lactate or trifluoroethanol as initiators (LA/In = 30/1), and the resulting poly(L‐lactide) esters are acetylated with acetic anhydride. The acetylated PLA esters are mixed with SnOct2, dibutyltin bis(4‐chlorophenoxide), or dibutyltin bis(pentafluorophenoxide) in solution and crystallized at 120 °C. The doped crystals are annealed at 140 °C or at 160 °C for 7, 14, and 28 days, and the chemical modifications that occurred in the solid state are monitored by matrix‐assisted laser desorption/ionization time‐of‐flight (MALDI TOF) mass spectrometry, gel permeation chromatography (GPC), and differential scanning calorimetry (DSC) measurements. All catalysts promoted polycondensation, while no significant formation of cycles is observed. However, in the presence of SnOct2, disproportionation of chains occurred upon annealing at 120 or 140 °C, and crystallites consisting of extended chains with Mn values ≈3500 – 3600 and low dispersities (Ð < 1.5) are formed. [ABSTRACT FROM AUTHOR]

The production and application of poly(butylene succinate) (PBS) still face challenges such as high production costs, insufficient toughness, and slow biodegradation. This study utilizes the ring‐opening condensation polymerization method to prepare PBS copolyesters using succinic anhydride (SAA) and 1,4‐butanediol (BDO) as raw materials, with 20 moL% different lengths of linear‐chain diols as third monomers (carbon numbers are 3, 5, 6, 8, 9,10, and 12). Both PBS and its copolyesters exhibit high weight average molecular weights (18.8 × 104–26.1 × 104 g moL−1), much higher than those obtained through the traditional conventional direct esterification method. Incorporating the third monomer reduces the glass transition temperature (Tg), crystallinity, and melting point (Tm) of the copolyesters. As the chain length of the third monomer increases, the copolyesters show improved toughness, with the elongation at break and notch impact strength of poly(butylene succinate‐ran‐dodecylene succinate) (P(BS‐ran‐DoS)) increasing from 374.1% and 5.6 KJ m−2 of PBS to 723.2% and 64.8 KJ m−2, respectively. The degradation rate of the copolyesters modified with short‐chain diols increases significantly, and as the chain length of the third monomer increases, the degradation rate of the copolyesters slows down. Therefore, the selection of the third monomer can be used to adjust the properties of the polymer. [ABSTRACT FROM AUTHOR]

Carbon hollow microspheres (CHM) have been heralded as a seminal material, manifesting a multifaceted utility in domains such as catalysis, adsorption, energy storage, and conversion. In this study, the present investigation delves into the fabrication of lignin-formaldehyde resin (LFR) carbon hollow microspheres (LFR-CHM) via the nuanced methodologies of spray drying and subsequent carbonization. The precursor for CHM, a thermosetting LFR, was crafted via polycondensation in an alkaline milieu. Precision-tuning of the spray drying parameters enabled the realization of LFR hollow microspheres, characterized by particle diameters spanning 3.37 μm–24.4 μm, and shell thickness between 0.25 μm and 4.0 μm. Adjusting the inlet temperature from 110 to 180 °C resulted in LFR hollow microspheres with varying bulk densities from 0.31 g/cm3 to 0.49 g/cm3. The microporous structure of the LFR-CHM shell exhibited a malleable specific area and pore dimensionality, intricately tethered to the carbonization thermal gradient. Furthermore, changes in crystallinity and chemical bonds of LFR-CHM were noted during carbonization process. Significantly, the residual weight of LFR-CHM reached 52 % after carbonization at 800 °C, underscoring the benefits of using thermosetting lignin-formaldehyde resin as a CHM precursor. [ABSTRACT FROM AUTHOR]

Dendrimers, distinguished by their mono-dispersed globular or spheroid macromolecular structures with repeated branches, exhibit unique and desirable characteristics that set them apart from other polymers. These characteristics include their nanoscopic size, precise control over molecular structure, low polydispersity index, water solubility, exceptional physicochemical stability, self-assembly capabilities, polyvalency, chemical stability, electrostatic interactions, solubility, and minimal cytotoxicity. Dendrimers are prepared from monomers using either divergent or convergent step-growth polymerization. Dendrimers have the ability to reduce the toxicity of medications while enhancing their effectiveness. This review will delve into various types of dendrimers such as poly (amidoamine) dendrimers, peptide dendrimers, smart dendrimers, polyethylene glycol dendrimers, poly (propylene imine) dendrimers, polyester dendrimers, Janus dendrimers, and etc. in the field of drug delivery and gene delivery systems that utilize them. Dendrimer-drug conjugates offer numerous benefits over conventional drug carriers, such as enhanced drug uptake by the tumor, reduced systemic toxicity issues, and increased antitumor activity of the administrated medications. To achieve this objective, the authors utilized the Science Direct, PubMed, and Scopus databases to acquire the information, evaluating references individually, extracting essential details, and assessing the quality of the included studies. [ABSTRACT FROM AUTHOR]

Keeping the principles of sustainability in view, this work explores the extraction of indene from pyrolysis oil—a complex by-product of the Ustyurt Gas-Chemical Complex—and its transformation into a novel cationite, highlighting sustainable approaches in chemical engineering and material science. Utilizing advanced analytical techniques, including thermogravimetric analysis (TG), chromato-mass spectrometry, and Fourier-transform infrared spectroscopy (FT-IR), indene was efficiently isolated and characterized. The indene extracted exhibited a principal ion peak at a molecular mass (m/z) of 117.0, confirming its purity and potential for further applications. Following extraction, indene underwent sulfonation and polycondensation with 35% formalin under specific conditions (100–110°C, 30–40 atm), resulting in a cationite with a yield of 71%. This synthesized IESA (indene-based sulfonated aromatic cation exchanger), demonstrated significant chemical–physical properties when compared to commercial equivalents, such as a moisture content significantly lower than the KU-2-8 (29.4% vs. 48–58%), and a dynamic exchange capacity (DEC) competitive with industry standards (472 mmol/m3 vs. 500–520 mmol/m3). The study not only showcases the potential of pyrolysis oil as a valuable feedstock for producing high-value chemical products, but also advances the development of new materials from industrial by-products. [ABSTRACT FROM AUTHOR]

