Copolymer Surface Research Articles

The Energy Characteristics of the Surface of Statistical Copolymers.

The results of systematic studies on the surface energy γ and its polar γP and dispersion γD components of statistical copolymers of styrene and butadiene, acrylonitrile and butadiene, and butyl acrylate and vinyl acetate, with regard to their thermal prehistory, are generalized. Along with copolymers, the surfaces of their composing homopolymers were examined. We obtained the energy characteristics of the adhesive surfaces of copolymers that contacted with air, high-energy aluminium Al (γ = 160 mJ/m2), and the low-energy substrate surface of polytetrafluoroethylene F4 (PTFE) (γ = 18 mJ/m2). The surfaces of copolymers in contact with air, aluminium, and PTFE were investigated for the first time. It was found that the surface energy of these copolymers tended to occupy an intermediate value between the surface energy of the homopolymers. The additive nature of the change in the surface energy of the copolymers with their composition, as previously established in the works of Wu, extends to the dispersive component of the free surface energy γD and the critical surface energy γcr, according to Zisman. It was shown that a significant influence on the adhesive activity of copolymers was exerted by the substrate surface upon which the adhesive was formed. Thus, for the butadiene-nitrile copolymer (BNC) samples formed in contact with a high-energy substrate, their surface energy growth was associated with a significant increase in the polar component of the surface energy γP from 2 mJ/m2 for the samples formed in contact with air, to an increase from 10 to 11 mJ/m2 for the samples formed in contact with Al. The reason why the interface influenced the change in the energy characteristics of the adhesives was the selective interaction of each macromolecule fragment with the active centres of the substrate surface. As a result, the composition of the boundary layer changed and it became enriched with one of the components. The structure of such layers is nonequilibrium. The thermal annealing of copolymers in the mode of a stepwise temperature increase led to a convergence in the values of γ, asymptotically tending to the value characteristic of the surface of the copolymers formed in air. The activation energies for the processes of the conformational rearrangements of the macromolecules in the surface layers of the copolymers were calculated. It was found that the conformational rearrangements of the macromolecules in the surface layers occurred as a result of the internal rotation of the functional groups that determined the polar component of the surface energy.

Cell Spheroid Formation on the Surface of Multi-Block Copolymers Composed of Poly(2-methoxyethyl acrylate) and Polyethylene Glycol.

3D structured cells have great drug screening potential because they mimic in vivo tissues better than 2D cultured cells. In this study, multi-block copolymers composed of poly(2-methoxyethyl acrylate) (PMEA) and polyethylene glycol (PEG) are developed as a new kind of biocompatible polymers. PEG imparts non-cell adhesion while PMEA acts as an anchoring segment to prepare the polymer coating surface. The multi-block copolymers show higher stability in water than PMEA. A specific micro-sized swelling structure composed of a PEG chain is observed in the multi-block copolymer film in water. A single NIH3T3-3-4 spheroid is formed in 3h on the surface of the multi-block copolymers with 8.4 wt% PEG. However, at a PEG content of 0.7 wt%, spheroid formed after 4 days. The adenosine triphosphate (ATP) activity of cells and the internal necrotic state of the spheroid change depending on PEG loading in the multi-block copolymers. As the formation rate of cell spheroid on low-PEG-ratio multi-block copolymers is slow, internal necrosis of cell spheroid is less likely to occur. Consequently, the cell spheroid formation rate by changing the PEG chain content in multi-block copolymers is successfully controlled. These unique surfaces are suggested to be useful for 3D cell culture.

Formation behavior of monolayers on the water surface of water-soluble thermoplastic and insoluble-thermosetting copolymers with hyperbranched units containing s-benzenetricarbamide cores

The formation and structure of Langmuir monolayers and Langmuir-Blodgett films were studied using water-soluble polymers, which have difficulty forming monolayers on the water surface, and polymers that are insoluble in all solvents. The network copolymers consisting of hyperbranched units with an s-benzenetricarbamide core used in this study can be freely controlled by azidation/non-azidation of both ends of the hard segment. The water-soluble copolymer, which exhibits the properties of a thermoplastic resin, can form a monolayer when spread on the water surface at a low temperature at which the solubility decreases. Even when the subphase temperature increased, no significant change in the monolayer behavior of the thermoplastic copolymer was observed. This behavior was attributed to the formation of an insoluble single-particle layer with hydrophilic groups facing inward on the water surface. The insoluble copolymer, which exhibits thermosetting properties, forms a tablet that floats on the water surface for an extended period. The surface pressure-time isotherms showed the formation of a monolayer from the tablet over time, and it was possible to measure the surface pressure-area isotherms by two-dimensional compression after a certain period of time.

