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Separation of hydrogen isotopes is an important process in materials science, biomedical research, and nuclear fields. In this study, we used a polymer electrolyte fuel cell to separate protium (H) and deuterium (D). Here a circulation system recycled hydrogen gas at the anode was used. H and D were enriched in the gas and water phases, respectively. The separation efficiency depends on the gas flow rate through the parameter λ, which describes the stoichiometric ratio of circulation gas to feed gas. H and D were simultaneously enriched in their respective phases. The circulation system prolonged the gas circulation time in the system to improve the separation efficiency. • Polymer electrolyte fuel cell was applied for deuterium separation. • Anode gas circulation promoted the protium enrichment in the fuel gas. • Gas flow and consumption rate was discussed for the optimal separation. [ABSTRACT FROM AUTHOR]

High value-added reuse of waste vehicle polymers can effectively alleviate the global resource shortage and environmental degradation. How to separate mixed polymers cleanly and efficiently is an important prerequisite for their reuse. In the paper, polyamide (PA)/ polypropylene (PP)/acrylonitrile-butadiene-styrene (ABS) and polyethylene (PE)/PP/polyvinylchloride (PVC) of vehicle polymer mixed particles are taken as the research objects, and the tribo-electrostatic separation of three-component mixed particles is studied using the designed double-stage device for tribo-aero-electrostatic separation. First, the optimal installation angle of the fluidized bed reflow plate is determined to be 45° by using the coupling method of computational fluid dynamics and discrete element. Second, the gas velocity for forming a fast bed and the optimal charging time for two sets of mixed particles are identified by tribo-charging experiments. The separation voltage for the two sets of mixed particles is also determined using COMSOL software. Furthermore, based on the determined parameters, two sets of tribo-electrostatic separation experiments are carried out. Results showed that the purities of PA and ABS particles are more than 91%, the purities of the PE, PP (white), and PVC particles are more than 85%. The research provides a reference for the two-stage tribo-electrostatic separation of vehicle polymer mixed particles. [ABSTRACT FROM AUTHOR]

• MOPs and their breakthroughs in membrane application are systematically summarized. • The development, synthetic means and structural design of MOPs is presented. • The challenges in preparing precise molecular sieving MOPs membrane are discussed. Microporous organic polymers (MOPs) are ideal candidates for designing highly efficient and precise molecular sieving separation membranes due to their exceptional porosity, rigid pore structure, pore size designability, and ease of functionalization. These materials encompass COFs, POCs, PAFs, PIMs, CMPs, and HCPs. However, the path to utilizing MOPs as separation membrane applications has encountered obstacles. Several studies have been conducted to fully exploit the exceptional properties of these polymers. The better application of MOPs materials should be considered in terms of material design and synthesis, membrane formation, and membrane task-specific applications. This review objectively reclassifies MOPs materials based on the latest research and material ordering and provides a systematic summary of MOPs material synthesis and design, MOPs-based membrane fabrication difficulties, and current novel MOPs-based membrane design. Additionally, it introduces in detail the preparation of different types of MOPs-based membranes. The applications of MOPs-based membranes in separation applications are also thoroughly summarized. Finally, this review summarizes the challenges of current MOPs-based membrane development, proposes future opportunities and potential applications in the separation and purification field. [ABSTRACT FROM AUTHOR]

Organogels that lock organic solvents within a polymer network shows promising applications in ice-phobicity, anti-biofouling, conserving cultural heritage etc. However, the synthesis of organogels by versatile and cost-effective methods still remain challenging. Here, we introduce a novel and economical approach to organogel preparation via crystallization-induced polymer precipitation, which involves the straightforward blending of carbonyl contained polymer, nano Ca(OH) 2 , and excess ethyl acetate (EA). During the formation, nano Ca(OH) 2 reacts with EA to produce ethanol and calcium acetate, in which Ca2+ ionically bonds with carbonyl of polymer. Due to the low solubility in EA and ethanol, calcium acetate initiates crystallization. The interaction between Ca(CH 3 COO) 2 and polymer induces the separation of polymer from the solvent, thereby forming a network that locks the surplus EA and ethanol. More importantly, the organogel is capable not only of encapsulating 12 organic solvents within its precursor but also of effectively removing various aged polymeric coatings from wall paintings without leaving residues. This innovative organogel system marks a significant forward in the realm of organogel with applications in conservation and surface engineering. [Display omitted] • A novel organogel is synthesized by crystallization-induced polymer network method. • It is prepared by mixing carbonyl contained polymer, nano Ca(OH) 2 , and ethyl acetate. • It can effectively remove aged polymers coated on the surface of wall painting. [ABSTRACT FROM AUTHOR]

