Polymers

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22 pages, 4232 KiB

Open AccessArticle

A Study of the Reinforcement Effect of MWCNTs onto Polyimide Flat Sheet Membranes

by Andreas A. Sapalidis, Panagiotis I. Karantzis, Achilles Vairis, Stephanos F. Nitodas, Stéphan Barbe and Evangelos P. Favvas

Polymers 2020, 12(6), 1381; https://doi.org/10.3390/polym12061381 - 19 Jun 2020

Cited by 7 | Viewed by 2310

Abstract

Polyimides rank among the most heat-resistant polymers and find application in a variety of fields, including transportation, electronics, and membrane technology. The aim of this work is to study the structural, thermal, mechanical, and gas permeation properties of polyimide based nanocomposite membranes in [...] Read more.

Polyimides rank among the most heat-resistant polymers and find application in a variety of fields, including transportation, electronics, and membrane technology. The aim of this work is to study the structural, thermal, mechanical, and gas permeation properties of polyimide based nanocomposite membranes in flat sheet configuration. For this purpose, numerous advanced techniques such as atomic force microscopy (AFM), SEM, TEM, TGA, FT-IR, tensile strength, elongation test, and gas permeability measurements were carried out. In particular, BTDA–TDI/MDI (Ρ84) co-polyimide was used as the matrix of the studied membranes, whereas multi-wall carbon nanotubes were employed as filler material at concentrations of up to 5 wt.% All studied films were prepared by the dry-cast process resulting in non-porous films of about 30–50 μm of thickness. An optimum filler concentration of 2 wt.% was estimated. At this concentration, both thermal and mechanical properties of the prepared membranes were improved, and the highest gas permeability values were also obtained. Finally, gas permeability experiments were carried out at 25, 50, and 100 °C with seven different pure gases. The results revealed that the uniform carbon nanotubes dispersion lead to enhanced gas permeation properties. Full article

(This article belongs to the Special Issue Polymers for Membrane Application)

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14 pages, 4228 KiB

Open AccessArticle

Reduction of Biofouling of a Microfiltration Membrane Using Amide Functionalities—Hydrophilization without Changes in Morphology

by Daniel Breite, Marco Went, Andrea Prager, Mathias Kühnert and Agnes Schulze

Polymers 2020, 12(6), 1379; https://doi.org/10.3390/polym12061379 - 19 Jun 2020

Cited by 6 | Viewed by 2367

Abstract

A major goal of membrane science is the improvement of the membrane performance and the reduction of fouling effects, which occur during most aqueous filtration applications. Increasing the surface hydrophilicity can improve the membrane performance (in case of aqueous media) and decelerates membrane [...] Read more.

A major goal of membrane science is the improvement of the membrane performance and the reduction of fouling effects, which occur during most aqueous filtration applications. Increasing the surface hydrophilicity can improve the membrane performance (in case of aqueous media) and decelerates membrane fouling. In this study, a PES microfiltration membrane (14,600 L m⁻² h⁻¹ bar⁻¹) was hydrophilized using a hydrophilic surface coating based on amide functionalities, converting the hydrophobic membrane surface (water contact angle, WCA: ~90°) into an extremely hydrophilic one (WCA: ~30°). The amide layer was created by first immobilizing piperazine to the membrane surface via electron beam irradiation. Subsequently, a reaction with 1,3,5-benzenetricarbonyl trichloride (TMC) was applied to generate an amide structure. The presented approach resulted in a hydrophilic membrane surface, while maintaining permeance of the membrane without pore blocking. All membranes were investigated regarding their permeance, porosity, average pore size, morphology (SEM), chemical composition (XPS), and wettability. Soxhlet extraction was carried out to demonstrate the stability of the applied coating. The improvement of the modified membranes was demonstrated using dead-end filtration of algae solutions. After three fouling cycles, about 60% of the initial permeance remain for the modified membranes, while only ~25% remain for the reference. Full article

(This article belongs to the Special Issue Polymers for Membrane Application)

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19 pages, 6211 KiB

Open AccessArticle

Obtainment and Characterization of Hydrophilic Polysulfone Membranes by N-Vinylimidazole Grafting Induced by Gamma Irradiation

by Elizabeth Vázquez, Claudia Muro, Javier Illescas, Guillermina Burillo, Omar Hernández and Ernesto Rivera

Polymers 2020, 12(6), 1284; https://doi.org/10.3390/polym12061284 - 04 Jun 2020

Cited by 6 | Viewed by 2700

Abstract

Polysulfone (PSU) film and N-vinylimidazole (VIM) were used to obtain grafted membranes with high hydrophilic capacity. The grafting process was performed by gamma irradiation under two experiments: (1) different irradiation doses (100–400 kGy) and VIM 50% solution; (2) different concentration of grafted VIM [...] Read more.