Synthesis and Characterization of Poly(methyl methacrylate-co-vinyl triethoxysilane) Prepared by Free Radical Polymerization

The copolymerization of methyl methacrylate (MMA) with vinyl triethoxysilane (VTES) was carried out in ethyl cellosolve at 70 ℃ using azobisisobutyronitrile (AIBN) as a free radical initiator. The prepared copolymer was purified and then analysed by FT-IR, NMR, TGA and SEM analyses. FT-IR along with NMR confirm the successful preparation of the copolymer. The prepared copolymer shows better thermal stability than poly(methyl methacrylate). A morphological study was also carried out by SEM analysis. SEM micrographs show that the copolymer surface gets roughened and becomes porous on copolymerization.

Anionic polymerization and transport of diethyl methylidene malonate on polyolefin copolymer surfaces

Initiator concentration impacts monomer transport rate. Grafting from substrates with minimal surface treatment.

Co-polymerisation of furfuryl alcohol for furan resins with increased toughness

• Various furfuryl alcohol copolymers were synthesized. • Copolymerization showed improved mechanical strength. • Fracture surface of copolymers show ductility. Furfuryl alcohol resins with a varying amount of comonomer inhibiting the conjugation and crosslinking reactions of the resin are synthesised. The pre-resins are briefly characterised to ensure their properties besides composition are similar. Afterwards the pre-resins are cured and their mechanical properties are investigated. There was a markable increase in strength and strain to failure of the cured resin upon addition of 5% DMFA.

Biomimetic Antidote Nanoparticles: a Novel Strategy for Chronic Heavy Metal Poisoning.

Chronic lead poisoning has become a major factor in global public health. Chelation therapy is usually used to manage lead poisoning. Dimercaptosuccinic acid (DMSA) is a widely used heavy metal chelation agent. However, DMSA has the characteristics of poor water solubility, low oral bioavailability, and short half-life, which limit its clinical application. Herein, a long-cycle slow-release nanodrug delivery system was constructed. We successfully coated the red blood cell membrane (RBCM) onto the surface of dimercaptosuccinic acid polylactic acid glycolic acid copolymer (PLGA) nanoparticles (RBCM-DMSA-NPs), which have a long cycle and detoxification capabilities. The NPs were characterized and observed by particle size meters and transmission electron microscopy. The results showed that the particle size of RBCM-DMSA-NPs was approximately 146.66 ± 2.41nm, and the zeta potential was - 15.34 ± 1.60mV. The homogeneous spherical shape and clear core-shell structure of the bionic nanoparticles were observed by transmission electron microscopy. In the animal tests, the area under the administration time curve of RBCM-DMSA-NPs was 156.52 ± 2.63 (mg/L·h), which was 5.21-fold and 2.36-fold that of free DMSA and DMSA-NPs, respectively. Furthermore, the median survival of the RBCM-DMSA-NP treatment group (47days) was 3.61-fold, 1.32-fold, and 1.16-fold for the lead poisoning group, free DMSA, and DMSA-NP groups, respectively. The RBCM-DMSA-NP treatment significantly extended the cycle time of the drug in the body and improved the survival rate of mice with chronic lead poisoning. Histological analyses showed that RBCM-DMSA-NPs did not cause significant systemic toxicity. These results indicated that RBCM-DMSA-NPs could be a potential candidate for long-term chronic lead exposure treatment.