The application and promotion of biodegradable plastics are hindered by the imbalance between their mechanical and degradation performance imbalance, as well as high costs. Herein, a series of poly(ethylene adipate‐co‐terephthalate) (PEAT) copolyesters with excellent mechanical and degradation properties are synthesized by one‐step melt polycondensation. The influence of the proportion of aliphatic groups in the molecular chain on the structure and properties, especially the degradation performance, of the copolyesters was studied. The molecular chain flexibility and degradability of PEAT increases with increasing of adipic acid content and decreasing of ET fragment length (LET). The comprehensive mechanical properties of PEAT60 can be comparable to traditional packaging material poly(butylene adipateco‐terephthalate) (PBAT). The degradation performance of PEAT can be adjusted the molecular chain structure. PEAT with LET < 3 exhibit degradation performance, and PEAT with LET < 2.2 exhibit significant degradation acceleration. The excellent mechanical and degradable properties of PEAT copolyester make it expected to be used in degradable packaging and other fields to help solve plastic pollution, while its lower cost will aid in the promotion of degradable materials. [ABSTRACT FROM AUTHOR]

The energy sector has demonstrated significant enthusiasm for investigating post‐combustion CO2 capture, storage, and separation. However, the practical application of current porous adsorbents is impeded by challenges related to cost competitiveness, stability, and scalability. Intregation of heteroatoms in the porous organic polymers (POPs) dispense it more susceptible for CO2 adsorption to attenuate green house gases. In this regard, two hydroxy rich hypercrosslinked POPs, namely Ph/Tt‐POP have been developed by one‐pot condensation polymerization using a facile synthetic strategy. The high surface areas of both the Ph/Tt‐POP (1057 and 893 m2g−1, respectively), and the heteroatom functionality in the POP framework instigated us to explore our material for CO2 adsorption study. The CO2 uptake capacities in Ph/Tt‐POP are found to be 2.45 and 2.2 mmol g−1, at 273 K respectively. Further, in‐situ static 13C NMR experiment shows that CO2 molecules in Tt‐POP appear to be less mobile than those in Ph‐POP which probably due to the presence of triazine functional groups along with high abundant −OH groups in the Tt‐POP framework. An in‐depth study of the CO2 adsorption mechanism by density functional theory (DFT) calculations also shows that CO2 adsorption at the cages formed by two benzyl rings represents the most stable interaction and CO2 molecule is more favorably adsorbed on the Ph‐POP with the more negative interaction energies values compared to that of Tt‐POP. Further, Non‐covalent interaction (NCI) plot reveals that CO2 molecules adsorb more on the Ph‐POP than Tt‐POP, which can be explain by hydrogen bond formation in case of Tt‐POP repeating units turning aside CO2 molecule to interact with the Ph component. Overall, our present study reflects the comprising effects of surface area of the solid adsorbents as well as their functionality can be beneficial for developing efficient hypercrosslinked porous polymers as solid CO2 adsorbent. [ABSTRACT FROM AUTHOR]

Ladder-like structured poly(phenyl-co-glycidoxypropyl) silsesquioxanes with different ratios of phenyl to glycidyl group (LPS64 and LPS 82) were synthesized using simple hydrolysis reaction followed by condensation polymerization of phenyltrimethoxysilane (PTMS) and (3-glycidyloxypropyl)trimethoxysilane (GPTMS). Two series of hybrid polyimide composites (PI/LPS64 and PI/LPS82) with different contents of LPS (10, 20, and 30 wt%) were prepared by the chemical reaction of epoxy groups in LPS64 or LPS82 and the terminal amine groups in poly(amic acid). The dielectric constant (k) of hybrid PI composites (k = 1.3) was lower than that of pure polyimide (k = 2.9) and the degree of roughness was increased according to the increase of LPS contents. The dispersion of LPS in the PI matrix was improved due to the chemical bonding between LPS and PI. The thermal stability of PI/LPS82 was higher than that of PI/LPS64 due to the enhanced π-π stacking between PI matrix and LPS82 with more phenyl groups as compared to LPS64. [ABSTRACT FROM AUTHOR]

To improve the comprehensive properties of polybutylene furandicarboxylate (PBF), 2,5‐furandicarboxylic acid (2,5‐FDCA), and aliphatic chain diol 1,8‐octanediol and 1,4‐butanediol were used as monomers to synthesize a series of bio‐based polybutylene glycol‐octanediol 2,5‐furandicarboxylate (PBOF). The results showed that the chemical composition of PBOF could be controlled through the molar ratio of monomers. Compared with PBF, as the proportion of octanediol segments gradually increased, PBOF could gradually transform from semi‐crystalline thermoplastic to amorphous form, and the glass transition temperature (Tg) gradually decreased. The crystallization ability reduced but a part of the crystal area was still retained. The copolyesters still has a decomposition temperature above 370°C, indicating excellent thermal stability. The introduction of the octanediol segment significantly improved the tensile mechanical properties and flexibility of the POBF copolyester. These meet the requirements for the preparation of bio‐based engineering plastics. The water absorption rate of PBOF showed that it may have certain degradable potential. PBOF copolyesters have potential application prospects in bio‐based medical plastics and biodegradable packaging polymer materials after copolymerization modification. [ABSTRACT FROM AUTHOR]

