Explore the vast range of titles available.

Aliphatic polyesters and polycarbonates are among the promising sustainable polymers, which exhibit unique degradability and chain‐chain interactions owing to their heterofunctionality. However, monocomponent aliphatic polyesters and polycarbonates usually suffer from inferior properties and functionalities. By contrast, precisely modulated block copolymers composed of polyesters and polycarbonates give rise to sustainable materials with tailored performance. An efficient approach to synthesize the block copolymers is the ring‐opening (co)polymerization of the heterocycle monomers. Herein, this review presents the heterocycle monomer ring‐opening (co)polymerization for the formation of sequence‐controlled block polyesters and polycarbonates. Available synthetic strategies, different monomers, monomer combinations and the catalyst systems for the formation of different block polyesters and polycarbonates are summarized. Block copolymers are fundamental for the development of smart molecules. Aliphatic polyesters and polycarbonates have received attention as heteroatom‐containing polymers that are biodegradable and biocompatible. Block polymers from polyesters and polycarbonates have the ability to form smart molecules. This review presents the heterocycle monomer ring‐opening (co)polymerization for the synthesis of sequence‐controlled block polyesters and polycarbonates.

The ability of poly-ferric-silicate-sulphate (PFSS) synthesized via a co-polymerization process has been applied for the removal of diazo Congo red dye. A novel degradation pathway of diazo Congo red dye by using PFSS is proposed based on LC–MS analysis. Diazo Congo red dye was successfully removed using synthesized PFSS at lower coagulant dosages and a wider pH range, i.e., 9 mg/L from pH 5 to 7, 11 mg/L at pH 9, and 50 mg/L at pH 11. The azo bond cleavage was verified by the UV–Vis spectra of diazo Congo red-loaded PFSS and FTIR spectra which showed disappearance of the peak at 1584 cm−1 for –N=N– stretching vibrations. The synchronized results of UV–Vis spectra, FTIR, and the LC–MS analysis in this study confirmed the significance of the Si and Fe bond in PFSS towards the degradation of diazo Congo red dye. The successfully synthesized PFSS coagulant was characterized by FTIR, SEM, TEM, and HRTEM analysis. From this analysis, it was proven that PFSS is a polycrystalline material which is favorable for the coagulation–flocculation process. Based on all these findings, it was established that synthesized PFSS can be employed as a highly efficient polymeric coagulant for the removal of dye from wastewater.

Biodegradable polymers are a promising sustainable alternative to conventional petroleum-based polymers and have attracted recent extensive research interest due to their potential environmental friendliness and sustainability. Among them, aliphatic polyesters and polycarbonates are the most extensively studied ones. The metal-catalyzed ring-opening polymerization (ROP) of cyclic esters and ring-opening copolymerization (ROCOP) of epoxides with anhydrides or CO 2 are often considered to be the classic and efficient methods to synthesize stereoregular polymers. Moreover, the versatile salen-type metal complexes have been used to prepare almost all types of biodegradable polymers with excellent stereoselectivity control. Hence, this review focuses on stereoselective synthesis of biodegradable polymers by salen-type metal catalysts developed in the last decade. Aliphatic polyesters from ROP of cyclic esters, ROCOP of epoxides with cyclic anhydrides, and carbonylative polymerization of epoxides, as well as aliphatic poly(thio)carbonate from ROCOP of epoxides with CO 2 or COS are discussed in detail. This review highlights the polymerization mechanisms, catalyst characteristics, and factors controlling the stereoselectivity of each polymerization reaction, aiming to provide general rules for the future design of stereoselective catalysts.

Transparent polyimides with excellent mechanical properties and high optical transmittance have been widely used in various optical and electrical applications. However, due to the rigidity of their aromatic structure, their flexibility is limited, making them unsuitable for applications requiring different form factors, such as flexible display cover windows. Furthermore, the refractive index of most transparent polyimides is approximately 1.57, which differs from that of the optically clear adhesives (OCAs) and window materials that have values typically around 1.5, resulting in visual distortion. This study employed 4,4′-(hexafluoroisopropylidene)diphthalic anhydride (6FDA) and 2,2′-bis(trifluoromethyl)benzidine (TFMB) as the base structure of polyimides (6T). Additionally, 1,3-bis(aminomethyl)cyclohexane (BAC) with a monocyclic structure and bis(aminomethyl)bicyclo[2,2,1]heptane (BBH) with a bicyclic structure were introduced as co-monomers or crosslinking agents to 6T. The mechanical, thermal, and optical properties of the obtained copolymers (6T-BAC and 6T-BBH series) and crosslinked polymers (6T-CL-BAC and 6T-CL-BBH series) were compared. Both the copolymer series (6T-BAC and 6T-BBH) and the crosslinked series (6T-CL-BAC and 6T-CL-BBH) exhibited improved optical properties compared to the conventional 6T, with maximum transmittance exceeding 90% and refractive indices ranging from approximately 1.53 to 1.55. Notably, the copolymer series achieved transmittance levels above 95% and exhibited lower refractive indices (~1.53), demonstrating superior optical performance relative not only to the 6T baseline but also to the crosslinked series. The alicyclic polyimides synthesized in this study exhibited mechanical flexibility, high optical transmittance, and a refractive index approaching 1.5, demonstrating their applicability for use as flexible display cover window materials.