Ferrocene-Based Terpolyamides and Their PDMS-Containing Block Copolymers: Synthesis and Physical Properties

Aromatic polyamides are well-known as high-performance materials due to their outstanding properties making them useful in a wide range of applications. However, their limited solubility in common organic solvents restricts their processability and becomes a hurdle in their applicability. This study is focused on the synthesis of processable ferrocene-based terpolyamides and their polydimethylsiloxane (PDMS)-containing block copolymers, using low-temperature solution polycondensation methodology. All the synthesized materials were structurally characterized using FTIR and 1H NMR spectroscopic techniques. The ferrocene-based terpolymers and block copolymers were soluble in common organic solvents, while the organic analogs were found only soluble in sulfuric acid. WXRD analysis showed the amorphous nature of the materials, while the SEM analysis exposed the modified surface of the ferrocene-based block copolymers. The structure-property relationship of the materials was further elucidated by their water absorption and thermal behavior. These materials showed low to no water absorption along with their high limiting oxygen index (LOI) values depicting their good flame-retardant behavior. DFT studies also supported the role of various monomers in the polycondensation reaction where the electron pair donation from HOMO of diamine monomer to the LUMO of acyl chloride was predicted, along with the calculation of various other parameters of the representative terpolymers and block copolymers.

Wettability of soft PLGA surfaces predicted by experimentally augmented atomistic models

A challenging topic in surface engineering is predicting the wetting properties of soft interfaces with different liquids. However, a robust computational protocol suitable for predicting wettability with molecular precision is still lacking. In this article, we propose a workflow based on molecular dynamics simulations to predict the wettability of polymer surfaces and test it against the experimental contact angle of several polar and nonpolar liquids, namely water, formamide, toluene, and hexane. The specific case study addressed here focuses on a poly(lactic-co-glycolic acid) (PLGA) flat surface, but the proposed experimental-modeling protocol may have broader fields of application. The structural properties of PLGA slabs have been modeled on the surface roughness determined with microscopy measurements, while the computed surface tensions and contact angles were validated against standardized characterization tests, reaching a discrepancy of less than 3% in the case of water. Overall, this work represents the initial step toward an integrated multiscale framework for predicting the wettability of more complex soft interfaces, which will eventually take into account the effect of surface topology at higher scales and synergically be employed with experimental characterization techniques.Impact statementControlling the wettability of surfaces has important implications for energy (e.g., self-cleaning solar panels), mechanical (e.g., enhanced heat transfer), chemical (e.g., fluids separation), and biomedical (e.g., implants biocompatibility) industries. Wetting properties arise from a combination of chemical and physical features of surfaces, which are inherently intertwined and multiscale. Therefore, tailoring wettability to target functionalities is a time-intensive process, especially if relying on a trial-and-error approach only. This becomes even more challenging with soft materials, since their surface configuration depends on the solid-liquid interactions at the molecular level and could not be defined a priori. The improved accuracy of atomistic models allows detailing how the effective properties of materials arise from their nanoscale features. In this article, we propose and validate a new molecular dynamics protocol for assessing the wettability of soft interfaces with polar and nonpolar liquids. The prediction capabilities of simulations are augmented by a close comparison with microscopy and contact angle experiments. Since smooth copolymer surfaces are considered, here the effort mainly focuses on the effect of chemical features on wettability. In perspective, the proposed atomistic in silico approach could be coupled with computational models at higher scales to include the effect of surface microstructures, eventually easing the development of multi-scale surfaces with tunable wettability.Graphical abstract

Novel negatively-charged amphiphilic copolymers of PVDF-g-PAMPS and PVDF-g-PAA to improve permeability and fouling resistance of PVDF UF membrane

