Copolymerization Of Monomers Research Articles

Hofmeister Effect Mediated Conductivity of Hydrogel Electrolytes for High Performance Supercapacitor

AbstractRegulating the performance of hydrogel electrolytes by Hofmeister effect has attracted great interest. However, the Hofmeister effects of cations on the conductivity of hydrogel electrolytes are rarely reported. Here, hydrogel electrolytes (polySA) have been fabricated by random copolymerization of zwitterionic monomers in the presence of NH4Cl, NaCl and LiCl. The weak interaction between NH4+ with water and molecular chains makes polySA‐NH4+ electrolyte have high conductivity at room temperatures, whereas the strong interaction between Li+ with water and molecular chains makes polySA‐Li+ electrolyte possess good anti‐freezing properties and high mechanical strength. The polySA‐Li+ hydrogel electrolyte can have a conductivity of 9.63 mS cm−1 at −35 °C. Supercapacitors assembled with polySA‐Li+ offers high specific capacitance of 52.25 F g−1 at 25 °C and 47.75 F g−1 at −35 °C. The capacitance retention is 94.64 % after 10 days at −35 °C. Our work shows that different properties of hydrogel electrolytes can be achieved by regulating Hofmeister effect, which provides a new way to prepare high‐performance energy storage materials.

POSS and PAG Dual-Containing Chemically Amplified Photoresists by RAFT Polymerization for Enhanced Thermal Performance and Acid Diffusion Inhibition

A random copolymer (PTBM), utilized as deep ultra-violet (DUV) photoresist, was prepared by reversible addition-fragmentation chain transfer (RAFT) polymerization with tert-butyl methacrylate (tBMA), methyl methacrylate (MMA), triphenylsulfonium p-styrenesulfonate (TPS-SS), and functional poly (sesquicarbonylsiloxanes) (POSS-MA) as the monomer components, and 4-cyano-4-[(dodecylsulfanylthiocarbonyl) sulfanyl]pentanoic acid (CDSPA) as the RAFT reagent. Fourier transform infrared spectroscopy (FT-IR) and proton nuclear magnetic resonance (1H NMR) proved successful synthesis. Ultraviolet absorption spectroscopy (UV) analysis verified the transparency of the polymer in the DUV band. RAFT polymerization kinetics showed that the polymerization rate conformed to the first-order kinetic relationship, and the polymerization process exhibited a typical controlled free radical polymerization behavior. Thermogravimetric analysis (TGA), differential scanning calorimetry (DSC) and static thermo-mechanical analysis (TMA) showed that the incorporation of POSS groups improved the thermal properties of the copolymer. According to scanning electron microscopy (SEM) images, the copolymerization of photoacid monomers (TPS-SS) resulted in photoresist copolymers exhibiting good resistance to acid diffusion and low roughness.

Low swelling and high mechanical strength organosilane hybrid polydivinylbenzene microspheres for hydrophilic interaction chromatography applications.

In this work, monodisperse organosilane hybrid polymer microspheres with a particle size of about 5µm were synthesized using seed swelling polymerization. The organosilicon reagent methacryloxypropyltrimethoxysilane was introduced into the polymer framework as a copolymerization monomer, and the crosslinking degree of the microspheres was improved by the hydrolysis-condensation reaction of siloxanes. The synthesized hybrid microspheres have good mechanical strength as well as low swelling, with swelling propensity values of 0.167 and 0.348 in methanol and acetonitrile, respectively. Hybrid microspheres modified with cysteine have a hydrophilic interaction chromatography/reversed-phase liquid chromatography mixed-mode retention mechanism. Compared to the commercial cysteine-modified silica column, the synthesized stationary phase has higher separation selectivity for partially acidic or basic samples and better basic resistance for use under high pH mobile phase conditions (at least 10).

