Copolymer Materials Research Articles

Visible-light-driven Fe-catalyzed alkylation for synthesizing functionalized polyolefin elastomers as advanced encapsulants in photovoltaic modules

Polyolefin elastomer (POE) has emerged as a promising encapsulant for photovoltaic modules, attributed to its exceptional water vapor barrier properties, robust weather resistance, and enhanced anti-potential induced degradation (anti-PID) capabilities. Despite these advantages, the interfacial adhesion of POE remains a significant challenge, particularly its suboptimal bonding with glass and solar cells, which impedes its broader application within the photovoltaic industry. This study introduced glycidyl methacrylate (GMA) monomers into POE through a photo-induced iron-catalyzed alkylation reaction, developing a novel polyolefin encapsulant for photovoltaic modules. The encapsulant was designed to possess high light transmittance, enhanced adhesion, and elevated resistivity. The modified POE boasts an impressive light transmittance nearing 98% and an adhesive strength of 28.3 N cm−1, both superior to traditional ethylene-vinyl acetate copolymer (EVA) materials. Additionally, this work delves into the correlation between crystallization behavior and light transmittance, elucidating the influence of GMA incorporation on the adhesion and insulation properties of POE through gaussian simulations.

Thin film nanocomposite membranes based on renewable polymer Pebax® and zeolitic imidazolate frameworks for CO2/CH4 separation

This study investigates the impact of integrating Pebax® Rnew® 30R51, a sustainable elastomer-type copolymer material, with zeolitic imidazolate frameworks (ZIFs) to develop advanced membranes for CO2/CH4 gas separation. The fabrication process of ZIF/Pebax® Rnew® 30R51 thin films was optimized to achieve uniform and defect-free thin film composite (TFC) membranes. Crucial membrane properties, including permeability, selectivity and separation efficiency, were analyzed with variations in ZIF type, loading levels, film thickness and operating conditions. Additionally, the resulting TFC and ZIF/Pebax® Rnew® 30R51 thin film nanocomposite (TFN) membranes were subjected to characterization via FTIR, XRD, TGA and SEM to evaluate their physicochemical properties. Nanoparticles of ZIF-8, NH2-ZIF-8 and ZIF-94 were individually added (at 5–15 wt% loadings) to the Pebax® Rnew® 30R51 matrix to develop the CO2 separation efficiency. The pristine TFC membrane showed a 66 GPU CO2 permeance and a 37.5 CO2/CH4 separation selectivity, primarily due to improved CO2 mass transport. Upon inclusion of ZIFs, the CO2 permeance with 5 wt% loadings of ZIF-8, NH2-ZIF-8 and ZIF-94 increased to 148, 99 and 125 GPU, respectively, despite this, the CO2/CH4 separation selectivity maintained at 29.4, 37.0 and 27.0, respectively.

Manufacture of Solid Propellants Based on Renewable Succinic Acid Polyols

AbstractModern energy policies encourage the replacement of fossil fuels with a more sustainable type. Succinic acid is a promising renewable material that can react with ethylene glycol and 1,4‐butanediol in a two‐step polycondensation reaction to form hydroxylated polyesters. Copolymerization reactions were investigated to produce novel green binders for manufacture of solid propellants. The ester of the first step of polycondensation was used as a plasticizer in the propellant formulation. These products can be an alternative to binders of fossil sources, such as hydroxyl‐terminated polybutadiene (HTPB), frequently used as fuel of commercial propellants. Initially, analyses of Fourier transform infrared spectroscopy, nuclear magnetic resonance and gel permeation chromatography indicated the formation of polymeric products and adequate chain growth at reaction conditions. Then, the obtained copolymers were characterized by rheological analyses, which revealed that the processability of the copolymer materials was similar to that of the HTPB samples. Additionally, thermogravimetric analyses indicated that the copolymers presented good thermal stability below 200°C. Furthermore, differential scanning calorimetric (DSC) analyses indicated that the glass transition temperatures of the obtained copolymer samples ranged from −20 to −60°C, a suitable range for the intended use. Solid propellants were then prepared with solid loadings above 70 wt %, heat of combustion above 11,300 J g−1 and heat of explosion above 4,980 J g−1, which are compatible with values expected for solid propellants. Finally, oxygen balance calculations showed that the intrinsic oxygen content of the polyesters can allow the reduction of amounts of oxidizers in the final propellants.