Novel negatively charged polyvinylidene fluoride (PVDF) membranes containing amphiphilic copolymer additives: PVDF-g-2-acrylamido-2-methylpropane sulfonic acid (PVDF-g-PAMPS) and PVDF-g-acrylic acid (PVDF-g-PAA) were synthesized via the phase inversion method. The formation of functional groups and chemical composition of the synthesized amphiphilic copolymers ((PVDF-g-PAMPS) and (PVDF-g-PAA)) were investigated by Fourier transform infrared (FTIR) spectroscopy and 1H nuclear magnetic resonance (1H NMR) spectroscopy. The characterization of the copolymerized blended membranes ((PVDF-g-PAMPS/PVDF) and (PVDF-g-PAA/PVDF)) were investigated by using ATR-FTIR, SEM, AFM, porosity, mean pore radius, water contact angle, zeta potential, and mechanical stability techniques. The membrane hydrophilicity and antifouling performance of the copolymerized membranes were evaluated using the filtration performance. It was found that the negatively charged modified membranes with 10 wt% PVDF-g-PAMPS and 10 wt% PVDF-g-PAA presented a significant pure water flux (181.6 and 336.7 L/m2h, respectively at 0.2 MPa) and an outstanding flux recovery ratio (FRR) (up to 100%) in comparison with the original PVDF (97.5 L/m2h and 74%). Besides, the surface zeta potential of the copolymerized membranes confirmed noteworthy negatively charged in the copolymer surface, which showed better performance of BSA protein and Direct Red 23 dye rejection capability of 100% and more than 99%, respectively. The strong synergetic impacts of hydrogen bonding and the electrostatic repulsion of negatively charged grafted sulfonic and carboxylic groups against protein foulants were ascribed to the increased performance of the copolymerized blended membranes.

Facile plasma grafting of zwitterions onto nanofibrous membrane surface for improved antifouling properties and filtration performance

To improve the permeability and antifouling properties of filtration membrane, zwitterionic sulfobetaine methacrylate (SBMA) was introduced onto the surface of ethylene vinyl alcohol copolymer (EVOH) nanofibrous membrane (NFM) via facile spray-coating followed by plasma treatment method. Surface chemical compositions, morphology, pore size distribution, roughness, zeta potential, hydrophilicity, permeability, separation performance, antifouling and mechanical properties of the pristine EVOH nanofibrous membrane, plasma treated membrane (PNFM) and the SBMA modified membrane (PZNFM) were systematically characterized and compared. Due to the improved hydrophilicity and antifouling properties, PZNFM showed higher water permeability (i.e. 9426.7 L h−1 m−2, 0.2 MPa), lower bovine serum albumin (BSA) adsorption (i.e. 0.15%), and higher flux recovery ratio (i.e. 95.65%) compared with the original NFM. Meanwhile, the newly prepared zwitterionic membrane can separate and intercept of E. coli, S. aureus and Brevundimonas dimimuta absolutely. The mutiphysical-chemical properties of the membrane allow it to function with synergy between permeability and sterile filtration efficiency for further bacterial separation and interception application. Our work provides a simple and scalable method to fabricate sterile membrane with outstanding performance, highlighting its great potential in sterile filtration.

Micro-Nano Dual-Scale All-Polymer particles for construction of superwetting surface with controllable wettability and Hot-Water-Repellency

Based on the principle of like dissolves like, the reactive oil phases, consisted of monomers, cross-linked monomers, fluorinated monomers and initiators, were absorbed into cavity of hollow polymer microspheres to obtain reactants-loaded particles in the stirring condition at room temperature; in the effect of heating, the internal reactants could polymerize to glut its core cavity and shell pores, hereupon a quantity of nanoscale copolymer surface protrusions were produced; ultimately, the micro-nano dual-scale all-polymer particles (MNDPs) were integrally formed by dispensing with any chemical modification, which physico-chemical properties could be regularly controlled by utilizing alteration of absorbed fluorinated monomers types. In view of the special wetting behaviour for various temperature water droplets to anti-wetting MNDPs-based surfaces, the superhydrophobic fabric, applicable to anti-fouling and self-cleaning, was prepared by coating with short fluoroalkyl chain-containing MNDPs; additionally, near-spherical organic fluorine MNDPs were in a position to build hot-water-repellent fabric, which preventing high-temperature droplets from infiltrating or spreading. Furthermore, mathematical analysis of the hot-water-repellent surface was carried out to establish its theoretical wetting model. We believe that the constructed MNDPs, equipped with controlled microstructure and chemical composition, are conducive to realizing the fine regulation of wettability for superwetting MNDPs-coated surface; by means of discussion for static and dynamic contact status of different temperature droplets onto anti-wetting-adjustable MNDPs-based surface, functional coated fabric, that exhibited superhydrophobicity or hot-water-repellency, would be formed, it has favourable research value on high durable non-wetted flexible textile coating; based on mathematical model of wetting state for hot-water-repellent surface, the mechanism, as regards effective blocking thermal-droplet at its contact area from wetting, is clearly clarified, which is beneficial to develop special industrial textiles with high-temperature water proofing.