Polysulfone (PSU) film and N-vinylimidazole (VIM) were used to obtain grafted membranes with high hydrophilic capacity. The grafting process was performed by gamma irradiation under two experiments: (1) different irradiation doses (100–400 kGy) and VIM 50% solution; (2) different concentration of grafted VIM (30–70%) and 300 kGy of irradiation dose. Characteristics of the grafted membranes were determined by Fourier transform infrared spectroscopy (FTIR), scanning electron microscopy (SEM), contact angle, swelling degree, desalination test, thermogravimetric analysis (TGA) and differential scanning calorimetry (DSC). Both experiments indicated that the absorbed dose 300 kGy and the VIM concentration, at 50% v/v, were effective to obtain PSU grafted membranes with 14.3% of grafting yield. Nevertheless, experimental conditions, 400 kGy, VIM 50% and 300 kGy, VIM 60–70% promoted possible membrane degradation and VIM homopolymerization on the membrane surface, which was observed by SEM images; meanwhile, 100–200 kGy and VIM 30–50% produced minimal grafting (2 ± 0.5%). Hydrophilic surface of the grafted PSU membranes by 300 kGy and VIM 50% v/v were corroborated by the water contact angle, swelling degree and desalination test, showing a decrease from 90.7° ± 0.3 (PSU film) to 64.3° ± 0.5; an increment of swelling degree of 25 ± 1%, and a rejection-permeation capacity of 75 ± 2%. In addition, the thermal behavior of grafted PSU membranes registered an increment in the degradation of 20%, due to the presence of VIM. However, the normal temperature of the membrane operation did not affect this result; meanwhile, the glass transition temperature (T_g) of the grafted PSU membrane was found at 185.4 ± 0.5 °C, which indicated an increment of 15 ± 1%. Full article

(This article belongs to the Special Issue Polymers for Membrane Application)

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14 pages, 2109 KiB

Open AccessArticle

Synthesis and Gas Transport Properties of Addition Polynorbornene with Perfluorophenyl Side Groups

by Gleb O. Karpov, Ilya L. Borisov, Alexey V. Volkov, Eugene Sh. Finkelshtein and Maxim V. Bermeshev

Polymers 2020, 12(6), 1282; https://doi.org/10.3390/polym12061282 - 03 Jun 2020

Cited by 11 | Viewed by 3160

Abstract

Polynorbornenes represent a fruitful class of polymers for structure–property study. Recently, vinyl-addition polynorbornenes bearing side groups of different natures were observed to exhibit excellent gas permeation ability, along with attractive C₄H₁₀/CH₄ and CO₂/N₂ separation selectivities. [...] Read more.

Polynorbornenes represent a fruitful class of polymers for structure–property study. Recently, vinyl-addition polynorbornenes bearing side groups of different natures were observed to exhibit excellent gas permeation ability, along with attractive C₄H₁₀/CH₄ and CO₂/N₂ separation selectivities. However, to date, the gas transport properties of fluorinated addition polynorbornenes have not been reported. Herein, we synthesized addition polynorbornene with fluoroorganic substituents and executed a study on the gas transport properties of the polymer for the first time. A norbornene-type monomer with a C₆F₅ group, 3-pentafluorophenyl-exo-tricyclononene-7, was successfully involved in addition polymerization, resulting in soluble, high-molecular-weight products obtained in good or high yields. By varying the monomer concentration and monomer/catalyst ratio, it was possible to reach M_w values of (2.93–4.35) × 10⁵. The molecular structure was confirmed by NMR and FTIR analysis. The contact angle with distilled water revealed the hydrophobic nature of the synthesized polymer as expected due to the presence of fluoroorganic side groups. A study of the permeability of various gases (He, H₂, O₂, N₂, CO₂, and CH₄) through the prepared polymer disclosed a synergetic effect, which was achieved by the presence of both bulky perfluorinated side groups and rigid saturated main chains. Addition poly(3-pentafluorophenyl-exo-tricyclononene-7) was more permeable than its metathesis analogue by a factor of 7–21, or the similar polymer with flexible main chains, poly(pentafluorostyrene), in relation to the gases tested. Therefore, this investigation opens the door to fluorinated addition polynorbornenes as new potential polymeric materials for membrane gas separation. Full article