Effect of anionic groups in zwitterionic hydrophilic stationary phases on their chromatographic characteristics

The structure of zwitterion has great impact on the separation properties of zwitterionic hydrophilic stationary phases. To better understand the role of anionic groups of zwitterions, a novel carboxybetaine-based zwitterionic monolithic column was first prepared through thermo-initiated copolymerization of functional monomer (3-acrylamidopropyl)-dimethyl-(2-carboxymethyl) ammonium (CBAA) and crosslinker ethylene dimethacrylate (EDMA) within 100 μm ID capillary. The optimal poly(CBAA-co-EDMA) monolithic column exhibited satisfactory mechanical and chemical stability, good repeatability, high column efficiency (96,000 plates/m), and excellent separation performance for different classes of polar compounds (i.e., phenols, monophosphate nucleotides, urea and allantoin). A comparative study was then performed among three zwitterionic hydrophilic stationary phases containing different anionic groups, i.e. poly(CBAA-co-EDMA) (carboxybetaine), poly(2-{2-(methacryloyloxy) ethyldimethylammonium}ethyl n-butyl phosphate-co-EDMA) (phosphocholine), and poly(N,N-dimethyl-N-(3-methacrylamidopropyl)-N-(3-sulfopropyl) ammonium betaine-co-EDMA) (sulfobetaine) using benzoic acid derivatives, amine compounds, nucleobases and nucleosides as model analytes. The carboxybetaine-based monolithic column exhibited much higher positive zeta-potential and hydrophilicity, which endows it with a stronger retention capacity for acidic and neutral compounds, but sulfobetaine-based monolithic column exhibited much higher selectivity and retention capacity for the amines. Moreover, their enrichment efficiencies for N-glycopeptides were also evaluated based on their different hydrophilicity, and it was observed that the poly(CBAA-co-EDMA) monolithic material captured 4-8 times more N-glycopeptides compared to the other two materials.

Synthesis and properties of AM/AMPS/MMA and cationic monomer copolymer flooding agent

Abstract A novel hydrophobic association copolymer (PAMA) was synthesized by incorporating acrylamide (AM), 2-acrylamide-2-methylpropanesulfonic acid (AMPS), cationic monomer (MEDDA), and methyl methacrylate (MMA). The properties of MMA copolymers with varying contents were analyzed using infrared spectroscopy, nuclear magnetic resonance spectroscopy, and scanning electron microscopy. Optimal overall performance of the solution was achieved when the MMA content reached 1.4 % w/w. Compared to pure PAAM (without MMA), the PAMA-1.4 % polymer exhibited superior viscoelasticity, temperature resistance, and shear resistance. This enhancement in PAMA performance can be attributed to the significant inhibition of intermolecular water film formation within the polymer matrix by MMA, effectively improving and regulating solution solubility while strengthening molecular chain interactions and enhancing the structural network strength of PAMA polymers. Additionally, the inclusion of MMA transformed rock surfaces from non-wetting to wetting conditions, thereby greatly improving oil displacement efficiency. In displacement experiments, PAMA-1.4 % performed better in terms of enhanced oil recovery, the recovery rate of 0.1 % w/w PAMA-2.4 % solution is only 7.78 %, while the recovery rate of 0.1 % w/w PAMA-1.4 % solution is 13.06 %.

Enhancing Suppression of Chain Transfer via Installing Bulky N‐ortho‐Aryl Substituents into α‐Diimine Nickel System

AbstractRecently, the important role of sterically bulky aromatic substituents at the axial position of the metal center for synthesizing high‐performance catalysts were recognized. In this study, a series of α‐diimine nickel complexes with bulky N‐ortho‐aryl substituents were designed and synthesized. The as‐synthesized nickel complexes showed high activities (up to 2.3×107 g ⋅ mol−1 ⋅ h−1) and superior thermostability, giving access to moderately branched polyethylenes (35–86/1000 C) with high molecular weights (up to 197.5×104 g ⋅ mol−1). The polyethylene materials generated by these nickel complexes at 80 °C exhibited outstanding tensile mechanical. In addition, these nickel complexes could also catalyze the copolymerization of ethylene and polar monomer with modest activity (such as undecenoic acid, 10‐undecen‐1‐ol and 6‐chlorohex‐1‐ene), yielding functionalized polyolefin with adjustable molecular weights (6.8–222.9×104 g ⋅ mol−1) and incorporation ratios (0.2–4.3 mol %).

The effect of chain transfer reactions on the relative activity of monomers in radical copolymerization

A scientific hypothesis on the effect of chain transfer reactions on the relative activity of monomers in radical copolymerization is theoretically substantiated. It is concluded that when binary copolymerization of monomers is carried out in the presence of active chain carriers, the compositional homogeneity of the obtained copolymers will deteriorate.