As the demand for sustainable polymers increases, most research efforts have focused on polyesters, which can be bioderived and biodegradable. Yet analogous polythioesters, where one of the oxygen atoms has been replaced by a sulfur atom, remain a relatively untapped source of potential. The incorporation of sulfur allows the polymer to exhibit a wide range of favorable properties, such as thermal resistance, degradability, and high refractive index. Polythioester synthesis represents a frontier in research, holding the promise of paving the way for eco‐friendly alternatives to conventional polyesters. Moreover, polythioester research can also open avenues to the development of sustainable and recyclable materials. In the last 25 years, many methods to synthesize polythioesters have been developed. However, to date no industrial synthesis of polythioesters has been developed due to challenges of costs, yields, and the toxicity of the by‐products. This review will summarize the recent advances in polythioester synthesis, covering step‐growth polymerization, ring‐opening polymerization (ROP), and biosynthesis. Crucially, the benefits and challenges of the processes will be highlighted, paying particular attention to their sustainability, with the aim of encouraging further exploration and research into the fast‐growing field of polythioesters. [ABSTRACT FROM AUTHOR]

In this paper, the polycondensation kinetics of bio-based semi-aromatic high temperature polyamide PA10T/1010 was studied in a micro high-temperature and high-pressure reactor. The polycondensation experiment of PA10T/1010 salt solution with temperature of 235 ℃-295 ℃ and initial water content of 5 wt%-25 wt% was carried out. The change of end group content in the reaction process was investigated, and the relationship between polymer equilibrium molecular weight and temperature and water content was explored. The results showed that the end group concentration decreased rapidly at the beginning of the reaction, approached equilibrium after a period of time, and the higher the temperature, the higher the initial water content and the lower the equilibrium molecular weight, indicating that the polycondensation of PA10T/1010 was an exothermic reaction; on this basis, a kinetics model of polycondensation reaction was established based on the literature model, it was considered that the polycondensation reaction is an acid catalyzed third-order reaction, and the effects of temperature and water content on the equilibrium and rate of polycondensation reaction can be investigated; The kinetics model of polycondensation reaction was obtained, and the calculated results of the model were basically consistent with the experimental values. [ABSTRACT FROM AUTHOR]

In this study, a series of aromatic hyperbranched polyester (Ar.HBPs) of different generations (G1-G4) were synthesized using one-shot solution poly condensation, and their structural, physical, thermal and optical properties were studied in detail. The formation of aromatic ester bond in the product was confirmed using spectral analyses (FTIR and NMR). Ar.HBP reaction kinetics was studied from the changes in acid-to-ester band using FTIR and the optimal reaction time is around 21 h (G1), 26 h (G2), 29 h (G3) and 31 h (G4). DSC thermal data revealed their glass transition temperature at around 120 °C. From TGA data, thermal degradation (T10, oC) of Ar.HBPs started at around 216 °C (G1), 230 °C (G2), 241 °C (G3) and 243 °C (G4). MALDI-TOF investigation confirmed the chemical structure and molecular weight of the synthesized Ar.HBPs. Their optical property was revealed in the UV region by the existence of a broad absorption peak at 580 nm. From the aforementioned characterization studies, the synthesized Ar.HBPs supported the formation of a highly branched structure and an improvement in thermal stability with increasing HBP generations from G1 to G4. Ar.HBP (G1-G4) synthesis reported in this work will serve as a guideline for understanding their reaction kinetics, and the influence of their final properties on applications such as energy materials, optoelectronic materials and devices. [ABSTRACT FROM AUTHOR]

Mercury, a highly toxic metal and pollutant, poses a significant risk to human health and the environment. This study describes the synthesis of a new nitrogen-doped heteroaromatic hyper-crosslinked polyamine (HCPA) via the polycondensation of 2,6-diaminopyrazine and tris(4-formylphenyl)amine for the efficient removal of mercury ions from aqueous solutions. The HCPA polymer was characterized by solid-state 13C-NMR and FT-IR spectroscopy. A powder X-ray diffraction and thermogravimetric analysis showed that the polymer was semicrystalline in nature and stable up to 500 °C. Adsorption isotherms indicated that mercury adsorption occurred via mono- and multilayer adsorption by HCPA, as depicted by the Langmuir, Freundlich, and Redlich–Peterson isotherm models, with a maximum adsorption capacity of qm = 333.3 mg/g. Adsorption kinetic models suggested that the adsorption process was fast and effective, reaching equilibrium within 20 min. Thermodynamics of the adsorption process revealed that it was endothermic and spontaneous in nature due to the positive ΔH0 of 48 kJ/mol and negative ΔG0 values of −4.5 kJ/mol at 293 K. Wastewater treatment revealed 98% removal of mercury indicating the selective nature of HCPA. Finally, HCPA exhibited excellent performance and regeneration up to three cycles, demonstrating its great potential as an adsorbent for environmental remediation applications. [ABSTRACT FROM AUTHOR]

Stepwise photopolymerization is a miraculous strategy modulating the polymer skeleton and electro-optical properties of light modulators based on liquid crystal/polymer composites. However, owing to the indistinct polymerization mechanism and curing condition discrepancy, the required polymer structures and electro-optical properties are hard to be controlled precisely. Herein, a novel polymer-stabilized liquid crystal film based on acrylate/epoxy resin is proposed, fabricated and the relationships between preparation process, polymer content, polymer morphology and electro-optical properties are studied. The in-situ photopolymerization of acrylate/epoxy resin liquid crystalline polymer is fulfilled using cation photo-initiator UV 6976. The distinct photopolymerization speed between acrylate and epoxy resin benefits the polymer morphology control, and with accurate containment of the polymerization process and polymer composition, the superior electro-optical properties at a higher polymer content are acquired. The polymer morphology and electro-optical properties are influenced by the polymer content and mass ratio between acrylate and epoxy resin. The best electro-optical properties among samples are attained by controlling the mass ratio between acrylate and epoxy resin to 1:1, integrating higher densities of scattering centers and lower anchoring effect. With higher polymer content, the strategy of increasing the mass ratio of E6M benefits the improvement of E-O properties for alleviating polymer density. This work provides insights to stepwise polymerization of liquid crystalline monomers and offers a fancy strategy for the preparation of novel liquid crystal dimming films. [ABSTRACT FROM AUTHOR]