(This article belongs to the Special Issue Polymers for Membrane Application)

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10 pages, 8291 KiB

Open AccessArticle

Lignin Nanoparticle-Coated Celgard Separator for High-Performance Lithium–Sulfur Batteries

by Zengyao Zhang, Shun Yi, Yuejia Wei, Huiyang Bian, Ruibin Wang and Yonggang Min

Polymers 2019, 11(12), 1946; https://doi.org/10.3390/polym11121946 - 27 Nov 2019

Cited by 23 | Viewed by 4251

Abstract

Tremendous efforts have been made toward the development of lithium–sulfur (Li–S) batteries as one of the most reasonable solutions to the rapidly increasing demand for portable electronic devices and electric vehicles, owing to their high cost-efficiency and theoretical energy density. However, the shuttle [...] Read more.

Tremendous efforts have been made toward the development of lithium–sulfur (Li–S) batteries as one of the most reasonable solutions to the rapidly increasing demand for portable electronic devices and electric vehicles, owing to their high cost-efficiency and theoretical energy density. However, the shuttle effect caused by soluble polysulfides is generally considered to be an insurmountable challenge, which can significantly reduce the battery lifecycle and sulfur utilization. Here, we report a lignin nanoparticle-coated Celgard (LC) separator to alleviate this problem. The LC separator enables abundant electron-donating groups and is expected to induce chemical binding of polysulfides to hinder the shuttle effect. When a sulfur-containing commercially available acetylene black (approximately 73.8 wt% sulfur content) was used as the cathode without modification, the Li–S battery with the LC separator presented much enhanced cycling stability over that with the Celgard separator for over 500 cycles at a current density of 1 C. The strategy demonstrated in this study is expected to provide more possibilities for the utilization of low-cost biomass-derived nanomaterials as separators for high-performance Li–S batteries. Full article

(This article belongs to the Special Issue Polymers for Membrane Application)

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17 pages, 3626 KiB

Open AccessArticle

A Combination of Aqueous Extraction and Polymeric Membranes as a Sustainable Process for the Recovery of Polyphenols from Olive Mill Solid Wastes

by Carmela Conidi, Agata Egea-Corbacho and Alfredo Cassano

Polymers 2019, 11(11), 1868; https://doi.org/10.3390/polym11111868 - 12 Nov 2019

Cited by 11 | Viewed by 2329

Abstract

Polyamide commercial membranes in flat-sheet configuration and with molecular weight cut-off (MWCO) in the range of ultrafiltration (UF) to nanofiltration (NF) were tested for the recovery of phenolic compounds from clarified olive mill solid waste (OMSW) aqueous extracts. The performance of selected membranes [...] Read more.

Polyamide commercial membranes in flat-sheet configuration and with molecular weight cut-off (MWCO) in the range of ultrafiltration (UF) to nanofiltration (NF) were tested for the recovery of phenolic compounds from clarified olive mill solid waste (OMSW) aqueous extracts. The performance of selected membranes was evaluated in terms of productivity (permeate flux) and selectivity towards biologically active compounds (such as phenolic compounds, flavanols, and hydroxycinnamic acids derivatives) and total antioxidant activity (TAA) as a function of transmembrane pressure (TMP). NF membranes produced higher permeate fluxes and a lower fouling index in comparison with UF membranes. Retention of bioactive compounds was also significantly higher for NF membranes than for UF membranes. In particular, membranes with MWCO in the range 150–500 Da showed rejection towards flavanols and hydroxycinnamic acid derivatives of about 100%. On the other hand, the rejection towards TAA and total polyphenols was of about 90% and 72%, respectively. Therefore, NF retentate fractions appear of practical interest for the production of food additives and food supplements due to their high antioxidant activity. Full article

(This article belongs to the Special Issue Polymers for Membrane Application)

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11 pages, 2139 KiB

Open AccessArticle

Novel Solid-State Potentiometric Sensors Using Polyaniline (PANI) as A Solid-Contact Transducer for Flucarbazone Herbicide Assessment

by Ayman H. Kamel, Abd El-Galil E. Amr, Nashwa S. Abdalla, Mohamed El-Naggar, Mohamed A. Al-Omar, Hamad M. Alkahtani and Ahmed Y. A. Sayed

Polymers 2019, 11(11), 1796; https://doi.org/10.3390/polym11111796 - 01 Nov 2019

Cited by 21 | Viewed by 2689

Abstract

Novel potentiometric solid-contact ion-selective electrodes (SC/ISEs) based on molecularly imprinted polymers (MIPs) as sensory carriers (MIP/PANI/ISE) were prepared and characterized as potentiometric sensors for flucarbazone herbicide anion. However, aliquat S 336 was also studied as a charged carrier in the fabrication of Aliquat/PANI/ISEs [...] Read more.