Temperature-Tolerant Versatile Conductive Zwitterionic Nanocomposite Organohydrogel toward Multisensory Applications.

Conductive hydrogels (CHs) are emerging materials for next generation sensing systems in flexible electronics. However, the fabrication of competent CHs with excellent stretchability, adhesion, self-healing, photothermal conversion, multisensing, and environmental stability remains a huge challenge. Herein, a nanocomposite organohydrogel with the above features is constructed by in situ copolymerization of zwitterionic monomer and acrylamide in the existence of carboxylic cellulose nanofiber-carrying reduced graphene oxide (rGO) plus a solvent displacement strategy. The synergy of abundant dipole-dipole interactions and intermolecular hydrogen bonds enables the organohydrogel to exhibit high stretchability, strong adhesion, and good self-healing. The presence of glycerol weakens the formation of hydrogen bonds between water molecules, endowing the organohydrogel with excellent environmental stability (-40 to 60 °C) to adapt to different application scenarios. Importantly, the multimodal organohydrogel presents excellent sensing behavior, including a high gauge factor of 16.3 at strains of 400-1440% and a reliable thermal coefficient of resistance (-4.2 °C-1) over a wide temperature widow (-40 to 60 °C). Moreover, the organohydrogel displays a highly efficient and reliable photothermal conversion ability due to the favorable optical absorbing behavior of rGO. Notably, the organohydrogel can detect accurate human activities at ambient temperature, demonstrating potential applications in flexible intelligent electronics.

Synthesis of Photoresponsive Fast Self-healing Polyolefin Composites by Nickel-Catalyzed Copolymerization of Ethylene and Lignin Cluster Monomers.

Polymers may suffer from sudden mechanical damages during long-term use under various harsh operating environments. Rapid and real-time self-healing will extend their service life, which is particularly attractive in the context of circular economy. In this work, a lignin cluster polymerization strategy (LCPS) was designed to prepare a series of lignin functionalized polyolefin composites with excellent mechanical properties through nickel catalyzed copolymerization of ethylene and lignin cluster monomers. These composites can achieve rapid self-healing within 30 seconds under a variety of extreme usage environments (underwater, seawater, extremely low temperatures as low as -60 °C, organic solvents, acid/alkali solvents, etc.), which is of great significance for real-time self-healing of sudden mechanical damage. More importantly, the dynamic cross-linking network within these composites enable great re-processability and amazing sealing performances.

Synthesis of Photoresponsive Fast Self‐healing Polyolefin Composites by Nickel‐Catalyzed Copolymerization of Ethylene and Lignin Cluster Monomers

AbstractPolymers may suffer from sudden mechanical damages during long‐term use under various harsh operating environments. Rapid and real‐time self‐healing will extend their service life, which is particularly attractive in the context of circular economy. In this work, a lignin cluster polymerization strategy (LCPS) was designed to prepare a series of lignin functionalized polyolefin composites with excellent mechanical properties through nickel catalyzed copolymerization of ethylene and lignin cluster monomers. These composites can achieve rapid self‐healing within 30 seconds under a variety of extreme usage environments (underwater, seawater, extremely low temperatures as low as −60 °C, organic solvents, acid/alkali solvents, etc.), which is of great significance for real‐time self‐healing of sudden mechanical damage. More importantly, the dynamic cross‐linking network within these composites enable great re‐processability and amazing sealing performances.

Polymer dispersity modulation by statistical copolymerization of (α-alkyl)acrylate monomers with disparate reactivity: Enhanced monomer conversion and tailored dispersity for dielectric elastomer application

Polymer dispersity (Ð) is an important parameter in determining polymer properties. We report a new strategy for Ð modulation by statistically copolymerizing steric-hindered itaconates with methacrylate and acrylate monomers via organocatalyzed controlled radical polymerization. Due to the disparate monomer reactivity, Ð values can be tunable in a broad range (1.1–1.6) in a batch system. This strategy has demonstrated the sequential and topological generality for Ɖ modulations, serving as a model tool for Ð modulation in any segment of A-B diblock, B-A-B and A-B-A triblock, and 3-arm star A-B diblock copolymers. The unique aspects of this method are that the segment after Ð modulation can initiate polymerization of various types of monomers (e.g., methacrylate, acrylate) by the labile tertiary carbon-iodide chain-end without any external assistance or special initiator and monomer selection, the metal-free nature and the renewable substitution of petroleum-based methacrylate and acrylate monomers with bio-based itaconates without sacrificing inherent properties. This work broadens the application scope of Ð modulation to many other emerging technologies, such as antifreezing thermoplastic dielectric elastomers used as film capacitors in the field of energy storage.