A 1D chain coordination polymer with 1D channels along the c axis has been synthesized. Benefiting from the use of ionic-type ligands, the complex has a uniform distribution of positive N+ sites and negative carboxylate groups, which produced an electrical field gradient. The complex exhibits different adsorption behaviors for C 2 -C 3 alkyne/alkene and efficient separation of mixtures. [Display omitted] • By utilizing an ionic-type ligand (3,5-dicarboxy-1-ethylpyridin-1-ium bromide), a novel coordination polymer with intrinsic charged sites has been successfully constructed. • The 1D chains of the complex interact with others through non-conventional charge-assisted C H···O hydrogen bonds. • The complex exhibits separation selectivities for C 2 -C 3 alkyne/alkene mixtures. C 2 –C 3 alkyne/alkene adsorption and separation is a critical process in industrial production, but it remains challenging due to the similar size of gas molecules. Herein, based on an ionic-type ligand, a porous coordination polymer with inherent positive charged sites has been successfully constructed by 1D chains through non-conventional C H···O hydrogen bonds. The flexible framework shows adsorption ability for C 2 H 2 while negligible adsorption of C 2 H 4 ; and a much earlier steep increase for C 3 H 4 isotherm compared to C 3 H 6 isotherm in the low-pressure region. Ideal adsorbed solution theory further illustrated that the framework has the ability to separate C 2 H 2 /C 2 H 4 and C 3 H 4 /C 3 H 6 mixtures. [ABSTRACT FROM AUTHOR]

It has been widely studied the impact of polar side-chain on the modification of conjugated polymers and the thermoelectric properties of composites, but relatively little research has been carried out in the gas sensing field. In this study, two π-conjugated polymers PFTC8 and PFTO with similar backbone but different polar-side chains were synthesized. The separation efficiency of the polymers for semiconducting single-walled (sc-SWCNTs) and the NO 2 sensing performance were also investigated. It was found that the introduction of the polar side chains not only enhanced the sorting efficiency of the polymer for sc-SWCNTs (greater than 99 %), but also further improved the responsive performance of the sensor to NO 2. After the introduction of polar side chains, the response value of the composite PFTO@sc-SWCNTs towards 1 ppm NO 2 was achieved to be 21.7 % at room temperature. Furthermore, the response time (T res = 23 s) and recovery time (T rec = 134 s) of PFTO@sc-SWCNTs to 1 ppm NO 2 were also greatly shortened. The strategy for improving the NO 2 gas response performance by introducing polar side chains is proposed. [Display omitted] • The capacity of wrapping sc-SWCNTs was increased by polar tri-glycol side chains. • The PFTO@sc-SWCNTs showed a response value of 21.7 % towards NO 2 at 1 ppm. • The response time to NO 2 was shortened by the polar tri-glycol side chain(23 s/1 ppm). [ABSTRACT FROM AUTHOR]

While numerous studies have explored the potential of shape memory materials in medical applications, the current research output is not enough for significant productivity in industrial products. In this research, a type of shape memory orthopedic plaster was fabricated by using epoxy/polyurethane interpenetrating networks modified with epoxidized soybean oil (ESO) and then compared with some commercial plasters. Polymer networks that were produced could be tailored to have glass transition temperatures (Tgs) within the range of 70–90 °C by changing the percentage composition of polyurethane and soybean oil. Shape recovery and fixity ratios in all samples were above 95 and 97 %. DMA results showed that IPNs with variable amount of soybean oil had lower glass transition temperature (Tg) and cross-link densities compared to IPNs without soybean oil. Based on the tensile test results, most samples exhibited an elastic modulus in the range of 280–400MPa, a level deemed somewhat acceptable when compared to commercial samples. Light microscope images had shown that the increase of polyurethane led to the phase separation of polymers, which was improved by the addition of soybean oil. [Display omitted] • Shape memory EP/PU IPNs were fabricated by solution blending method and then modified with soybean oil. • The T g of the IPNs was controlled by changing the EP/PU ratio as well as soybean oil content. • The phase separation between epoxy and polyurethane was controlled by the addition of soybean oil. • Fabricated IPNs may be appropriate for new generation of plasters due to their high toughness and shape memory properties. [ABSTRACT FROM AUTHOR]