Adaptation and Recovery of a Styrene-Acrylic Acid Copolymer Surface to Water.

Drops sliding down an adaptive surface lead to changes of the dynamic contact angles. Two adaptation processes play a role: 1) the adaptation of the surface upon bringing it into contact to the drop (wetting) and 2) the adaptation of the surface after the drop passed (dewetting). In order to study both processes, the authors investigate samples made from random styrene (PS)/acrylic acid (PAA) copolymers, which are exposed to water. Sum-frequency generation spectroscopy and tilted-plate measurements indicate that during wetting, the PS segments displace from the interface, while PAA segments are enriched. This structural adaptation of the PS/PAA random copolymer to water remains after dewetting. Annealing the adapted polymer induces reorientation of the PS segments to the surface.

Enhanced capillary zone electrophoresis in cyclic olefin copolymer microchannels using the combination of dynamic and static coatings for rapid analysis of carnosine and niacinamide in cosmetics

Cosmetics that have medicinal effects, including anti-inflammatory and antioxidant, have become a daily care routine consumption. The peptide additives, such as carnosine and nicotinamide, were frequently used to realize these medicinal effects. To accomplish rapid and effective quantitation of carnosine and niacinamide in cosmetics, capillary zone electrophoresis was executed in cyclic olefin copolymer microchips having both dynamic and static coatings. The static coating of cyclic olefin copolymer microchannel was constructed from bovine serum albumin adsorption, immobilization, and active site closure, while the dynamic coating was formed by adding surfactant into running buffer of capillary zone electrophoresis. The static coating can improve the hydrophilicity of cyclic olefin copolymer surface and avoid nonspecific peptide adsorption. The dynamic coating of sodium dodecyl sulfate in running buffer proved to be useful in flow velocity adjustment and the column efficiency enhancement in the capillary zone electrophoresis separation channel of the cyclic olefin copolymer microchip device. A separation resolution up to 4.24 on the mixture of carnosine and nicotinamide was obtained. Moreover, an analysis method was established and applied to simultaneous carnosine and nicotinamide determination in a liquid whitening essence and a solid antiglycation pill, and the results were verified by comparison with high-performance liquid chromatography methods, indicating its potential in complex sample analysis.

Quantifiable correlation of ToF‐SIMS and XPS data from polymer surfaces with controlled amino acid and peptide content

Peptide‐coated surfaces are widely employed in biomaterial design, but quantifiable correlation between surface composition and biological response is challenging due to, for example, instrumental limitations, a lack of suitable model surfaces or limitations in quantitatively correlating data from different surface analytical techniques. Here, we first establish a reference material that allows control over amino acid content. Reversible addition‐fragmentation chain‐transfer (RAFT) polymerisation is used to prepare a copolymer containing alkyne and furan units with well‐defined chain length and composition. Huisgen Cu(I)‐catalysed azide‐alkyne cycloaddition reaction is used to attach the model azido‐polyethyleneglycol‐amide‐modified pentafluoro‐l‐phenylalanine to the polymer. Different compositional ratios of the polymer provide a surface with varying amino acid content that is analysed by X‐ray photoelectron spectroscopy (XPS) and time‐of‐flight secondary ion mass spectrometry (ToF‐SIMS). Nitrogen‐related signals are compared with fluorine signals from both techniques. Fluorine and nitrogen signals from both techniques are found to be related to the copolymer compositions, but the homopolymer data deviate from this trend. The approach is then translated to a heparin‐binding peptide that supports cell adhesion. Human embryonic stem cells cultured on copolymer surfaces presenting different amounts of heparin‐binding peptide show strong cell growth while maintaining pluripotency after 72 h of culture. The early cell adhesion at 24 h can be correlated to the logarithm of the normalised CH4N+ ion intensity from ToF‐SIMS data, which is established as a suitable and generalisable marker ion for amino acids and peptides. This work contributes to the ability to use ToF‐SIMS in a more quantitative manner for the analysis of amino acid and peptide surfaces.