Novel potentiometric solid-contact ion-selective electrodes (SC/ISEs) based on molecularly imprinted polymers (MIPs) as sensory carriers (MIP/PANI/ISE) were prepared and characterized as potentiometric sensors for flucarbazone herbicide anion. However, aliquat S 336 was also studied as a charged carrier in the fabrication of Aliquat/PANI/ISEs for flucarbazone monitoring. The polyaniline (PANI) film was inserted between the ion-sensing membrane (ISM) and the electronic conductor glassy carbon substrate (GC). The sensors showed a noticeable response towards flucarbazone anions with slopes of −45.5 ± 1.3 (r² = 0.9998) and −56.3 ± 1.5 (r² = 0.9977) mV/decade over the range of 10⁻²–10⁻⁵, 10⁻²–10⁻⁴ M and detection limits of 5.8 × 10⁻⁶ and 8.5 × 10⁻⁶ M for MIP/PANI/ISE and Aliguat/PANI/ISE, respectively. The selectivity and long-term potential stability of all presented ISEs were investigated. The short-term potential and electrode capacitances were studied and evaluated using chronopotentiometry and electrochemical impedance spectrometry (EIS). The proposed ISEs were introduced for the direct measurement of flucarbazone herbicide in different soil samples sprayed with flucarbazone herbicide. The results agree well with the results obtained using the standard liquid chromatographic method (HPLC). Full article

(This article belongs to the Special Issue Polymers for Membrane Application)

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11 pages, 4383 KiB

Open AccessArticle

Construction of Antifouling Membrane Surfaces through Layer-by-Layer Self-Assembly of Lignosulfonate and Polyethyleneimine

by Lin Gu, Meng-Yun Xie, Yu Jin, Min He, Xiao-Yan Xing, Yuan Yu and Qing-Yun Wu

Polymers 2019, 11(11), 1782; https://doi.org/10.3390/polym11111782 - 31 Oct 2019

Cited by 37 | Viewed by 5020

Abstract

Lignin is the second most abundant and low-cost natural polymer, but its high value-added utilization is still lack of effective and economic ways. In this paper, waste lignosulfonate (LS) was introduced to fabricate antifouling membrane surfaces via layer-by-layer self-assembly with polyethyleneimine (PEI). The [...] Read more.

Lignin is the second most abundant and low-cost natural polymer, but its high value-added utilization is still lack of effective and economic ways. In this paper, waste lignosulfonate (LS) was introduced to fabricate antifouling membrane surfaces via layer-by-layer self-assembly with polyethyleneimine (PEI). The LS/PEI multilayers were successfully deposited on the polysulfone (PSf) membrane, as demonstrated by ATR-FTIR, XPS, Zeta potential measurements, AFM, and SEM. Meanwhile, the effect of the number of bilayers was investigated in detail on the composition, morphologies, hydrophilicity, and antifouling performance of the membrane surface. As a result, with the bilayer numbers increase to 5, the PSf membrane shows smooth surface with small roughness, and its water contact angle reduces to 44.1°, indicating the improved hydrophilicity. Accordingly, the modified PSf membrane with 5 LS/PEI bilayers repels the adsorption of protein, resulting in good antifouling performance. This work provides a green, facile, and low-cost strategy to construct antifouling membrane surfaces. Full article

(This article belongs to the Special Issue Polymers for Membrane Application)

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13 pages, 1885 KiB

Open AccessArticle

Potentiometric PVC-Membrane-Based Sensor for Dimethylamine Assessment Using A Molecularly Imprinted Polymer as A Sensory Recognition Element

by Saad S. M. Hassan, Abd El-Galil E. Amr, Heba Abd El-Naby, Mohamed A. Al-Omar, Ayman H. Kamel and Nagy M. Khalifa

Polymers 2019, 11(10), 1695; https://doi.org/10.3390/polym11101695 - 16 Oct 2019

Cited by 9 | Viewed by 2278

Abstract

A new simple potentiometric sensor is developed and presented for sensitive and selective monitoring of dimethylamine (DMA). The sensor incorporates a molecularly imprinted polymer, with a pre-defined specific cavity suitable to accommodate DMA. The molecularly imprinted polymer (MIP) particles were dispersed in an [...] Read more.