Polymer-supported MOFs membranes with high separation performances show great potentials in industrial purification of H 2. The key to growing defect-free and adherent MOFs layers on polymer substrates is the abundant and uniformly distributed nucleation sites on the surface of polymer substrates. Therefore, in this work, a mixed-matrix polyacrylonitrile (PAN) substrate with ZIF-8-rich seed layer (ZS-PAN) was constructed by gravity induced deposition and gradient distribution of ZIF-8 before phase inversion, then under the assistance of Tannic acid (TA), the dense and defect-free ZIF-8 membrane on flexible polymer substrate was fabricated followed by the secondary growth of ZIF-8. The EDS and SEM results of the membrane cross-section confirm the gradient distribution of ZIF-8 seeds, and the resultant membranes are defect-free. The H 2 permeance of TA-ZIF-8/ZS-PAN membrane is 953.66 GPU, and the H 2 /CO 2 selectivity is 12.09, which is 80.17 % higher than that of ZIF-8/ZS-PAN membrane without TA, exceeding the Robeson upper bound in 2008. This improved H 2 separation performance is derived from the following reasons. First, gravity-induced ZIF-8 seed deposition constructs a ZIF-8-rich seed layer on the mixed-matrix polymer substrate, which increases the nucleation sites. Second, the introduction of TA during the secondary growth process further increases the nucleation sites by hydroxyl-chelated zinc ions, both of which contribute to the dense ZIF-8 membrane. At the same time, the hydroxyl group in TA is CO 2 -philic, which can delay CO 2 permeation and improve the H 2 /CO 2 separation performance by physically adsorbing CO 2. The proposed mixed-matrix substrate by gravity induced deposition of MOFs provides a novel strategy for constructing defect-free and flexible MOFs membrane. [Display omitted] • External gravity field is utilized to induce ZIF-8 deposition. • Mixed-matrix polymer substrate is constructed with ZIF-8-rich seeds layer. • TA was used to assist ZIF-8 growth by hydroxyl-chelated zinc ions. • The TA-ZIF-8/ZS-PAN membrane is defect-free with improved H 2 separation. [ABSTRACT FROM AUTHOR]

Mixed matrix membranes (MMMs) having ionic liquid (IL) modified metal-organic frameworks (MOF) as fillers present a broad potential for enhancing the separation properties of the polymers. Here, we incorporated an IL, 1-butyl-1-methyl-pyrrolidinium tricyanomethanide [BMPyr][TCM], into MOF-177 and used the corresponding composite as filler in Pebax polymer to fabricate IL/MOF-177/Pebax MMMs at different filler loadings. These MMMs along with those prepared by using pristine MOF-177 as a filler were then tested for CO 2 /N 2 separation by measuring their CO 2 and N 2 permeabilities at 35 °C and 1 bar. The [BMPyr][TCM]/MOF-177/Pebax MMM having 10 wt.% filler loading showed remarkable improvements in both CO 2 permeability (137 ± 2.0 Barrer) and CO 2 /N 2 selectivity (622 ± 105) compared to the neat Pebax membrane having corresponding performance values of 98.0 ± 2.0 Barrer and 64.5 ± 6.0, respectively. This simultaneous improvement in both CO 2 permeability and CO 2 /N 2 selectivity breaks the trade-off limitation of polymer membranes. Besides, the MMMs having 10 and 15 wt.% loadings of fillers were located well above the updated Robeson's upper bound, demonstrating the great promise of [BMPyr][TCM]/MOF-177/Pebax MMMs for CO 2 /N 2 separation. [Display omitted] • [BMPyr][TCM] was incorporated into MOF-177 to synthesize IL/MOF composite. • IL/MOF-177 composite used as a filler in Pebax to synthesize IL/MOF-177/Pebax MMMs. • MMM with 10 wt% filler breaks trade-off limitation. • It also outperforms the Robeson's upper bound. [ABSTRACT FROM AUTHOR]