A straightforward and one-step modification of the pencil graphite electrode was performed using co-polymerization of diphenyl amine-4-sulfonic acid (DPASA) sodium salt, and 4-vinylpyridine (VP), and also simultaneous formation of ruthenium dioxide nanoparticles (poly(DPASA-co-VP)-RuO2 NPs/PGE). The subsequent step involved the application of the altered electrode to examine the quantity of sumatriptan by employing a highly sensitive adsorptive differential pulse voltammetric method. The modified electrode was thoroughly characterized through the utilization of cyclic voltammetry (CV), field-emission scanning electron microscopy (FESEM), and electrochemical impedance spectroscopy (EIS). Under optimized conditions, the concentration of sumatriptan was determined within two linear ranges: 1.0–50.0 nM and 50.0–5000.0 nM, with a detection limit of 0.03 nM. Ultimately, the suggested approach was employed to gauge the sumatriptan content in tablet and urine samples, revealing that this method possesses the requisite levels of accuracy and precision.

A highly efficient low-cost adsorbent was prepared using raw and chemically modified cellulose isolated from sugarcane bagasse for decontamination of Cr(VI) from wastewater. First, cellulose pulp was isolated from sugarcane bagasse by subjecting it to acid hydrolysis, alkaline hydrolysis and bleaching with sodium chlorate (NaClO3). Then, the bleached cellulose pulp was chemically modified with acrylonitrile monomer in the presence Fenton’s reagent (Fe+2/H2O2) to carry out grafting of acrylonitrile onto cellulose by atom transfer radical polymerization. The developed adsorbent (acrylonitrile grafted cellulose) was analyzed by X-ray diffraction analysis (XRD), scanning electron microscopy (SEM) and Fourier transform infrared spectroscopy (FT-IR). Both raw cellulose and acrylonitrile grafted cellulose were used for chromium removal from wastewater. The effects of metal ion concentration, pH, adsorbent dose and time were studied, and their values were optimized. The optimum conditions for the adsorption of Cr(VI) onto raw and chemically modified cellulose were: metal ion concentration: 50 ppm, adsorbent dose: 1 g, pH: 6, and time: 60 min. The maximum efficiencies of 73% and 94% and adsorption capacities of 125.95 mg/g and 267.93 mg/g were achieved for raw and acrylonitrile grafted cellulose, respectively. High removal efficiency was achieved, owing to high surface area of 79.92 m2/g and functional active binding cites on grafted cellulose. Isotherm and kinetics studies show that the experimental data were fully fitted by the Freundlich isotherm model and pseudo first-order model. The adsorbent (acrylonitrile grafted cellulose) was regenerated using three different types of regenerating reagents and reused thirty times, and there was negligible decrease (19%) in removal efficiency after using it for 30 times. Hence, it is anticipated that acrylonitrile could be utilized as potential candidate material for commercial scale Cr(VI) removal from wastewater.

Suppressing the chain transfer reactions during polymerization in late-transition metal-catalyzed olefin polymerization systems is the key to obtaining high molecular weight polyolefin materials. In this work, two efficient strategies (“sandwich” and rotation-restricted strategies) to retard chain transfer reactions in ethylene (co)polymerization were employed for the iminopyridyl system. Herein, a family of iminopyridyl Ni(II) and Pd(II) complexes with a flexible backbone and rigid axial bulky aryl substituents were designed, synthesized and characterized. In ethylene polymerization, the iminopyridyl Ni(II) and Pd(II) catalysts using the two strategies exhibited reasonable activities and generated highly branched polyethylenes with high molecular weights, where catalysts with dibenzosuberyl substituents exhibited significantly higher activities and produced higher molecular weight polyethylene than catalysts with 8-arylnaphthalenyl substituent. A similar trend of activities and molecular weights was also found in the copolymerization of ethylene with MA using the Pd(II) catalysts. Moreover, highly branched E-MA copolymers with moderate to high molecular weights and high incorporation ratios (up to 17.4 mol%) were generated with the two Pd(II) catalysts. Most interestingly, as compared with the dibenzhydryl Ni(II) and Pd(II) catalysts, the catalysts using the two strategies exhibited a superior ability to retard the chain transfer reactions and generated polymers and copolymers with 1–2 orders of magnitude higher molecular weights during ethylene (co)polymerization.