Design and in vitro/in vivo evaluation of chitosan-polyvinyl alcohol copolymer material cross-linked by dynamic borate ester covalent for pregabalin film-forming delivery system

This research introduced a novel polymer synthesized by combining chitosan and modified polyvinyl alcohol, cross-linked with boric acid using dynamic covalent bonds. The polymer was developed to formulate a pregabalin Film-forming system (FFS) for treating postherpetic neuralgia via topical application, showcasing notable skin adhesion and drug delivery properites. The chitosan-boric acid-modified polyvinyl alcohol polymer was analyzed using NMR, FTIR. The exceptional features of the optimized FFS were evaluated through rheometer, Differential scanning calorimetry (Tg = 45.98 °C), contact angle (θ = 78.62°). The elongation (60.05 ± 3.67 %), cohesion (56.94 ± 4.65 MPa) and skin adhesion (58.12 ± 2.99 kPa) of chitosan-boric acid-modified polyvinyl alcohol were found to be 5.2, 6.8, and 8.3 times higher than those of the pure chitosan film, attributed to the double network structure formed by the cross-linked reversible dynamic covalent bond. The optimized pregabalin FFS exhibited increased in vitro (86.25 ± 1.87 μg/g) and in vivo (100.42 ± 7.44 μg/g) skin retention amounts compared to in vivo oral administration (28.43 ± 4.61 μg/g). In summary, the utilization of borate ester dynamic covalent bonds in developing chitosan-based film-forming polymer proved beneficial in improving skin adhesion and topical therapeutic effectiveness, thereby mitigating the risk of systemic side effects associated with oral administration.

Fungal Attachment-Resistant Polymers for the Additive Manufacture of Medical Devices.

This study reports the development of the first copolymer material that (i) is resistant to fungal attachment and hence biofilm formation, (ii) operates via a nonkilling mechanism, i.e., avoids the use of antifungal actives and the emergence of fungal resistance, (iii) exhibits sufficient elasticity for use in flexible medical devices, and (iv) is suitable for 3D printing (3DP), enabling the production of safer, personalized medical devices. Candida albicans (C. albicans) can form biofilms on in-dwelling medical devices, leading to potentially fatal fungal infections in the human host. Poly(dimethylsiloxane) (PDMS) is a common material used for the manufacture of medical devices, such as voice prostheses, but it is prone to microbial attachment. Therefore, to deliver a fungal-resistant polymer with key physical properties similar to PDMS (e.g., flexibility), eight homopolymers and 30 subsequent copolymers with varying glass transition temperatures (Tg) and fungal antiattachment properties were synthesized and their materials/processing properties studied. Of the copolymers produced, triethylene glycol methyl ether methacrylate (TEGMA) copolymerized with (r)-α-acryloyloxy-β,β-dimethyl-γ-butyrolactone (AODMBA) at a 40:60 copolymer ratio was found to be the most promising candidate by meeting all of the above criteria. This included demonstrating the capability to successfully undergo 3DP by material jetting, via the printing of a voice prosthesis valve-flap using the selected copolymer.

Partially Bio-Based and Biodegradable Poly(Propylene Terephthalate-Co-Adipate) Copolymers: Synthesis, Thermal Properties, and Enzymatic Degradation Behavior.