Adhesive and healable supramolecular comb-polymers

A series of supramolecular comb polymers (SCPs) with adhesive and healable characteristics have been generated through the copolymerisation of methacrylate monomers featuring aromatic amide functionalities with lauryl methacrylate. By varying the amide functionality and loading of the supramolecular monomers, the properties of the resulting SCPs can be tailored, ultimately providing stable films at room temperature. As the loading of the amide-bearing monomer was increased, the phase separation between the hard and soft domains was enhanced, promoting larger hard-domain aggregation, as observed via atomic force microscopy (AFM). The mechanical properties of the SCPs correlated to the loading of the amide-bearing monomers, by increasing the mol% incorporation the resulting SCPs transition from possessing high strain to high ultimate tensile strength (UTS) and Young's modulus (YM). Over several re-adhesion cycles, the SCPs were shown to retain their shear strength when thermally adhered to both glass and aluminium substrates. Additionally, the SCPs exhibited healable properties at elevated temperatures (> 45 °C) allowing for the recovery of mechanical properties post-damage.

Covalently Merging Ionic Liquids and Conjugated Polymers: A Molecular Design Strategy for Green Solvent‐Processable Mixed Ion–Electron Conductors Toward High‐Performing Chemical Sensors

AbstractPolymeric mixed ionic–electronic conductors hold great potential for advancing high‐performance organic electronics due to their exceptional electrical conductivity achieved through ion–electron coupling. However, the widespread adoption of these conductors faces obstacles due to their reliance on environmentally harmful solvents during processing and the potential performance degradation under various conditions. In this study, a practical solution to these challenges is proposed by incorporating monomers with ionic liquid‐behaving pendant groups into conjugated polymers. The copolymerization of these charged monomers not only improves solubility in environmentally friendly solvents but also imparts long‐term stability against humidity, high temperatures, and mechanical deformation. The immobilized ion species foster highly selective interactions of these polymers with nitrogen dioxide, paving the way for the development of stretchable sensing devices capable of functioning at exceptionally high temperatures.

Recent Advances in Nickel Catalysts with Industrial Exploitability for Copolymerization of Ethylene with Polar Monomers.

The direct copolymerization of ethylene with polar monomers to produce functional polyolefins continues to be highly appealing due to its simple operation process and controllable product microstructure. Low-cost nickel catalysts have been extensively utilized in academia for the synthesis of polar polyethylenes. However, the development of high-temperature copolymerization catalysts suitable for industrial production conditions remains a significant challenge. Classified by the resultant copolymers, this review provides a comprehensive summary of the research progress in nickel complex catalyzed ethylene-polar monomer copolymerization at elevated temperatures in the past five years. The polymerization results of ethylene-methyl acrylate copolymers, ethylene-tert-butyl acrylate copolymers, ethylene-other fundamental polar monomer copolymers, and ethylene-special polar monomer copolymers are thoroughly summarized. The involved nickel catalysts include the phosphine-phenolate type, bisphosphine-monoxide type, phosphine-carbonyl type, phosphine-benzenamine type, and the phosphine-enolate type. The effective modulation of catalytic activity, molecular weight, molecular weight distribution, melting point, and polar monomer incorporation ratio by these catalysts is concluded and discussed. It reveals that the optimization of the catalyst system is mainly achieved through the methods of catalyst structure rational design, extra additive introduction, and single-site catalyst heterogenization. As a result, some outstanding catalysts are capable of producing polar polyethylenes that closely resemble commercial products. To achieve industrialization, it is essential to further emphasize the fundamental science of high-temperature copolymerization systems and the application performance of resultant polar polyethylenes.

Low-Migration Compounds with Amine Functionality as Coinitiators of Radical Polymerization.