A new simple potentiometric sensor is developed and presented for sensitive and selective monitoring of dimethylamine (DMA). The sensor incorporates a molecularly imprinted polymer, with a pre-defined specific cavity suitable to accommodate DMA. The molecularly imprinted polymer (MIP) particles were dispersed in an aplasticized poly(vinyl chloride) matrix. The MIP is synthesized by using a template molecule (DMA), a functional monomer (acrylamide, AM), cross-linker (ethylene glycol dimethacrylate, EGDMA) and initiating reagent (benzoylperoxide, BPO). Using Trizma buffer solution (5 mmol L⁻¹, pH 7.1), the sensor exhibits a rapid, stable and linear response for 1.0 × 10⁻⁵ to 1.0 × 10⁻² mol L⁻¹ DMA⁺ with a calibration slope of 51.3 ± 0.3 mV decade⁻¹, and a detection limit of 4.6 × 10⁻⁶ mol L⁻¹ (0.37 µg mL⁻¹). The electrode exhibited a short response time (10 s) and stable potential readings (± 0.5 mV) for more than 2 months. Potentiometric selectivity measurements of the sensor reveal negligible interferences from most common aliphatic and aromatic amines. High concentration levels (100-fold excess) of many inorganic cations do not interfere. The sensor is successfully used for quantification of low levels of DMA down to 0.5 µg mL^–1. Verification of the presented method was carried out after measuring the detection limit, working linearity range, ruggedness of the method, accuracy, precision, repeatability and reproducibility. Under flow-through conditions, the proposed sensor in its tubular form is prepared and introduced in a two-channel flow injection setup for hydrodynamic determination of DMA. The sampling rate is 50–55 samples h^–1. The sensor is used to determine DMA in different soil samples with an accuracy range of 97.0–102.8%. Full article

(This article belongs to the Special Issue Polymers for Membrane Application)

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11 pages, 1948 KiB

Open AccessArticle

Tailor-Made Specific Recognition of Cyromazine Pesticide Integrated in a Potentiometric Strip Cell for Environmental and Food Analysis

by Nashwa S. Abdalla, Abd El-Galil E. Amr, Aliaa S. M. El-Tantawy, Mohamed A. Al-Omar, Ayman H. Kamel and Nagy M. Khalifa

Polymers 2019, 11(9), 1526; https://doi.org/10.3390/polym11091526 - 19 Sep 2019

Cited by 17 | Viewed by 2972

Abstract

Screen-printed ion-selective electrodes were designed and characterized for the assessment of cyromazine (CYR) pesticide. A novel approach is to design tailor-made specific recognition sites in polymeric membranes using molecularly imprinted polymers for cyromazine (CR) determination (sensor I). Another sensor (sensor II) is the [...] Read more.

Screen-printed ion-selective electrodes were designed and characterized for the assessment of cyromazine (CYR) pesticide. A novel approach is to design tailor-made specific recognition sites in polymeric membranes using molecularly imprinted polymers for cyromazine (CR) determination (sensor I). Another sensor (sensor II) is the plasticized PVC membrane incorporating cyromazine/tetraphenyl borate ion association complex. The charge-transfer resistance and water layer reached its minimal by incorporating Polyaniline (PANI) solid-contact ISE. The designed electrodes demonstrated Nernstain response over a linear range 1.0 × 10⁻²–5.2 × 10⁻⁶ and 1.0 × 10⁻²–5.7 × 10⁻⁵ M with a detection limit 2.2 × 10⁻⁶ and 8.1 × 10⁻⁶ M for sensors I and II, respectively. The obtained slopes were 28.1 ± 2.1 (r² = 0.9999) and 36.4 ± 1.6 (r² = 0.9991) mV/decade, respectively. The results showed that the proposed electrodes have a fast and stable response, good reproducibility, and applicability for direct measurement of CYR content in commercial pesticide preparations and soil samples sprayed with CYR pesticide. The results obtained from the proposed method are fairly in accordance with those using the standard official method. Full article

(This article belongs to the Special Issue Polymers for Membrane Application)

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21 pages, 2162 KiB

Open AccessArticle

Thermal Cross Linking of Novel Azide Modified Polymers of Intrinsic Microporosity—Effect of Distribution and the Gas Separation Performance

by Silvio Neumann, Gisela Bengtson, David Meis and Volkan Filiz

Polymers 2019, 11(8), 1241; https://doi.org/10.3390/polym11081241 - 26 Jul 2019

Cited by 14 | Viewed by 5101

Abstract

The synthesis of polymers of intrinsic microporosity (PIM) modified with azide groups, the cross linkage by nitrene reaction and their performance as gas separation membranes are reported. The azide modification of the spirobisindane units in the polymer backbone was done by post functionalization [...] Read more.