An electroactive polyazomethine was prepared directly on a transparent electrode by the polycondensation of bis(triphenylamine) dialdehyde and its complementary methoxytriphenylamine diamine. The spray-and-bake method of coating the electrode for preparing electrochromic layers could be upscaled to prepare working devices larger than standard test devices. The film prepared by thermally annealing the complementary monomers was both electroactive and switched its color with an applied potential. The yellow electrochromic polyazomethine could be electrochemically oxidized reversibly to obtain a blue film. The electrochromic test device fabricated from the polyazomethine was operated upwards of 1 h for performance assessment. The electrochromic response times of the electrochromic device were ca. 3.3 and 1.2 s for the coloration and bleaching, respectively. The upscaled device prepared by the straightforward coating approach had consistent metrics with the small-area test device. [ABSTRACT FROM AUTHOR]

In recent years, thermoset elastomers, particularly polyesters derived from the polycondensation of glycerol and non-toxic diacids, have garnered significant interest. This study focuses on the synthesis of poly(glycerol-co-diacids) polymers using varying molar ratios of glycerol (G), sebacic acid (S), and succinic acid (Su). Seven distinct ratios were investigated (PGS (1:1), PGSSu (1:0.9:0.1), PGSSu (1:0.8:0.2), PGSSu (1:0.5:0.5), PGSSu (1:0.2:0.8), PGSSu (1:0.1:0.9) and PGSu (1:1)). The resulting polymers were analyzed using Fourier-transform infrared spectroscopy (FTIR), thermogravimetric analysis (TGA), dynamic mechanical analyses (DMA), tensile tests, scanning electron microscopy (SEM), gel fraction and degree of swelling determination. Among the synthesized polymers, PGS (1:1) and PGSu (1:1) exhibited superior mechanical robustness than the polymers obtained by mixing diacids. The results show that the incorporation of succinic acid in the synthesis of the polymers progressively led to rougher surfaces and a reduction in thermal resistance compared to PGS (1:1). PGSu (1:1) showed the highest surface roughness and the lowest thermal resistance. The glass transition temperature (Tg) for these elastomers ranged from − 30 °C to 30 °C. Additionally, higher ratios of succinic acid led to increased polymer density and less degree of swelling. The gel fraction of these polymers ranged from 70 to 95%. PGS (1:1) with the lowest and PGSu (1:1) with the highest gel fraction, respectively. [ABSTRACT FROM AUTHOR]

Recently, there has been growing interest in materials that combine the advantages of glass and polymer materials. Such a combination results in a kind of hybrid glass-polymer optics that meets the requirements for high-quality imaging in various environmental conditions. So far, the literature on these materials is quite scarce. This article is an attempt to review the most important reports on the topic of available polymers with optical properties, dividing them into groups, i.e. synthetic optical polymers (including polymethylmethacrylate, polyethylene terephthalate, polypropylene, cyclic olefin copolymers and polyolefin elastomers) and biopolymers (including polylactide and gelatin). A separate place and chapter is given to transparent CR-39 plastic and the issue of individual dosimetry for radon detection. Moreover, testing methods for measuring the most important optical properties of polymers and their major applications are briefly discussed.

Over the past two decades, hyperbranched polymers (HBPs) have been an interesting material for many researchers due to their unique physical and chemical properties. The purpose of this article is to review hyperbranched polymers, their history, their synthesis methodologies and their main applications. It was found that the first hyperbranched polymer was synthesized in the 19th century by Berzelius and since then several researchers have prepared other hyper-branched polymers. In addition, there are many methods for the synthesis of hyperbranched polymers, both simple and complex. There are also several applications of these polymers, ranging from construction and building materials to biomaterials. The structure of polymers is responsible for a wide range of material properties. These properties allow the use of polymer materials in the design of building and industrial structures.

The paper presents the photomechanical effect generated in new azo side-chain polyimides synthesized through a post-functionalization strategy involving the Mitsunobu reaction. Prepared azo polyimide foils were irradiated by a 405 nm diode-laser beam (intensity, I = 100 mW/cm2; polarization, Eǀǀx) for the generation of the photomechanical effect. Despite the low content of azo chromophore (substitution of the hydroxyl group was in the range of 7–35%) and thick cantilevers (thickness ~35 μm), bending angles were in the range of 30–40°. Thermal unbending was not observed for 12 months after turning off the excitation light. Our investigation showed that, despite the low content of azo chromophore, it is possible to achieve photodeformation under polarized light. To the best of our knowledge, this is the first example of the photomechanical response of azo pyridine polymers.

Polythiophenes are the most appealing donor materials in organic solar cells (OSCs) due to their simple chemical structures. However, the top‐performance polythiophenes are typically synthesized via Stille polycondensation, which is problematic due to significant toxicity and poor atom economy. By contrast, direct arylation polycondensation (DArP) is an eco‐friendly, and atom‐efficient alternative for synthesizing conjugated polymers, while the best efficiency for DArP‐derived polythiophenes is below 12%. This study reports a series of polythiophene‐based donors synthesized via DArP. Among these, PT4F‐Th reaches a power conversion efficiency (PCE) of 16.4%, which not only matches the current record for polythiophene‐based donor materials, but also marks the highest PCE achieved by DArP‐derived donors to date. The superior performance of PT4F‐Th is largely attributed to its optimal temperature‐dependent aggregation behavior and moderate miscibility with acceptors, along with the highest crystallinity among the candidates, resulting in the most favorable blend film morphology. This study underscores the significant potential of DArP‐derived polythiophenes in developing high‐performance and eco‐friendly OSCs. [ABSTRACT FROM AUTHOR]