The utilization of two-component systems comprising camphorquinone (CQ) and aromatic amines has become prevalent in the photopolymerization. However, there are still concerns about the safety of this CQ/amine system, mainly because of the toxicity associated with the leaching of aromatic amines. In light of these concerns, this study aims to develop novel coinitiator combinations featuring CQ and amines which cannot be leached out of materials, enabling free radical polymerization of representative dentalmethacrylate resins under blue light irradiation. This approach involves the initial design and analysis of hydrogen donors with low C─H bond dissociation energy through molecular modeling. Subsequently, copolymerizable methacrylate functional groups are incorporated via chemical modification, allowing it to act as both coinitiator and copolymerization monomer to achieve low migrationand leachability properties. This work presents, for the first time, the synthesis of the innovative coinitiator and compares its performance with the benchmark CQ/ethyl-4-dimethylaminobenzoate (EDB)-based photoinitiation system (PIS). The results demonstrate the effectiveness of the newly proposed PIS. Finally, an in-depth investigation is conducted into the reaction mechanism associated with this PIS through molecular orbital calculations and electron spin resonance studies.

Enhancing Wastewater Depollution: Sustainable Biosorption Using Chemically Modified Chitosan Derivatives for Efficient Removal of Heavy Metals and Dyes.

Driven by concerns over polluted industrial wastewater, particularly heavy metals and dyes, this study explores biosorption using chemically cross-link chitosan derivatives as a sustainable and cost-effective depollution method. Chitosan cross-linking employs either water-soluble polymers and agents like glutaraldehyde or copolymerization of hydrophilic monomers with a cross-linker. Chemical cross-linking of polymers has emerged as a promising approach to enhance the wet-strength properties of materials. The chitosan thus extracted, as powder or gel, was used to adsorb heavy metals (lead (Pb2+) and copper (Cu2+)) and dyes (methylene blue (MB) and crystal violet (CV)). Extensive analysis of the physicochemical properties of both the powder and hydrogel adsorbents was conducted using a range of analytical techniques, including Fourier transform infrared spectroscopy (FTIR), X-ray diffraction (XRD), Brunauer-Emmett-Teller (BET), and scanning electron microscopy (SEM), as well as 1H and 13C nuclear magnetic resonance (NMR). To gain a comprehensive understanding of the sorption process, the effect of contact time, pH, concentration, and temperature was investigated. The adsorption capacity of chitosan powder for Cu(II), Pb(II), methylene blue (MB), and crystal violet (CV) was subsequently determined as follows: 99, 75, 98, and 80%, respectively. In addition, the adsorption capacity of chitosan hydrogel for Cu(II), Pb(II), MB, and CV was as follows: 85, 95, 85, and 98%, respectively. The experimental data obtained were analyzed using the Langmuir, Freundlich, and Dubinin-Radushkevich isotherm models. The isotherm study revealed that the adsorption equilibrium is well fitted to the Freundlich isotherm (R2 = 0.998), and the sorption capacity of both chitosan powder and hydrogel was found to be exceptionally high (approximately 98%) with the adsorbent favoring multilayer adsorption. Besides, Dubinin has given an indication that the sorption process was dominated by Van der Waals physical forces at all studied temperatures.

Hydrophilic Poly(meth)acrylates by Controlled Radical Branching Polymerization: Hyperbranching and Fragmentation.

Topology significantly impacts polymer properties and applications. Hyperbranched polymers (HBPs) synthesized via atom transfer radical polymerization (ATRP) using inimers typically exhibit broad molecular weight distributions and limited control over branching. Alternatively, copolymerization of inibramers (IB), such as α-chloro/bromo acrylates with vinyl monomers, yields HBPs with precise and uniform branching. Herein, we described the synthesis of hydrophilic HB polyacrylates in water by copolymerizing a water-soluble IB, oligo(ethylene oxide) methyl ether 2-bromoacrylate (OEOBA), with various hydrophilic acrylate comonomers. Visible-light-mediated controlled radical branching polymerization (CRBP) with dual catalysis using eosin Y (EY) and copper complexes resulted in HBPs with various molecular weights (M n = 38 000 to 170 000) and degrees of branching (2%-24%). Furthermore, the optimized conditions enabled the successful application of the OEOBA to synthesize linear-hyperbranched block copolymers and hyperbranched polymer protein hybrids (HB-PPH), demonstrating its potential to advance the synthesis of complex macromolecular architecture under environmentally benign conditions. Copolymerization of hydrophilic methacrylate monomer, oligo(ethylene oxide) methyl ether methacrylate (OEOMA500), and inibramer OEOBA was accompanied by fragmentation via β-carbon C-C bond scission and subsequent growth of polymer chains from the fragments. Furthermore, computational studies investigating the fragmentation depending on the IB and comonomer structure supported the experimental observations. This work expands the toolkit of water-soluble inibramers for CRBP and highlights the critical influence of the inibramer structure on reaction outcomes.