Environmental and human health are adversely affected by oil and organic wastewater pollution of water resources. However, it has always been difficult to develop an adsorption material that is multifunctional and able to remove multiple pollutants. A new hierarchically porous polymers have been synthesized using high internal phase emulsions (HIPE) template, and further modification by a physico-chemical synergy method of epoxidized soybean oil (ESO) coupled with stearic acid (STA). The modified polyHIPE (E/S-polyHIPE) exhibit superhydrophobic properties with water contact angle as high as 161.12°, and exhibit excellent robustness and chemical resistance. Oil/water mixtures can be separated using E/S-polyHIPE with a high separation efficiency (99.00–99.42 %), and it has a high oil absorption capacity (16–28 g/g) for a wide range of oil types. After 15 separation cycles, the E/S-polyHIPE exhibits excellent separation efficiency (＞ 97 %) because of its promising mechanical durability. E/S-polyHIPE still performed outstanding oil absorption capacity for floating oil, underwater oil, and emulsified oil, also it can be used as a continuous in-situ oil-water separator. An innovative approach to the fabrication of a sustainable multifunctional absorbent for oily wastewater is presented in this work, which illustrates the great potential for large-scale practical application. [Display omitted] • A highly efficient oil-water separation polymer prepared by high internal phase emulsion. • Stearic acid and epoxy soybean oil were adopted to achieve superhydrophobic polyHIPE (161°). • Superhydrophobic polyHIPE with robust mechanical durability and chemical resistance. • Excellent absorption capacity (28.28 g/g) and high separation efficiency (99.42 %) for polyHIPE. [ABSTRACT FROM AUTHOR]

Glyphosate is a globally dominant herbicide. Here, we studied the degradation and microbial response to glyphosate application in a wetland soil in central Delaware for controlling invasive species (Phragmites australis). We applied a two-step solid-phase extraction method using molecularly imprinted polymers designed for the separation and enrichment of glyphosate and aminomethylphosphonic acid (AMPA) from soils before their analysis by ultra-high-performance liquid chromatography (UHPLC) and Q Exactive Orbitrap mass spectrometry methods. Our results showed that approximately 90 % of glyphosate degraded over 100 d after application, with AMPA being a minor (<10 %) product. Analysis of glyphosate-specific microbial genes to identify microbial response and function revealed that the expression of the phn J gene, which codes C-P lyase enzyme, was consistently dominant over the gox gene, which codes glyphosate oxidoreductase enzyme, after glyphosate application. Both gene and concentration data independently suggested that C-P bond cleavage—which forms sarcosine or glycine—was the dominant degradation pathway. This is significant because AMPA, a more toxic product, is reported to be the preferred pathway of glyphosate degradation in other soil and natural environments. The degradation through a safer pathway is encouraging for minimizing the detrimental impacts of glyphosate on the environment. [Display omitted] • Identified the occurrence of benign degradation pathways of glyphosate in soils. • Expression of the phnJ gene confirmed the dominance of C-P bond cleavage. • Suppressing AMPA production is most favored for protecting the environment. [ABSTRACT FROM AUTHOR]

The rapid rise of oil and gas, petrochemical, food processing, and pharmaceutical industries has added a complex mixture of contaminants like oil, particulates, metals, and other organic compounds to wastewater. Multipurpose membranes with precise pore structure can offer a solution to this problem and block copolymers (BCP) can be used to achieve such structures. Achieving vertical assembly of BCP domains provides a perfect template for developing uniform through film channels for separation and transport of material, besides being useful for the rectification of defects in photolithography patterns. Producing such morphologies may require extensive film/substrate processing and is not always feasible for scale-up. With this article, we demonstrate a facile solution casting method to induce vertical domain assembly in as-cast diblock copolymer thin films in the presence of an ionic liquid (IL) additive that preferentially segregates to one block and neutralizes interfacial interactions. We also show the tunability of domain sizes by controlling the additive concentration. These vertically aligned morphologies are important for the development of next-generation lithographic techniques and form excellent templates for ultrafiltration membranes with uniform pore sizes. This article demonstrates how IL additives can be used to obtain stable non-equilibrium morphologies in as-cast BCP films and the effect of BCP molecular mass, block volume fractions, and IL content on self-assembly. Figure TOC. Time-of-flight secondary ion mass spectroscopy depth profile for PS-b-PMMA (55 k-b-22 k) thin films with 50 mass% IL content and producing vertical cylindrical assembly in as-cast films (AFM phase image in the inset) for application as ultrafiltration membranes for polymer separations. [Display omitted] • One-step casting method to order block copolymers in as-cast films. • Fully perpendicular domain orientation for films doped with high quantities of ionic liquid. • Tunable domain sizes controlled by ionic liquid content of the films. • One-step self-assembly for very high molecular mass block copolymer films. • Perpendicular order translated to isoporous membranes for versatile separations like polymers, biomolecules, and oil/water. [ABSTRACT FROM AUTHOR]