A series of partially bio-based and biodegradable poly(propylene terephthalate-co-adipate) (PPTA) random copolymers with different components were prepared by the melt polycondensation of petro-based adipic acid and terephthalic acid with bio-based 1,3-propanediol. The microstructure, crystallization behavior, thermal properties, and enzymatic degradation properties were further investigated. The thermal decomposition kinetics was deeply analyzed using Friedman's method, with the thermal degradation activation energy ranging from 297.8 to 302.1 kJ/mol. The crystallinity and wettability of the copolymers decreased with the increase in the content of the third unit, but they were lower than those of the homopolymer. The thermal degradation activation energy E, carbon residue, and reaction level n all showed a decreasing trend. Meanwhile, the initial thermal decomposition temperature (Td) was higher than 350 °C, which can meet the requirements for processing and use. The PPTA copolymer material still showed excellent thermal stability. Adding PA units could regulate the crystallinity, wettability, and degradation rate of PPTA copolymers. The composition of PPTA copolymers in different degradation cycles was characterized by 1H NMR analysis. Further, the copolymers' surface morphology during the process of enzymatic degradation also was observed by scanning electron microscopy (SEM). The copolymers' enzymatic degradation accorded with the surface degradation mechanism. The copolymers showed significant degradation behavior within 30 days, and the rate increased with increasing PA content when the PA content exceeded 45.36%.

Ultrasound-assisted dispersive micro solid phase extraction of maneb in water and food samples with new hybrid block copolymer material prior to micro-spectrophotometric analysis

A simple and effective ultrasound-assisted dispersive micro solid-phase extraction (UA-dμSPE) method was developed for the spectrophotometric determination of traces maneb in food and water. In this study, a new hybrid block copolymer poly (vinyl benzyl chloride-b-dimethyl aminoethyl methacrylate) (Pvb-DMA) was synthesized and characterized using techniques such as FTIR, SEM-EDX. The synthesized Pvb-DMA was used as an adsorbent for the extraction of maneb for first time in this study. The effects of different experimental variables such as pH, adsorbent amount, sample volume, eluent type were optimized. The statistical toll factorial design was applied to estimate the individual and combined impact of parameters on the extraction of maneb. The applicability of different solvents such as acetone, methanol, ethanol, tetrahydrofuran, acetonitrile for maneb recovery from adsorbent was tested. The detection and quantification limits were found to be 3.3 ng mL−1 and 10.0 ng mL−1, respectively. In addition, the preconcentration factor and linear range was obtained 300 and 10–500 ng mL−1. The extraction recovery and relative standard deviation were found to be 95 % and 2.8 %, respectively.

Selective Clearance of Circulating Histones Based on Dodecapeptide-Grafted Copolymer Material for Sepsis Blood Purification.

Sepsis is defined as a life-threatening organ dysfunction caused by a dysregulated host response to infection. Research indicates that circulating histones, as pathogenic factors, may represent a therapeutic target for sepsis. However, effectively clearing circulating histones poses a challenge due to their structural similarity to normal blood proteins, their low abundance in the bloodstream, and serious interference from other blood biomacromolecules. Here we design a dodecapeptide-based functional polymer that can selectively adsorb circulating histones from the blood. The peptide, named P1 (HNHHQLALVESY), was discovered through phage display screening and demonstrated a strong affinity for circulating histones while exhibiting negligible affinities for common proteins in the blood, such as human serum albumin (HSA), immunoglobulin G (IgG), and transferrin (TRF). Furthermore, the P1 peptide was incorporated into a functional polymer design, poly(PEGMA-co-P1), which was immobilized onto a silica gel surface through reversible addition-fragmentation chain transfer polymerization. The resulting material was characterized using solid nuclear magnetic resonance, thermogravimetric analysis, and X-ray photoelectron spectroscopy. This material demonstrated the ability to selectively and efficiently capture circulating histones from both model solutions and whole blood samples while also exhibiting satisfactory blood compatibility, good antifouling properties, and resistance to interference. Satisfactory binding affinity and efficient capture capacity toward histone were also observed for the other screened peptide P2 (QMSMDLFGSNFV)-grafted polymer, validating phage display as a reliable ligand screening strategy. These findings present an approach for the specific clearance of circulating histones and hold promise for future clinical applications in blood purification toward sepsis.