The introduction of reactive groups into thermoplastic tougheners can overcome the phase separation problem between conventional thermoplastic resins and thermosetting resins, thereby improving the compatibility between the two phases and significantly enhancing the materials' toughness. In this study, a series of polyaryletherketone (RPEK‐C) copolymers with a molecular backbone containing reactive propenyl and controllable groups are prepared. Through blending different amounts and different reaction group contents of thermoplastic resins into the N,N'‐（4,4'‐methylenediphenyl) dimaleimide(BDM)/2,2′‐diallylbisphenol A (DABPA) system, all of them show a homogeneous phase instead of separation phase after curing, and the impact toughness is improved to different degrees. When RPEK‐C‐10 with 7.5 phr is added, the impact strength of the toughened BDM/DABPA can be increased up to 172.5%. Compared with the nonactive PEK‐C, active groups of RPEK‐C can react with BDM, playing a role in "anchoring" the thermoplastic molecular chains. The toughening mechanism of BDM/DABPA with RPEK‐C participating is discussed. This study shows that polyaryletherketones with functional active group have great potential application in high‐end toughening fields. [ABSTRACT FROM AUTHOR]

Comprehensive Summary: Porous organic polymers (POPs) have attracted great attention in past decades. Although diverse functional POPs have been developed, multistimuli‐responsive POPs with excellent aggregate‐state luminescence together with good chiroptical properties have rarely been reported. Herein, two pairs of Salen‐type enantiomeric POPs with multistimuli‐responsive luminescence and chiral features were designed and synthesized by facile polycondensation reactions between polyfunctional aggregation‐induced emission luminogen (AIEgen)‐containing salicylaldehyde derivatives and chiral diamines. With Salen units in polymer backbones as tetradentate ligands, a series of POP‐metal complexes were further prepared. The obtained POPs and metal complexes show good porosity, high thermal stability, and obvious circular dichroism signals. Moreover, benefiting from the coexistence of AIEgen and Salen units in polymer structures, these POPs exhibit excellent luminescence performance in aggregate states and tunable fluorescence behaviors in response to external stimuli of Zn2+ ion, mechanical forces, organic solvent, and acids. Due to the dynamic feature of Schiff base C=N bonds, the present POPs can efficiently undergo hydrolysis reactions under strong acidic conditions to reproduce the AIEgen‐ containing monomers, and such an acid‐induced degradation process can be directly visualized and dynamically monitored via fluorescence variation. These properties collectively make the POPs candidate materials for applications in heterogeneous asymmetric catalysis, fluorescence sensing, biomedicine, etc. [ABSTRACT FROM AUTHOR]

Recently, renewable bio‐based materials have received more and more attention due to environmental issues such as global warming and ecosystem destruction. In the present work, a series of isosorbide‐based bioelastomers poly(isosorbide carbonate‐co‐butanediol aliphatic esters)s (PICBAs) are synthesized by a facile and economical two‐step melt polycondensation. Due to the slightly self‐crosslinking reaction of isosorbide, PICBAs exhibit excellent tensile strength and self‐healing ability, the mechanical properties of PICBAs can recover over 95% after 48 h under room temperature. In addition, PICBAs can stick different substances, such as glass, rubber, plastic, and stones, and show better adhesive performance than 3M commercially available double‐sided tape. Consequently, isosorbide‐based bioelastomers PICBAs are of great potential to be used as environmentally friendly pressure‐sensitive adhesives (PSA) in the future. [ABSTRACT FROM AUTHOR]

In this work, a series of nickel-containing samples of carbon xerogels (Ni@CX) were synthesized by introducing nickel acetate into a solution of precursors (resorcinol and formaldehyde), joint polycondensation, and subsequent pyrolysis in an atmosphere of argon. The samples were tested in the selective hydrogenation reaction of 1,3-butadiene. It was shown that catalysts prepared without the addition of complexing agents contained nickel nanoparticles (4–7 nm) stabilized in a carbon matrix. The Ni@CX catalyst made it possible to achieve a selectivity of 93% for butenes at a conversion of 94% and a temperature of 200°C, while the selectivity for the formation of butenes in the presence of an impregnated reference sample was lower than 1%, although it provided a conversion of 100% already at 75°C. It was supposed that the selectivity of catalysts prepared by the joint synthesis increased due to the blockage of nonselective catalytic sites by carbon of the support. [ABSTRACT FROM AUTHOR]

In this study, 4-biphenyl-3,5-diaminobenzoate (E- m -PDA) was synthesized by three steps using 3,5-dinitrobenzoic acid as a starting material. Two series of colorless polyimides (CPIs) PI-(1a-1d) and PI-(2a-2d) were prepared by traditional two-step polycondensation of m -phenylenediamine (m -PDA) based diamines with different pendant groups (-H, CF3, COOH and biphenyl ester) with aromatic dianhydrides BPADA and 6FDA, respectively. All of the prepared CPIs exhibited high thermal stability with 5% weight loss at temperatures ranging from 428 to 539°C in nitrogen, and glass transition temperatures (T gs) ranging from 228 to 332°C. These PI films displayed a UV-vis absorption cut-off wavelength at 338–376 nm and transparency of 76%–89% at a wavelength of 450 nm. Both series of colorless PI films also showed low birefringence values of 0.0021–0.0100. In addition, the optical retardations of these CPIs were extremely low (48–220 nm), indicating low optical anisotropy of these CPI films. Colorless PI film PI-2d prepared based on E- m -PDA and 6FDA had good comprehensive properties of low birefringence (∆ n of 0.0064), high T g (319°C) and excellent transparency (T 450 of 88%). [ABSTRACT FROM AUTHOR]

N‐methyl‐2‐pyrrolidone‐soluble ferrocene‐containing polychalcones, which are promising as a platform for the formation of ferromagnetic coatings after pyrolysis in an inert atmosphere is synthesized through the polycondensation of isophthalic aldehyde and 1,1′‐diacetylferrocene by the Claisen–Schmidt reaction. The structure and the molecular weight distribution of the polychalcones is characterized by NMR, IR spectroscopy, and size exclusion chromatography. It is shown that the formation of polychalcones is accompanied by chain branching via the Michael reactions and the aldol‐croton condensation. The structure of the linear fragments of the polychalcone chains is simulated with a tailored low‐molecular model compound, that is 1,3‐bis(3‐ferrocenyl‐1‐propen‐2‐one)benzene, which is characterized by the NMR and IR spectroscopy as well as the X‐ray diffraction analysis. The obtained results indicate an increasing tendency for polychalcone chain branching with the temperature growth during the Claisen–Schmidt reaction. The weight loss and the increase in magnetization under the conditions of pyrolysis of polychalcones at different temperatures is studied. The assumptions regarding the possible mechanisms of thermal destruction of ferrocene‐containing macromolecules are put forward. [ABSTRACT FROM AUTHOR]