Effect of Gold Nanoparticle Size on Regulated Catalytic Activity of Temperature-Responsive Polymer-Gold Nanoparticle Hybrid Microgels.

Gold nanoparticles (AuNPs) possess attractive electronic, optical, and catalytic properties, enabling many potential applications. Poly(N-isopropyl acrylamide) (PNIPAAm) is a temperature-responsive polymer that changes its hydrophilicity upon a slight temperature change, and combining PNIPAAm with AuNPs allows us to modulate the properties of AuNPs by temperature. In a previous study, we proposed a simpler method for designing PNIPAAm-AuNP hybrid microgels, which used an AuNP monomer with polymerizable groups. The size of AuNPs is the most important factor influencing their catalytic performance, and numerous studies have emphasized the importance of controlling the size of AuNPs by adjusting their stabilizer concentration. This paper focuses on the effect of AuNP size on the catalytic activity of PNIPAAm-AuNP hybrid microgels prepared via the copolymerization of N-isopropyl acrylamide and AuNP monomers with different AuNP sizes. To quantitatively evaluate the catalytic activity of the hybrid microgels, we monitored the reduction of 4-nitrophenol to 4-aminophenol using the hybrid microgels with various AuNP sizes. While the hybrid microgels with an AuNP size of 13.0 nm exhibited the highest reaction rate and the apparent reaction rate constant (kapp) of 24.2 × 10-3 s-1, those of 35.9 nm exhibited a small kapp of 1.3 × 10-3 s-1. Thus, the catalytic activity of the PNIPAAm-AuNP hybrid microgel was strongly influenced by the AuNP size. The hybrid microgels with various AuNP sizes enabled the reversibly temperature-responsive on-off regulation of the reduction reaction.

Прививочная полимеризация акриловых мономеров на полиэтиленовую поверхность (обзор)

A search and review of English-language scientific literature about the graft copolymerization of acrylic monomers onto a solid-phase polymeric surface has been carried out. Grafting onto plates and films of high- and low-density polyethylene is considered. The monomers used were acrylic and methacrylic acids, glycidyl acrylate and glycidyl methacrylate, etc., and the main method was UV photopolymerization with an initiator – benzophenone, etc. Problems of graft polymerization in terms of surface modification of polymeric materials are touched upon, and possible areas of their application are outlined.

Synthesis of ultra-high molecular weight homo- and copolymers via an ultrasonic emulsion process with a fast rate

In the forefront of advanced materials, ultra-high molecular weight (UHMW) polymers, renowned for their outstanding mechanical properties, have found extensive applications across various domains. However, their production has encountered a significant challenge: the attainment of UHMW polymers with a low dispersity (Ɖ). Herein, we introduce the pioneering technique of ultrasound (US) initiated polymerization, which has garnered attention for its capability to successfully polymerize a multitude of monomers. This study showcases the synthesis of UHMW polymers with a comparatively low Ɖ ( ≤ 1.1) within a remarkably short duration ( ~ 15 min) through the amalgamation of emulsion polymerization and high-frequency ultrasound-initiated polymerization. Particularly noteworthy is the successful copolymerization of diverse monomers, surpassing the molecular weight and further narrowing the Ɖ compared to their respective homopolymers. Notably, this includes monomers like vinyl acetate, traditionally deemed unsuitable for controlled polymerization. The consistent production and uniform dispersion of radicals during ultrasonication have been identified as key factors facilitating the swift fabrication of UHMW polymers with exceptionally low Ɖ.