Electrochemical synthesis of poly(6,7-diphenyl-4,9-di(selenophen-2-yl)-[1,2,5]thiadiazolo[3,4-g]quinoxaline-co-3,3-didecyl-3,4-propylenedioxythiophene) and its electrochemical and optical characterizations

In this study, electrochemical copolymerization of 6,7-diphenyl-4,9-di(selenophen-2-yl)-[1,2,5]thiadiazolo[3,4-g]quinoxaline and 3,3’-didecyl-3,4-propylenedioxythiophene is carried out to obtain a copolymer namely poly(6,7-diphenyl-4,9-di(selenophen-2-yl)-[1,2,5]thiadiazolo[3,4-g]quinoxaline-co-3,3’-didecyl-3,4-propylenedioxythiophene). Two distinct copolymers, PC1 and PC2, were produced as a result of the utilization of two different feed ratios. Copolymers were examined electrochemically and spectroelectrochemically after the copolymerization procedure. This study’s major goal is to combine the exceptional characteristics of homopolymers P1 and P2 (P1 has a low band gap but is not soluble, and P2 is soluble and has a larger band gap) into a single copolymeric material.

Design of chiral acidic molecularly imprinted polymer for the enantioselective separation of (±)‐DOPA

AbstractBackgroundThe study focuses on developing a stable enantioselective matrix for the efficient chiral identification and enantioresolution of l‐DOPA and (±)‐DOPA. The matrix is derived from a copolymeric material made from poly[(vinylsulfonic acid)‐co‐(4‐vinylpyridine)] crosslinked with divinylbenzene.Resultsl‐DOPA‐vinylsulfonamide was synthesized and characterized. This chiral sulfonamide was copolymerized with 4‐vinylpyridine in the presence of a divinylbenzene crosslinker, using azobisisobutyronitrile as a thermal initiator. Post‐polymerization, the polymeric particles were treated with NaOH and subsequently washed with acid to remove the integrated l‐DOPA species. Scanning electron microscopy and Fourier transform infrared spectroscopy confirmed the imprinted l‐DOPA‐IP particles. The manufactured l‐DOPA‐IP demonstrated a tenfold greater affinity for l‐DOPA compared to d‐DOPA. Langmuir adsorption experiments at pH 6 showed a maximum capacity of 162 mg g−1. Enantiomeric excess values for l‐ and d‐DOPA, determined through optical separation using a column approach, were 94% and 82%, respectively, in the loading and recovery solutions.ConclusionThe developed copolymeric material effectively served as an enantioselective matrix, exhibiting high selectivity and capacity for l‐DOPA. The process demonstrated efficient chiral identification and separation, achieving significant enantiomeric excess values for both l‐ and d‐DOPA. © 2024 Society of Chemical Industry (SCI).

Analyzing the Thermal Characteristics of Three Lining Materials for Plantar Orthotics.

The choice of materials for covering plantar orthoses or wearable insoles is often based on their hardness, breathability, and moisture absorption capacity, although more due to professional preference than clear scientific criteria. An analysis of the thermal response to the use of these materials would provide information about their behavior; hence, the objective of this study was to assess the temperature of three lining materials with different characteristics. The temperature of three materials for covering plantar orthoses was analyzed in a sample of 36 subjects (15 men and 21 women, aged 24.6 ± 8.2 years, mass 67.1 ± 13.6 kg, and height 1.7 ± 0.09 m). Temperature was measured before and after 3 h of use in clinical activities, using a polyethylene foam copolymer (PE), ethylene vinyl acetate (EVA), and PE-EVA copolymer foam insole with the use of a FLIR E60BX thermal camera. In the PE copolymer (material 1), temperature increases between 1.07 and 1.85 °C were found after activity, with these differences being statistically significant in all regions of interest (p < 0.001), except for the first toe (0.36 °C, p = 0.170). In the EVA foam (material 2) and the expansive foam of the PE-EVA copolymer (material 3), the temperatures were also significantly higher in all analyzed areas (p < 0.001), ranging between 1.49 and 2.73 °C for EVA and 0.58 and 2.16 °C for PE-EVA. The PE copolymer experienced lower overall overheating, and the area of the fifth metatarsal head underwent the greatest temperature increase, regardless of the material analyzed. PE foam lining materials, with lower density or an open-cell structure, would be preferred for controlling temperature rise in the lining/footbed interface and providing better thermal comfort for users. The area of the first toe was found to be the least overheated, while the fifth metatarsal head increased the most in temperature. This should be considered in the design of new wearables to avoid excessive temperatures due to the lining materials.