Developing an efficient freshwater and electricity co‐generation device (FECGD) can solve the shortage of freshwater and electricity. However, the poor salt resistance and refrigeration properties of the materials for FECGD put big challenges in the efficient and stable operation of these devices. To address these issues, we propose the covalent organic framework (COF) confined co‐polymerization strategy to prepare COF‐modified acrylamide cationic hydrogels (ACH‐COF), where hydrogen bonding interlocking between negatively charged polymer chains and COF pores can form a salt resistant hydrogel for stabilizing tunable passive interfacial cooling (TPIC). The FECPDs based on the TPIC and salt resistance of ACH‐COF display a maximum output power density of 2.28 W m−2, which is 4.3 times higher than that of a commercial thermoelectric generator under one solar radiation. The production rate of freshwater can reach 2.74 kg m−2 h−1. Our results suggest that the high efficiency and scalability of the FECGD can hold the promise of alleviating freshwater and power shortages. Covalent organic framework (COF)‐modified acrylamide cationic hydrogel (ACH‐COF) evaporators has been developed using a COF confined co‐polymerization strategy, which combines the Donnan effect and the Marangoni effect to achieve high salt tolerance and fast evaporative cooling. ACH‐COF has many advantages, such as good mechanical properties, high salt resistance, pollution resistance, environmental sensing, fast passive interfacial cooling, etc., which can be used for seawater desalination and heat dissipation for electronic products. The freshwater and electricity co‐generation units developed based on the combination of the good cooling effect of optimized ACH‐COF and thermoelectric generator have excellent desalination and electricity generation capabilities.

In this study, a chitosan-based high polymer antibacterial agent CS-g-DMC with high water solubility was synthesized via an environmentally friendly initiator system of H2O2 and ascorbic acid (Vc). The CS-g-DMC is used for the long-effective antibacterial finishing of cotton fabric. SEM, EDS, FTIR, XPS, and XRD were conducted to characterize the finished fabric. After the treatment, the CS-g-DMC were cross-linked with cellulose by 1,2,3,4-Butane tetracarboxylic acid BTCA thus immobilized on cotton fabrics. Results showed CS-g-DMC had linked with cellulose by stable chemical bond and uniformly distributed on the surface of cotton fiber. The antibacterial test shows that after treatment, the inhibition rates of the cotton fabric against E. coli and S. aureus are above 99.9%. Moreover, the inhibition rates of the two bacteria reach 94.3% and 95.3% after washing ten times, respectively. The finished cotton fabric had significantly improved hydrophily; its contact angle decreased from 107° to 104°. Its breaking force significantly increased from 173.38 to 219.33 N, while its breaking elongation and moisture transmission rate had no significant decrease. In general, CS-g-DMC-finished cotton fabrics achieve long-lasting antibacterial properties and higher mechanical properties while retaining a high degree of wearing comfort.

High performance thermal insulation materials are urgently demanded for energy saving and thermal protection applications. Organic aerogels are considered as promising and highly efficient thermal insulation materials, but high shrinkage has been a major obstacle to limit their development and application. Herein, by a co-polymerization of formaldehyde (F) and benzoxazine prepolymers, polybenzoxazine with increased crosslink density and thus enhanced gel strength was formed, leading to low shrinkage polybenzoxazine (PBOF) aerogels with hierarchical micro/nanostructures. The hierarchical porous nanoskeleton of PBOF aerogels, composed of stacked thick-united spherical nanoparticles, was formed due to the different solubility of the reactants in N,N -dimethylformamide and F aqueous solution. Benefitting from the low shrinkage (13.22%, exceeding 60% reduction), the PBOF aerogels exhibit a low thermal conductivity of 0.0397 W m −1 K −1 at room temperature and outstanding thermal protection ability at high temperature. A 13 mm thick sample could resist a butane flame of 1300°C for 90 s, and the hand was not burn when touching the back. This strategy enables PBOF aerogels with a new perspective for their applications in civil and military fields.