Hydrogen isotopes are a valuable source of hydrogen energy through fusion reactions. The materials used in polymer electrolyte fuel cells (PEFCs), such as the hydrophobic support and Pt catalyst, are essentially the same to those used in the conventional isotope-separation method by water–hydrogen chemical exchange. Here, deuterium (D) separation was performed with a PEFC. A gas mixture of H 2 and D 2 was supplied while changing the humidity. The hydrogen gas and water vapor from the PEFC were analyzed to investigate the D mass balance. Without power generation, D was separated into the water vapor. This can be explained by the vapor-phase catalytic exchange reaction occurring on the platinum catalyst. The fuel-cell reaction enhanced D separation. A large amount of D (approximately 45%) was transferred to the water vapor during power generation. The present results demonstrate the synergistic effect of vapor-phase catalytic exchange and the PEFC on D separation. • Deuterium separation by polymer electrolyte fuel cell was studied. • The effect of the water vapor on the isotope separation was discussed. • The D mass balance clarified the breakdown of D/H ratio in the outlet gas and produced water. [ABSTRACT FROM AUTHOR]

A low-cost ceramic membrane was coated with cellulose acetate (CA) using different polymer concentrations and dipping durations. The porosity of the membrane decreased considerably (from 58.4 % to 12.1 %) with an increase in polymer concentration from 2.5 to 10 wt. %. The values of the porosity increased and layer thickness decreased slightly with a decrease in dipping time (from 60 s to 15 s). The membrane prepared using 5 wt. % CA in acetone and 45 s dipping duration (T-3) had a polymer separation layer of thickness 14.2 µm and was found to be optimal with 51.8 % porosity, 35 nm pore diameter and a liquid (water) permeability of 7.39 × 10–10 m3/m2·s·Pa. This membrane was applied for micellar enhanced ultrafiltration of three heavy metal ions, namely, Cu(II), Cr(VI) and Ni(II). The prepared membrane (T-3) was highly effective in ultrafiltration applications as evidenced from complete rejection (≈ 100 %) of cetylpyridinium chloride (CPC) along with satisfactory removal (>99.7 %) of metal ions. [Display omitted] • The pore characteristics were affected by polymer concentration and dipping duration. • A polymer concentration of 5 wt. % and dipping duration of 45 s yielded the best membrane. • Complete rejection of cetylpyridinium chloride was achieved with composite membrane. • More than 99.7 % average rejection of Cu(II), Cr(VI) and Ni(II) was achieved at 1.7 bar. [ABSTRACT FROM AUTHOR]

Extraction of cellulose and hemicellulose from natural resources has attracted considerable interest. In comparison to other cereals, there is relatively little knowledge on the cellulose, hemicellulose and lignin content of sorghum by-products. As such, the aims of this study were to develop a multi-step process for sorghum by-products (bran, stalk and panicles) fractionation and characterise them with regards to their physicochemical properties. In terms of chemical composition, sorghum panicles were found similar to bran, featuring a significant presence of arabinoxylans as well. A sequential alkaline extraction with varying concentrations of NaOH was applied, resulting in the generation of three fractions (residue, hemicellulose and alkali soluble lignin). Fractionation of sorghum stalks with 1.0 M NaOH at 50 °C for 3 h obtained -64 % (w/w) cellulose rich fraction and 52 % (w/w) of xylose, predominant in the hemicellulose fraction. In the bran, the fractionation with 0.75 M NaOH at 50 °C for 3 h obtained -40 % (w/w) cellulose rich fraction. Approximately 76 % of the glucose was in hemicellulose fraction reflecting starch solubilisation in the case of bran, while nearly 2 % (w/w) alkaline-soluble lignin was extracted. Overall, this study demonstrated an effective approach for the fractionation and the recovery of key components in sorghum by-products. [ABSTRACT FROM AUTHOR]