Nickel‐ and Palladium‐Catalyzed Copolymerizations of Norbornene with Polar α‐Olefins

AbstractRecent progress regarding the copolymerization of norbornene with various polar α‐olefins catalyzed by nickel and palladium catalysts is reviewed here with special attention paid to the diverse catalyst frameworks, polar monomer scopes as well as polymer microstructures. Both the influences of steric effect and electron property of ligand substituents and the type of polar monomers on the catalytic behaviors (activity, stability, polarity tolerance, etc.) and the polymer microstructures (molecular weight and distribution, comonomer contents, etc.) have been summarized. The introduction of noncyclic‐olefins, such as polar vinyl monomers, polar higher α‐olefins, and polar styrenes, into rigid cyclic‐based polynorbornene chain resulted in significant modifications on the polarity, compatibility, thermostability, processibility, transparency, and many other properties of the material, which has also been discussed in the review. The contents of this review have been classified according to the type of polar monomers involved in the norbornene copolymerization, and each section included nickel and palladium catalysts bearing different ligand structures, which will be meaningful for the development of new types of catalysts and new families of norbornene‐based cyclic olefin copolymer materials in the future.

Review of the feasibility of a new touch-sensitive digital display enabled by block copolymer materials

Nowadays, electronic devices are widely used, and as an important part of many electronic devices, human-computer interaction displays have a lot of room for development. At present, traditional touch displays typically incorporate materials such as indium tin oxide (ITO) or graphene, which have limitations such as inflexibility, average accuracy and needing external power supplies. This article describes a motion sensor without additional power supply, which is based on one-dimensional photonic crystals of interpenetrating hydrogel network block copolymer (IHN-BCP), composed of photonic crystals alternating between different layers. The article concentrates on the viability of addressing these difficulties. The result shows that Block copolymers are unique polymers consisting of two or more distinct polymer chains, with the potential to exhibit self-assembling behaviour. Due to the special properties of block copolymer, this display could have flexible substrates and detect various contact and non-contact human motions. This device can be applied to interactive screens for cell phone screens, factory equipment, and other electronic products, and can also provide a reference for the future development of flexible screens.

Enantioselective separation of (±)‐epinephrine by chiral acidic molecularly imprinted polymer

AbstractIn this study, we look into how poly[(4‐styrenesulfonic acid)‐co‐(4‐vinylpyridine)] crosslinked with divinylbenzene can be used as a copolymeric material to effectively recognize l‐epinephrine (L‐EP) and chirally separate (±)‐EP. It was first possible to synthesize and analyze L‐EP‐styrene‐4‐sulfonamide (L‐EP‐SSA). The resulting chiral sulfonamide was used to copolymerize with a 4‐vinylpyridine–divinylbenzene mixture. The integrated L‐EP species were removed by heating the polymer materials under strong alkaline conditions to degrade the sulfonamide links, followed by acidification in HCl solution. The imprinted L‐EP‐IP materials were analyzed using Fourier transform infrared spectroscopy and scanning electron microscopy. The produced L‐EP‐IP displayed selectivity characteristics indicative of an affinity for L‐EP almost eleven times higher than that for d‐epinephrine (D‐EP). At a pH of 7, Langmuir adsorption experiments demonstrated a maximal capacity of 165 mg g−1. Following optical separation by means of a column method, enantiomeric excess levels of L‐ and D‐EP in the initial feeding and subsequent recovering solutions were calculated to be 93% and 80%, respectively. © 2024 Society of Industrial Chemistry.

Recent advances of copolymer for water treatment.