The single‐unit monomer insertion (SUMI), derived from living/controlled polymerization, can be directly functionalized at the end or within the chain of polymers prepared by living/controlled polymerization, offering potential applications in the preparation of polymers with complex architectures. Many scenarios demand the simultaneous incorporation of monomers suitable for different polymerization methods into complex polymers. Therefore, it becomes imperative to utilize SUMI technologies with diverse mechanisms, especially those that are compatible with each other. Here, we reported the orthogonal SUMI technique, seamlessly combining radical and cationic SUMI approaches. Through the careful optimization of monomer and chain transfer agent pairs and adjustments to reaction conditions, we can efficiently execute both radical and cationic SUMI processes in one pot without mutual interference. The utilization of orthogonal SUMI pairs facilitates the integration of radical and cationic reversible addition‐fragmentation chain transfer (RAFT) polymerization in various configurations. This flexibility enables the synthesis of diblock, triblock, and star polymers that incorporate both cationically and radically polymerizable monomers. Moreover, we have successfully implemented a mixing mechanism of free radicals and cations in RAFT step‐growth polymerization, resulting in the creation of a side‐chain sequence‐controlled polymer brushes. [ABSTRACT FROM AUTHOR]

Thiophene‐based conjugated polymers show a unique position in the constantly expanding variety of conjugated polymers because of their outstanding optical and conductive characteristics. during the past few decades, many researchers have made significant contributions by developing new methods to create more effective materials for electronic applications. Employing one‐pot Suzuki polycondensation, a unique series of structurally condensed multicolumn/multilayer 3D polymers and oligomers have been developed and synthesized in this research. Polymers were produced with moderate to excellent yields in all instances, as examined by GPC and 1H‐NMR. The results from experiments of optical rotation and AIE investigation, show that the current work will benefit materials research and applications. [ABSTRACT FROM AUTHOR]

Ring‐opening polymerization (ROP) offers a striking solution to solve problems encountered in step‐growth condensation polymerization, including precise control over molecular weight, molecular weight distribution, and topology. This has inspired our interest in ROP of cycloalkanes with an ultimate goal to rethink polyolefins, which clearly poses a number of challenges. Practicality of ROP of cycloalkanes is actually limited by their low polymerizability and elusive mechanisms which arise from significantly varied ring size and non‐polar C−C bonds in monomers. In this work, by using Lewis acid/Brønsted base/C(sp3)‐H initiator system previously developed in our laboratory, we focus on cyclobutanes and explore the positional and electronic effects of substituents on the ring, namely electron push‐pull effect, in promoting controlled polymerization to afford densely functionalized poly(cyclobutanes), as well as catalytic degradation of obtained polymers for upcycling. More importantly, experiments and DFT calculations unveil considerable population of Lewis‐acid‐induced thermostabilized 1,4‐zwitterions, which distinguish cyclobutanes from cyclopropanes and others. All these findings would shed light on catalytic synthesis and degradation of saturated all‐carbon main‐chain polymers, as well as small molecule transformations of cyclobutanes. [ABSTRACT FROM AUTHOR]

Polyvinylpyrrolidone (PVP) exhibits remarkable qualities; owing to the strong affinity for water of its pyrrolidone group, which enhances compatibility with aqueous systems, it is effective for stabilizing, binding, or carrying food, drugs, and cosmetics. However, coating the surface of polymeric films with PVP is not practical, as the coatings dissolve easily in water and ethanol. Poly(silane–pyrrolidone) nano/microparticles were prepared by combining addition polymerization of methacryloxypropyltriethoxysilane and N-vinylpyrrolidone, followed by step-growth Stöber polymerization of the formed silane–pyrrolidone monomer. The silane–pyrrolidone monomeric solution was spread on oxidized polyethylene films with a Mayer rod and polymerized to form siloxane (Si-O-Si) self-cross-linked durable anti-fog thin coatings with pyrrolidone groups exposed on the outer surface. The coatings exhibited similar wetting properties to PVP with significantly greater stability. The particles and coatings were characterized by microscopy, contact angle measurements, and spectroscopy, and tested using hot fog. Excellent anti-fogging activity was found. [ABSTRACT FROM AUTHOR]

Herein, a cationic hydrogel microsphere (CHMS) was prepared by inverse suspension polymerization and freeze‐drying and was applied to the adsorptive removal of hexavalent chromium (Cr(VI)) from aqueous solution. Morphological characterization shows that there are lots of folds and pores on the surface of CHMS with a unique petal‐like appearance. According to the chemical structure analysis, CHMS contains plenty of functional groups such as amine and hydroxyl groups. These features give CHMS a larger specific surface area, faster adsorption rate, and higher adsorption capacity than the conventional cationic hydrogel microparticle (CHMP) adsorbent. The adsorption of Cr(VI) in water by CHMS is mainly based on the combination of electrostatic adsorption and redox reaction, with the electrostatic interaction between the protonated amine and Cr(VI) serving as the predominant adsorption mechanism. Experimental results reveal that CHMS can efficiently remove Cr(VI) from simulated wastewater in both batch and continuous adsorption modes, which is primarily due to its distinctive surface morphology and rich functional groups. Furthermore, the common coexisting metal ions in Cr(VI)‐containing wastewater have no substantial negative influence on the adsorption. Therefore, it can be concluded that CHMS has a promising application prospect in the treatment of Cr(VI)‐containing wastewater. [ABSTRACT FROM AUTHOR]