The synthesis of polymers of intrinsic microporosity (PIM) modified with azide groups, the cross linkage by nitrene reaction and their performance as gas separation membranes are reported. The azide modification of the spirobisindane units in the polymer backbone was done by post functionalization of methylated spirobisindane containing polymers. These polymers differ in distribution and concentration of the azide group containing spirobisindane units by applying perfectly alternating and randomly distributed copolymers along the polymer chains. To investigate the influence of concentration of the azide groups, additionally the homopolymer of methylated spirobisindane was synthesized and subjected to identical treatments and characterizations as both copolymers. Cross linkage by nitrene reaction was examined by different temperature treatments at 150, 200, 250 and 300 °C. Characterization of the new polymers was performed by NMR, SEC and FT-IR. Furthermore, the crosslinking process was investigated by means of solid state NMR, TGA-FTIR, DSC and isoconversional kinetic analysis performed with TGA. Gas permeability of CO₂, N₂, CH₄, H₂ and O₂ was determined by time lag experiments and ideal selectivities for several gas pairs were calculated. The two azide groups per repeating unit degrade during thermal treatments by release of nitrogen and form mechanically stable PIM networks, leading to an increase in gas permeability while selectivity remained nearly constant. Measured diffusivity and solubility coefficients revealed differences in the formation of free volume elements depending on distribution and concentration of the azide groups. Aging studies over about five months were performed and physical aging rates (β_P) were evaluated with regard to the concentration and distribution of curable azide functionalities. Subsequently, the enhanced sieving effect during aging resulted in membrane materials that surpassed the Robeson upper bound in selected gas pairs. Full article

(This article belongs to the Special Issue Polymers for Membrane Application)

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12 pages, 2486 KiB

Open AccessArticle

Non-Equilibrium Potential Responses towards Neutral Orcinol Using All-Solid-State Potentiometric Sensors Integrated with Molecularly Imprinted Polymers

by Saad S. M. Hassan, Abd El-Galil E. Amr, Nada H. A. Elbehery, Mohamed A. Al-Omar and Ayman H. Kamel

Polymers 2019, 11(8), 1232; https://doi.org/10.3390/polym11081232 - 25 Jul 2019

Cited by 9 | Viewed by 2687

Abstract

Molecularly imprinted polymer (MIP) receptors have been synthesized, characterized, and applied as new selective receptors in solid-contact ion selective electrodes (ISEs) towards non-dissociated 3,5-dihydroxytoluene (orcinol). Two monomers, namely methacrylic acid (MAA) and acrylamide (AA), were used in the preparation of MIP receptors. Graphene [...] Read more.

Molecularly imprinted polymer (MIP) receptors have been synthesized, characterized, and applied as new selective receptors in solid-contact ion selective electrodes (ISEs) towards non-dissociated 3,5-dihydroxytoluene (orcinol). Two monomers, namely methacrylic acid (MAA) and acrylamide (AA), were used in the preparation of MIP receptors. Graphene (Gr) was used as the solid contact material between the sensing membrane and the electrical contact substrate. Based on non-equilibrium sensing mechanism, the proposed sensors reveal observably enhanced detection sensitivity towards orcinol with detection limits 1.7 × 10⁻⁵ and 3.3 × 10⁻⁶ M for sensors based on MIP/MAA and MIP/AA, respectively. The selectivity coefficients measured by the modified separate solution method (MSSM) for the proposed sensors showed good selectivity towards orcinol over most common other phenols and inorganic anions. All measurements were made in the presence of 30 mM phosphate buffer solution (PBS) with a pH of 7.0. Potential stability for the proposed sensors was tested by constant-current chronopotentiometry. No water films were formed between the sensing membrane and the electron conductor substrate. The applicability of MIP/MAA incorporated ISE has been checked by recovery test of orcinol in the presence of soil matrix and by standard addition method. Full article

(This article belongs to the Special Issue Polymers for Membrane Application)

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