A creative dual-template molecularly imprinted polymer (Fe 3 O 4 @MCM-41-MIPs) with good magnetic properties and specific recognition of echinacoside and acteoside was prepared by surface imprinting. Echinacoside and acteoside served as dual templates, 4-vinylpyridine (4-VP) was used as a functional monomer, the cross-linker was ethylene glycol dimethacrylate (EGDMA), and the selected initiator was azobisisobutyronitrile (AIBN). The prepared Fe 3 O 4 @MCM-41-MIPs were applied to the selective separation and enrichment of echinacoside and acteoside from Cistanche deserticola Y. C. Ma (C. deserticola). The resulting Fe 3 O 4 @MCM-41-MIPs were characterized by scanning electron microscopy (SEM), transmission electron microscopy (TEM), Fourier transform infrared spectroscopy (FT-IR), laser particle size scanning and vibration sample magnetometry (VSM). The results of the isotherm adsorption experiment showed that the maximum adsorption capacities of Fe 3 O 4 @MCM-41-MIPs for echinacoside and acteoside were 6.02 and 1.63 mg·g-1, respectively, at 298 K. The pseudo-second-order reaction mechanism showed that the equilibrium adsorption capacities of Fe 3 O 4 @MCM-41-MIPs for echinacoside and acteoside were 4.81 and 0.93 mg·g-1, respectively. The characterization of Fe 3 O 4 @MCM-41-MIPs showed that the imprinted layer with dual-template molecules was wrapped on the outside of the carrier, and the obtained Fe 3 O 4 @MCM-41-MIPs showed good saturation magnetization, desirable capacity for echinacoside and acteoside adsorption, and satisfactory reuse (echinacoside and acteoside maintained relative adsorption rates of 97.5% and 95.8% after five cycles). After separation, the purities of echinacoside and acteoside were 33.50% and 27.00%, respectively. In addition, in the selective adsorption experiment, the synthesized Fe 3 O 4 @MCM-41-MIPs showed better selectivity for echinacoside and acteoside than their structural analogs. Therefore, this method proved to be sustainable, rapid and highly efficient for the separation and enrichment of echinacoside and acteoside. [Display omitted] • Fe 3 O 4 @MCM-41-MIPs based on dual-molecular was prepared and characterized. • Fe 3 O 4 @MCM-41-MIPs showed good selective extraction and enrichment for target compounds. • Fe 3 O 4 @MCM-41-MIPs exhibited a good magnetic property for rapid extraction. • Fe 3 O 4 @MCM-41-MIPs was proved to be simple, selective and recyclable material. [ABSTRACT FROM AUTHOR]

Magnetic levitation (MagLev) is a well-documented and widely-applied technique in accurate, sensitive, and untethered testing of living and non-living materials in both macroscale and microscale. However, most magnetic levitation configurations face the dilemma between working range and sensitivity, since the distance between the two like-pole-facing magnets are in positive relationship with sensitivity, but negative with measuring range. And there exists a maximum distance for MagLev configurations where the misalignment happens when the distance is too large, which is a restriction on the working space and measurement range of the MagLev devices. In this paper, we propose a novel configuration based on the principle of Halbach array, namely the Cross-Halbach MagLev configuration. By doing parallel comparisons with the Standard MagLev consisting of magnets of the same size, we determined the superiority of the Cross-Halbach configuration in magnetic flux density (0.47 T) and B → ∙ ∇ B → z (6.25 T2/m), maximum distance (90 mm), sensitivity (525 mm/(g/cm3)) and wide linear zone on B → ∙ ∇ B → z (42 mm). To demonstrate and further explore the potential of the Cross-Halbach MagLev, we carried out a series of experiments, including density measurements of standard beads and different polymers, detection and separation of similar polymers with minute difference in density, and nondestructive detection of voids. The results indicate that the proposed magnetic levitation configuration is competent of density-based applications and can serve as a new solution to high-sensitivity measurement and detection. • Designed and built a novel Cross-Halbach MagLev device. • The superiority of the device was showcased by parallel comparison with Standard MagLev. • The enhanced performance of the Cross-Halbach configuration was demonstrated via density-based experiments. [ABSTRACT FROM AUTHOR]