Increasing water pollution due to anthropogenic activities prompts the quest for an effective water treatment method. Polymeric materials have gained attention as adsorbents for water purification. Membranes are majorly made from homopolymeric materials. However, recent studies have focused on using copolymeric materials for improved performance. In this review, the basics of copolymerization including various types of copolymers, synthetic approaches, and their applications in various water pollutants removal are discussed in detail. Advances in water treatment technology using copolymeric materials as adsorbent/membranes in the last 4 years are covered with insights into the future outlook and areas of improvement in terms of copolymer composites for water treatment. Studies from the literature did not only reveal effectiveness of copolymer as a flocculant/antifouling materials and in removal of selective toxic metals, oil, and microbes but also demonstrated recyclability of the copolymer sorbents/membrane. Full exploration of unique copolymer textural and structural properties could lead to great advancement in water treatment process. PRACTITIONER POINTS: The copolymer types and synthetic methods are discussed. Application of copolymer as adsorbent/membranes for water treatment is presented. Recent advances show good pollutants removal for toxic metals, oil, and organics. Copolymer composites have great potential as adsorbent/membranes for future use in water treatment processes.

Zwitterionic functionalization of polysaccharide gum by graft copolymerization to develop 3-D network materials for anticancer drug delivery applications

Herein, functionalization of polysaccharide gum has been carried out to develop network copolymeric materials for use in sustained anticancer drug delivery. Grafting reaction of poly[2-(methacryloyloxy)ethyl] dimethyl-(3-sulfopropyl)ammonium hydroxide (MEDSAH) onto sterculia gum has been done in the presence of crosslinker. Copolymeric materials were characterized by scanning electron micrographs (SEMs), atomic force microscopy (AFM), Fourier transform infrared spectroscopy (FTIR), X-ray diffraction (XRD), 13C-nuclear magnetic resonance (NMR), and thermogravimetric analysis (TGA). SEM, AFM and XRD displayed heterogeneous morphology with a rough surfaces of amorphous copolymeric materials. Peaks at 173.822 ppm (carbonyl carbon) and at 60.653 ppm (methylene carbon attached to a quaternary ammonium group) confirmed the addition of poly(MEDSAH) during the grafting reaction. Mesh size in network hydrogel was found between 14.54 nm to 36.32 nm. Sustained release of doxorubicin was found with non-Fickian diffusion and was best demonstrated by the kinetic model Hixson Crowell. The biocompatibility of material was revealed in a haemolytic index (1.74 ± 0.26%) less than two percent during the copolymer-blood interaction. The material exhibited antioxidant and mucoadhesion properties. Free radical scavenging ability of copolymers was 49.41 ± 0.97% in 2,2-diphenyl-1-picrylhydrazyl (DPPH) assay of the antioxidant test. These properties of copolymeric hydrogels demonstrated their suitability for use in sustained drug delivery systems for cancer chemotherapy.

Large strain micromechanics of thermoplastic elastomers with random microstructures

Thermoplastic polyurethanes (TPU) are block copolymeric materials composed of plastomeric “hard” and elastomeric “soft” domains, by which they exhibit highly resilient yet dissipative large deformation features depending on volume fractions and microstructures of the two distinct domains. Here, we develop a new methodology to explore the microscopic deformation mechanisms in TPU materials with highly disordered microstructures. We propose new micromechanical models for randomly dispersed (or occluded) as well as randomly continuous hard domains (and mixtures of both dispersed and continuous hard domains), each within a continuous soft structure as widely found in representative TPU materials over a wide range of volume fractions, vhard = 26.9% to 52.2%. The micromechanical modeling results are compared to experimental data on the macroscopic large strain behaviors reported previously (Cho et al., 2017). We explore the role of the dispersed vs. continuous nature of the geometric features of the random microstructures on shape recovery and energy dissipation at the microstructural level in these phase-separated copolymeric materials.