Two organo‐soluble polyimide (PI) resins were prepared from a tricyclic fluoro‐containing dianhydride 9,9‐bis(trifluoromethyl)xanthene‐2,3,6,7‐tetracarboxylic dianhydride (6FCDA) and aromatic diamine of 2,2‐bis[4‐(4‐aminophenoxy)phenyl]hexafluoropropane (BDAF) for PI‐IIa and 1,3‐bis(3‐aminophenoxy)benzene (133APB) for PI‐IIb, respectively. For comparison, two analogous PIs were prepared from 4,4′‐(hexafluoroisopropylidene)diphthalic anhydride (6FDA) and the same diamines to afford PI‐Ia (6FDA‐BDAF) and PI‐Ib (6FDA‐133APB), respectively. Incorporation of the rigid and planar xanthene units in the 6FCDA‐PIs obviously decreased the solubility of the resins in organic solvents. Flexible and tough PI films were fabricated from the PI solutions in N,N‐dimethylacetamide (DMAc). The PI films derived from the rigid and planar 6FCDA dianhydride exhibited obviously enhance thermal stability, and high‐temperature dimensional stability. For example, PI‐IIa (6FCDA‐BDAF) showed the glass transition temperature (Tg) and coefficient of linear thermal expansion (CTE) values of 311.5°C and 50.5 × 10−6/K, respectively, which were all superior to those of the PI‐Ia counterpart (Tg = 264.6°C; CTE = 55.4 × 10−6/K). In addition, the 6FCDA‐PI films maintained the intrinsically excellent optical transparency of the fluoro‐containing PI films and showed the comparable optical properties to those of the 6FDA‐PI films. As for the properties highly related to the space applications, all the PI films exhibited low solar absorptivity (α) values of 0.18–0.20 and the good thermal emissivity (ε) values in the range of 0.68–0.70. PI‐Ia (6FDA‐BDAF) and PI‐IIa (6FCDA‐BDAF) films showed the similar atomic oxygen erosion behaviors with the standard Kapton® type of PI film derived from pyromellitic dianhydride (PMDA) and 4,4′‐oxydianiline (ODA). [ABSTRACT FROM AUTHOR]

The traditional batch synthesis of liquid rubber faces issues such as low monomer polymerization concentration, poor uniformity of the reaction system, and inadequate heat dissipation, resulting in an unsatisfactory synthesis efficiency. This study presents a method for the rapid and efficient synthesis of high vinyl 1,2‐polybutadiene liquid rubber using butadiene as the monomer and n‐butyllithium as the initiator. By applying continuous flow microchannel reactors, the limitation of traditional synthesis method can be overcome. The addition of a modifier in the raw material promotes the formation of high vinyl structure. The preparation of liquid rubber requires the addition of a large amount of metal lithium initiator. However, for aerospace sealants, there is a requirement for low metal ion content. To address this, we employed different methods to reduce the metal ion content in the liquid rubber and increase its purity. Ultimately, we achieved the synthesis of high‐purity polybutadiene liquid rubber with 1,2‐vinyl content exceeding 88%, narrow molecular weight distribution, and tunable molecular weights. This research will provide technical guidance for the industrial application of polybutadiene synthesis in continuous flow microchannel reactors. [ABSTRACT FROM AUTHOR]

Poly(ethylene terephthalate) (PET), extensively employed in bottles, film, and fiber manufacture, has generated persistent environmental contamination due to its non‐degradable nature. The resolution of this issue requires the conversion of waste PET into valuable products, often achieved through depolymerization into monomers. However, the laborious purification procedures involved in the extraction of monomers pose challenges and constraints on the complete utilization of PET. Herein, a strategy is demonstrated for the polymer‐to‐polymer upcycling of waste PET into high‐value biodegradable and programmable materials named PEXT. This process involves reversible transesterifications dependent on ester bonds, wherein commercially available X‐monomers from aliphatic diacids and diols are introduced, utilizing existing industrial equipment for complete PET utilization. PEXT features a programmable molecular structure, delivering tailored mechanical, thermal, and biodegradation performance. Notably, PEXT exhibits superior mechanical performance, with a maximal elongation at break of 3419.2 % and a toughness of 270.79 MJ m−3. These characteristics make PEXT suitable for numerous applications, including shape‐memory materials, transparent films, and fracture‐resistant stretchable components. Significantly, PEXT allows closed‐loop recycling within specific biodegradable analogs by reprograming PET or X‐monomers. This strategy not only offers cost‐effective advantages in large‐scale upcycling of waste PET into advanced materials but also demonstrates its enormous prospect in environmental conservation. [ABSTRACT FROM AUTHOR]

Several organisms are able to polycondensate tetraoxosilicic(IV) acid to form silicon(IV) dioxide using polycationic molecules. According to an earlier mechanistic proposal, these molecules undergo a phase separation and recent experimental evidence appears to confirm this model. At the same time, polycationic proteins like lysozyme can also promote polycondensation of silicon(IV) dioxide, and they do so under conditions that are not compatible with liquid‐liquid phase separation. In this manuscript we investigate this conundrum by molecular simulations. [ABSTRACT FROM AUTHOR]

Since the seminal work presented by Olah in 1966 on fluorinated carbocations, several strategies have been presented to introduce fluorinated moieties in polymer backbones via carbocation chemistry. The hexafluoroisopropylidene (6F) group is well known for its ability to enhance thermal properties and processability of polymers. However, its direct electrophilic incorporation into polymers has been largely ignored due to the challenges posed by activating hexafluoroacetone monomer for electrophilic aromatic substitution (EAS). In this article, we review the role of fluorinated carbocations from 1966 up to our recent versatile fluoroalkylation strategy to directly enchain the 6F group in polymers. Via EAS interfacial polymerization we reacted hexafluoroacetone trihydrate (HFAH) with aromatic monomers in triflic anhydride (Tf2O) and 1,2-dichloroethane (DCE) with Aliquat® 336. In addition, the polymerization of dibenzo-1,4-dioxin with HFAH is presented. A semi-fluorinated diol, 4,4′-bis(2-hydroxyhexafluoroisopropyl)diphenyl ether, was synthesized by this method and used to prepare the first reported polycarbonate with hexafluoroisopropoxy groups –C(CF3)2O– incorporated in the main chain via polycondensation. Polysilyl ethers were also prepared from this diol. Additionally, we briefly mention Carraher's legacy in the synthesis of metal-containing polymers via reactions of group IVB metallocene dichloride with dinucleophiles (diamines, diol, dicarboxylic acids, and dithiols) in solution and interfacial conditions in terms of electrophilic vs nucleophilic polycondensation. The new acidic, sterically hindered semi-fluorinated diol and bisphenol AF were reacted with group IVB metallocene dichloride in attempts to form metallocene condensation polymers with improved solubility. [ABSTRACT FROM AUTHOR]