Advancements in membrane separation technology play a pivotal role in separation processes closely associated with the environment and energy. However, presently available commercial polymeric membranes encounter the challenge of low permeability, impacting both separation efficiency and membrane module costs. Here, we propose a simple and effective in situ acid hydrolysis strategy to significantly enhance membrane permeability. Specifically, a tetrafluorinated monomer with hydrolyzable Schiff base groups (TFNAD) has been meticulously designed, synthesized, and copolymerized with commercial TFTPN and TTSBI, yielding a series of copolymers. Subsequently, in situ hydrolysis removes aniline from the membrane, freeing up the occupied free volume and creating additional channels for gas transport. This process substantially enhances gas permeability while preserving the desired selectivity. PIM-TFAD-30 showed a 68 % improvement in CO 2 permeability with virtually no compromise in CO 2 /N 2 selectivity compared to the pre-hydrolysis membrane. Meanwhile, PIM-TFAD-30 also displayed outstanding separation performance and plasticization resistance in simulated flue gas tests, demonstrating its potential for practical application. This facile and straightforward hydrolysis method opens up a new perspective for preparing and modifying polymeric separation membranes beyond gas separation. [Display omitted] • A simple and effective strategy for in situ acid hydrolysis is presented. • Hydrolysis significantly enhances the gas permeability of the membrane while maintaining almost identical selectivity. • In situ hydrolysis strategy offers a novel perspective on the design of superior gas separation membranes. [ABSTRACT FROM AUTHOR]

Carbon molecular sieve (CMS) membranes demonstrate promising economic and environmental advantages in gas separation applications. In this work, we synthesized a novel polymer precursor of PEK-N and utilized it to fabricate a series of PEK-N derived CMS membranes. With varying carbonization temperature and time, the pore structures and gas separation performance were finely tuned. The gas separation properties of membranes with different carbonization temperature were comprehensively evaluated. In particular, by carbonizing the sample at 650 °C for 1 h, PEK-N derived CMS membranes (CMS-650-1) achieved the highest CO 2 permeability around 2176 Barrer, and selectivities of 48.2 for CO 2 /N 2 and 57.8 for CO 2 /CH 4 in their gas mixtures. Our study suggests that the use of rationally designed polymers has the potential to bring about high gas separation performance for polymer-derived carbon molecular sieve membranes. This study explores the use of a novel polymer of polyaryletherketone bearing tertiary amine group (PEK-N) for preparing carbon molecular sieve membranes through control of carbonization temperature and time. The optimized CMS membrane (CMS-650-1) exhibited a CO 2 permeability around 2176 Barrer, and CO 2 /N 2 and CO 2 /CH 4 gas selectivities of 48.2 and 57.8, respectively. [Display omitted] • Polyaryletherketone bearing tertiary amine group polymer was synthesized. • CMS membranes were fabricated using PEK-N polymer. • The structural features of CMS membranes could be tuned by adjusting the carbonization temperature and time. • The CMS membrane exhibited high separation performance for CO 2 /N 2 and CO 2 /CH 4. [ABSTRACT FROM AUTHOR]

• Mullite-based ceramic composite membranes were developed by combining in-situ growth of ZIF-8 and coating of ZIF-8-doped PDMS. • The mullite-based ceramic composite membranes exhibited good gas separation properties and thermal stability. • The M/ZIF-8/PDMS@ZIF-8 demonstrated a high CO 2 permeance of 3050 GPU and superior CO 2 /N 2 selectivity of 10.7. • The M/ZIF-8/PDMS@ZIF-8 exhibited excellent CO 2 separation stability at 80 °C. The development of high-performance composite membranes for efficient CO 2 /N 2 separation is essential for reducing CO 2 emissions. However, achieving a balance between permeance and selectivity remains a challenge. In this work, two CO 2 permeable mullite ceramic-based composite membranes were made using fly ashes and α-Al 2 O 3 as raw materials for mullite substrates, ZIF-8 nanofillers, and PDMS rubber polymer as gas separation materials. To enhance CO 2 permeance and CO 2 /N 2 selectivity, the M/PDMS@ZIF-8 composite membrane was prepared by dip-coating a ZIF-8 doped PDMS active layer (PDMS@ZIF-8) on the surface of the mullite-based substrate (M 0). Subsequently, the M/ZIF-8/PDMS@ZIF-8 composite membrane was fabricated by in-situ growing ZIF-8 and followed by coating a PDMS@ZIF-8 functional layer on the M 0 surface. The results indicated that the optimal M/PDMS@ZIF-8 membrane with 1 % of ZIF-8 exhibited an ultrahigh CO 2 permeance of 4756 GPU and a good CO 2 /N 2 selectivity of 10.07 at room temperature under 0.2 MPa. While the optimized composite membrane M/ZIF-8/PDMS@ZIF-8 with 0.8 wt% of ZIF-8 achieved a high CO 2 permeance of 3050 GPU and superior CO 2 /N 2 selectivity of 10.7. Furthermore, the latter displayed long-term permeation stability at 80 °C. The facile preparation process and cost-effective nature of the ceramic-based composite membrane demonstrate great potential for applications in CO 2 capture from flue gas. [ABSTRACT FROM AUTHOR]