A low-fouling, self-assembled, graft co-polymer and covalent surface coating for controlled immobilization of biologically active moieties

Current biointerfaces aiming to steer specific biological responses frequently lack either stability due to purely electrostatic interactions, bioactivity due to unspecific conjugation chemistries, specificity due to uncontrolled biological interactions such as fouling, or cytocompatibility due to harsh and toxic coating procedures. Here, we report a versatile surface modification platform for covalent tethering of selected biomolecules. New in this approach is the particular combination of modular binding blocks as graft co-polymer. Grafted to the backbone of PAcrAmTM multiple functionalities are strategically combined: covalent (silane) and non-covalent (lysine) surface binding groups for stability and self-assembly in mild buffered solution, PEG-azide chains for low fouling properties, and specific, controlled, covalent, linking of biologically active molecules. This modular strategy overcomes the previously mentioned limitations, for instance regarding bioactivity of the biological moiety due to highly specific strain-promoted azide-alkyne cycloaddition. The successful grafting of the copolymer was confirmed by 1H NMR. The immobilization of RGD peptides was characterized by combining surface analytical techniques, such as ToF-SIMS and ellipsometry, allowing quantification of immobilized molecules over an extensive range of concentrations (0.008–1.95 pmol·cm−2). The bioactivity over this range of concentrations was confirmed by in vitro cell studies, presenting a differential endothelial cell attachment and spreading. The modified substrates enabled the formation of an interconnected monolayer of endothelial cells. Furthermore, the modular platform allowed the co-immobilization of two bioactive functional groups, RGD and biotin, on the same surface, which could be exploited for the further development of controlled multi-functional biointerfaces for diverse biological applications in the future.

Distinctive Adsorption Mechanism and Kinetics of Immunoglobulin G on a Nanoscale Polymer Surface.

Elucidation of protein adsorption beyond simple polymer surfaces to those presenting greater chemical complexity and nanoscopic features is critical to developing well-controlled nanobiomaterials and nanobiosensors. In this study, we repeatedly and faithfully track individual proteins on the same nanodomain areas of a block copolymer (BCP) surface and monitor the adsorption and assembly behavior of a model protein, immunoglobulin G (IgG), over time into a tight surface-packed structure. With discrete protein adsorption events unambiguously visualized at the biomolecular level, the detailed assembly and packing states of IgG on the BCP nanodomain surface are subsequently correlated to various regimes of IgG adsorption kinetic plots. Intriguing features, entirely different from those observed from macroscopic homopolymer templates, are identified from the IgG adsorption isotherms on the nanoscale, chemically varying BCP surface. They include the presence of two Langmuir-like adsorption segments and a nonmonotonic regime in the adsorption plot. Via correlation to time-corresponding topographic data, the unique isotherm features are explained with single biomolecule level details of the IgG adsorption pathway on the BCP. This work not only provides much needed, direct experimental evidence for time-resolved, single protein level, adsorption events on nanoscale polymer surfaces but also signifies mutual linking between specific topographic states of protein adsorption and assembly to particular segments of adsorption isotherms. From the fundamental research viewpoint, the correlative ability to examine the nanoscopic surface organizations of individual proteins and their local as well as global adsorption kinetic profiles will be highly valuable for accurately determining protein assembly mechanisms and interpreting protein adsorption kinetics on nanoscale surfaces. Application-wise, such knowledge will also be important for fundamentally guiding the design and development of biomaterials and biomedical devices that exploit nanoscale polymer architectures.

Multiple strategies to control the hydrophilic-hydrophobic balance of P(DMA-co-DMAEMA-co-QDMAEMA) coatings.