This work outlines the synthesis of Schiff base derivatives through the reaction of O-acyl salicylaldehyde with diverse amines, facilitated by ethanol as a solvent. The derivatives were structurally analyzed using 1H and 13C-NMR, FT-IR, and LC–MS techniques. The Schiff base derivative, bearing a phenol moiety, subsequently underwent oxidative polycondensation reaction in water, employing NaOCl as the mild and safe oxidant, presenting a sustainable alternative to conventional methods. The polymer was then subjected to investigations using 1H-NMR, FT-IR, DSC, TGA, SEM, and EDX spectroscopies, revealing exceptional thermal stability suitable for high-temperature applications. The results not only contribute to the development of poly(azomethine-ester) but also highlight the importance of adopting environmentally friendly methodologies in materials synthesis. The findings highlight the potential biological applications of the imine linkage and emphasize the use of green chemistry principles to promote sustainability in synthetic chemistry practices. [ABSTRACT FROM AUTHOR]

Liquid crystal polyesters (LCPs) have attracted growing attention due to the increasing demand for military equipment and 5G communication devices. Commonly, the LCPs are polymerized by transesterification reaction catalyzed through inorganic salts, however, the effects of anionic pairs of catalysts on the LCP polymerization have not been studied carefully. Herein, five kinds of sodium salts with varied anionic pairs as catalysts to facilitate LCP polymerization are investigated for the first time. The catalytic activity is analyzed by the evolution of the liquid crystal (LC) phase during polymerization based on the thin-film polymerization technique. The temperature from 190 °C to 270 °C and the catalyst content in the range from 0 to 0.1 wt% are compared, demonstrating that temperature at 270 °C and catalyst content at 0.1 wt% are the best polymerization conditions for all sodium salts. It is found that sodium formate has the best catalytic activity for the polymerization of LCP in all experimental conditions, in comparison with sodium acetate, sodium propionate, sodium butyrate, and sodium p-hydroxybenzoate. The successful polymerization is also determined by FT-IR spectra, performing the declined intensity of vibration peak at 1370 cm−1 ascribed to the vanishment of acetoxy groups as well as the enhanced intensity of vibration peak at 1735 cm−1 ascribed to the formation of ester groups. [ABSTRACT FROM AUTHOR]

Ring‐opening polymerizations (ROPs) of l‐lactide (LA) were performed with ethyl l‐lactate or 11‐bromoundecanol as initiators (In) and tin(II) ethyl hexanoate (SnOct2) as catalyst (Cat) using four different LA/In ratios (20/1, 40/1, 60/1, and 100/1). One series of ROPs was conducted in bulk at 120 °C, yielding PLAs with low dispersities (Ð ~ 1.2–1.4), and a second series was conducted in bulk at 160 °C, yielding higher dispersities (Ð ~ 1.3–1.9). Samples from both series were annealed for 1 or 14 days at 140 °C in the presence of SnOct2. Both polycondensation and disproportionation reactions occurred, so that all four samples tended to form the same type of molar mass distribution below 10,000 Da, regardless of their initially different number average molar masses (Mn). Both initiators gave nearly identical results. The thermodynamic control of all reversible transesterification processes favored the formation of crystallites composed of chains with a Mn around 3500–3700, corresponding to a crystal thickness of 10–13 nm. [ABSTRACT FROM AUTHOR]

Herein, we report the design and synthesis of a novel chiral heterogeneous catalyst by condensation polymerization of 1,4-phthalaldehyde and amine-containing chiral bis(oxazoline) ligands, followed by partial carbonization and coordination with copper. The catalyst exhibited high activity, superior enantioselectivity (even better than the homogeneous catalyst) and outstanding recyclability in heterogeneous asymmetric Henry reaction. [ABSTRACT FROM AUTHOR]

A green and sustainable --COOH & --OH condensation solution polymerization method was hereby reported for FDCA-based polyesters to avoid discoloration and toxic solvents. First, taking poly(ethylene 2,5-furandicarboxylate) (PEF) as the representative of FDCA-based polyester, enabling good white appearance PEF with Mn=6.51x10³ gmol-1 from FDCA and ethylene glycol in green solvent γ-valerolactone (GVL), catalyzed by 4-dimethylaminopyridine (DMAP) and N-(3-dimethylaminopropyl)-N'-ethylcarbodiimide hydrochloride (EDC). Additionally, the molecular weight of PEF was rapidly improved (Mn >2.5x104 gmol-1) via remelting polycondensation within minutes, with the dispersity still kept relatively low dispersity (Đ<1.40). Importantly, the --COOH & --OH condensation solution polymerization method was successfully applied for the synthesis of various FDCA-based polyesters, including diols with varying carbon chain lengths (3 to 11 carbons) and cycloalkyl diols, especially the applicability of this method to diols containing C=C double bonds, which was found to exhibit low heat resistance. Lastly, assisting with 13C labeled 1,4-succinic acid and in-situ 13C-NMR, an in-depth study of the possible catalytic mechanism was proposed, by which, EDC activated FDCA, and then DMAP catalyzed it with diol to yield macromolecular chain of polyester. Overall, the results provided a green and sustainable strategy for the synthesis of FDCA-based polyesters. [ABSTRACT FROM AUTHOR]