Advanced analysis of ethylene vinyl acetate copolymer materials for photovoltaic modules

Ethylene vinyl acetate (EVA) copolymers are commonly used as encapsulation material and as adhesive layer for backsheet laminates of photovoltaic (PV) modules. While Fourier-Transform Infrared spectroscopy (FTIR) and Differential Scanning Calorimetry (DSC) are well established to analyse EVA encapsulants in PV modules, X-ray Photoelectron Spectroscopy (XPS) is seldomly used. Hence, the objective of this paper was to evaluate the potential and limitations of XPS for advanced analysis and testing of EVA encapsulants. Consequently, EVA grades of different vinyl acetate (VA) comonomer content were characterized and evaluated systematically by XPS, FTIR and DSC. Independent on the analytic technique linear relationships between the obtained values and VA contents were confirmed. Slightly higher VA contents on the surface deduced by XPS were attributed to a surface layer rich of amorphous phase material. In addition, XPS analysis of peroxide modified encapsulants with a VA comonomer content of 30.2 wt% revealed a higher carbon content on the surface after crosslinking. Hence, it is proposed that peroxide crosslinking is associated with deacetylation and the subsequent release of low molar mass decomposition products. Overall, the exceptional surface sensitivity of XPS was clearly confirmed for analysis and testing of EVA grades, highlighting the potential of the method for further degradation and interaction studies of components of PV modules.

Blending Modification Technology of Insulation Materials for Deep Sea Optoelectronic Composite Cables

The insulation layer of deep-sea optoelectronic composite cables in direct contact with high-pressure and highly corrosive seawater is required for excellent water resistance, environmental stress cracking resistance (ESCR), and the ability to withstand high DC voltage. Although high-density polyethylene (HDPE) displays remarkable water resistance, it lacks sufficient resistance to environmental stress cracking (ESCR). This article is based on a blend modification approach to mixing HDPE with different vinyl copolymer materials (cPE-A and cPE-B). The processing performance and mechanical properties of the materials are evaluated through rheological and mechanical testing. The materials’ durability in working environments is assessed through ESCR tests and water resistance experiments. Ultimately, the direct current electrical performance of the materials is evaluated through tests measuring space charge distribution, direct current resistivity, and direct current breakdown strength. The results indicate that, in the polyethylene blend system, the rheological properties and ESCR characteristics of HDPE/cPE-A composite materials did not show significant improvement. Further incorporation of high melt index linear low-density polyethylene (LLDPE) material not only meets the requirements of extrusion processing but also exhibits a notable enhancement in ESCR performance. Meanwhile, copolymerized polyethylene cPE-B, with a more complex structure, proves effective in toughening HDPE materials. The material’s hardness significantly decreases, and when incorporating cPE-B at a level exceeding 20 phr, the composite materials achieve excellent ESCR performance. In a simulated seawater environment at 50 MPa, the water permeability of all co-modified composite materials remained below 0.16% after 120 h. The spatial charge distribution and direct current resistivity characteristics of the HDPE, cPE-A, and LLDPE composite systems surpassed those of the HDPE/cPE-B materials. However, the HDPE/cPE-B composite system exhibited superior dielectric strength. The application of composite materials in deep-sea electro–optical composite cables is highly promising.

Chiral acidic molecularly imprinted polymer for enantio-separation of norepinephrine racemate.

We are looking into how well a copolymeric material made of poly (maleic acid-co-4-vinylpyridine) cross-linked with divinylbenzene can separate L-norepinephrine (L-NEP) from (±)-NEP. The initial step in this direction was the synthesis and subsequent analysis of L-NEP-maleimide chiral derivative. A 4-vinylpyridine/divinylbenzene combination was copolymerized with the resultant chiral maleimide. After heating the polymer materials in a high-alkaline environment to breakdown the connecting imide bonds, they were acidified in an HCl solution to eliminate the incorporated L-NEP species. Fourier transform infrared spectroscopy (FTIR) and a scanning electron microscope were used to examine the imprinted L-NEP-imprinted materials. The manufactured L-NEP-imprinted materials exhibited selectivity characteristics that were over 11 times greater for L-NEP than D-norepinephrine. The highest capacity observed in Langmuir adsorption studies was 170 mg/g at a pH of 7. After optical separation using a column technique, it was determined that the enantiomeric excess levels of D-norepinephrine and L-NEP in the first feeding and subsequent recovery solutions were 95% and 81%, respectively.