The regulation of the hydrophilic-hydrophobic balance of polymers has an important influence not only on their aggregation behavior in aqueous solution, but also on their adhesion properties on the surface of substrates and the applications of the modified surfaces. Based on this, a random copolymer poly(dopamine methacrylamide-co-2-(dimethylamino)ethyl methacrylate) (P(DMA-co-DMAEMA)) was synthesized as a starting polymer to generate P(DMA-co-DMAEMA-co-QDMAEMA) (PDDQ) derivatives by a programmable quaternization of the DMAEMA precursor. By adjusting the pH or temperature, both the aggregation behavior in aqueous solutions and the surface adhesive behavior on the substrate surfaces of PDDQ copolymers were regulated due to the hydrophilic-hydrophobic balance. Specifically, the surface adsorption of PDDQ copolymers on surfaces was enhanced by the increased hydrophobicity of PDDQ. Stainless steel meshes (SSM) modified with the PDDQ0 copolymer without quaternization showed a superoleophobicity in acidic aqueous media, which endowed it with improved oil-water separation performance. In addition, the hydrophilic-hydrophobic balance of PDDQs and their coatings could also be tuned by changing the ratio of DMAEMA to QDMAEMA in the copolymer. From PDDQ0 to PDDQ100, by increasing the hydrophilic QDMAEMA component of PDDQ copolymers, anti-protein properties and oil/water separation efficiency of the modified surfaces were also enhanced gradually. The results provided a reference for designing P(DMA-co-DMAEMA-co-QDMAEMA) coatings in different application environments.

Synthesis of An Amidoximated Acrylic Copolymer Membrane (AACM) Treated with Nano Silver Particles to Study the Antibacterial Efficiency of The Membrane

Polymers with cationic functional groups are proven to be an effective antimicrobial barrier. Particles, organic debris, and microbes can be well removed from drinking water using polymer membrane filtration. A variety of copolymers are utilized in the synthesis of such membranes. In this study, a copolymer membrane was synthesized first, and then Amidoximation was used to convert a portion of the copolymer’s nitrile groups to amidoxime groups. The membrane was treated with HA at 60-80°C in an aqueous solution to obtain an Amidoximated film. After being treated with Nano Silver particles, the efficiency of the prefabricated and particularly produced copolymer film as an antibacterial water disinfectant was analyzed. Various techniques were used to analyse the virgin and Amidoximated Acrylic Copolymer Membranes (AACM), including X-ray diffraction (EDX), Fourier Transform Infrared (FTIR), Scanning Electron Microscope, Transmission Electron Microscope, and Thermogravimetric analysis, Many substantial changes in the copolymer characteristics, including functionality, crystallinity, thermal activity, hydrophilicity, elemental composition, surface morphology, and antibacterial activity, were identified during the Amidoximation phase. It was revealed that an Amidoximated copolymer membrane outperforms an untreated membrane in terms of antibacterial activity.

Membranes for the Capture and Screening of Waterborne Plutonium Based on a Novel Pu-Extractive Copolymer Additive.

This contribution describes the fabrication of plutonium-adsorptive membranes by non-solvent induced phase separation. The dope solution comprised poly(vinylidene fluoride) (PVDF) and a Pu-extractive copolymer additive of PVDF-g-poly(ethylene glycol methacrylate phosphate) (EGMP) in dimethylformamide (DMF). The effects of casting conditions on membrane permeability were determined for PVDF membranes prepared with 10 wt% PVDF-g-EGMP. Direct-flow filtration and alpha spectrometry showed that membranes containing the graft copolymer could recover Pu up to 59.9 ± 3.0% from deionized water and 19.3 ± 3.5% from synthetic seawater after filtering 10 mL of 0.5 Bq/mL 238Pu. SEM-EDS analysis indicated that the graft copolymer was distributed evenly throughout the entire depth of the copolymer membranes, likely attributing to the tailing observed in the alpha spectra for 238Pu. Despite the reduction in resolution, the membranes exhibited high Pu uptake at the conditions tested, and new membrane designs that promote copolymer surface migration are expected to improve alpha spectrometry peak energy resolutions. Findings from this study also can be used to guide the development of extractive membranes for chromatographic separation of actinides from contaminated groundwater sources.