• The H 2 /CO 2 separation performance of benzimidazole-linked polymer membrane (BILP-101x) was regulated through controlling the interfacial polymerization reaction time. • The microstructure of BILP-101x membrane were systematically characterized. • The BILP-101x membrane can withstand high temperature and pressure. • The H 2 /CO 2 separation mechanism of BILP-101x membrane was investigated through molecular dynamic simulations. • The membrane also exhibits excellent separation performance towards H 2 /N 2 and H 2 /CH 4. Separation of hydrogen from carbon dioxide for sustainable H 2 production and CO 2 capture still faces great challenges due to the smaller size of H 2 and higher condensability of CO 2. Herein, a high-performance benzimidazole-linked polymer (BILP) membrane for hydrogen separation was directly prepared on α-Al 2 O 3 substrate through a facile interfacial polymerization approach at room temperature. The separation performance of the BILP membrane were regulated by controlling the reaction time and the microstructure was systematically characterized. Molecular simulations were performed to deep understand the separation mechanism in the BILP membrane. The best performance membrane displays an extraordinary mixed gas selectivity of 40 for H 2 /CO 2 together with outstanding H 2 permeance of 250 gas permeation units (GPU) at 473 K, far exceeding the Robeson's upper bound. Besides, the membrane can withstand high temperature and pressure, and also shows good H 2 /N 2 and H 2 /CH 4 selectivity. The excellent separation performance, coupled with high temperature and pressure resistance and easy preparation, render BILP membranes great potential for economic H 2 purification, H 2 recovery, and natural gas treatment. [ABSTRACT FROM AUTHOR]

In this paper, the growth of finger-like droplets inside various polymer membrane embryos induced by non-solvent phase separation (NIPS) is studied in details by using a standardized optical microscopic observation method. The boundary conditions of the phase separation are well-defined by microfluidics technology. The growth of finger-like droplets and Marangoni convection inside them are tracked and recorded by high-speed camera of sharp resolutions. Effects of the geometry of the membrane embryos (thickness/shape/size), humidity of the atmosphere and the viscosity of the embryos on the growth of finger-like droplets are systematically studied. Except the qualitative observations that are consistent to previous relative reports, more quantitative data are provided in this paper. The diffusing speed of the interface of the developing large droplets is measured by template matching algorithm. Strikingly, the time-dependent diffusing speed of the developing large droplets shows a wave-like declining pattern, which indicates that fluctuating boundary conditions are surrounding the membrane embryos. The Reynolds number of the flow inside the developing large droplets is estimated at the order of 10−5, the magnitude of which is 2 order smaller than that of a swimming sperm. [Display omitted] • The traditional optical direct observation method is improved to study the growth of finger-like droplets. • Both quantitatively and qualitative data are provided to illustrate the growth dynamics of finger-like droplets. • Macro-flows (Marangoni convection) inside the developing large droplets are clearly observed and analyzed. [ABSTRACT FROM AUTHOR]

[Display omitted] Polymer materials have been extensively utilized in diverse separation fields, especially in membrane-based nanotechnologies for gas and liquid separations. The membrane separation has proven to be highly promising to address energy, resource, and environmental challenges. However, progress in polymer separation membranes has been constrained by its inherent limitation that is the trade-off relationship between permeability and selectivity. Polymers of intrinsic microporosity (PIMs), as promising building materials have received substantial attention for membranes separation over the last decade. Different from conventional polymers, PIMs are a new class of microporous polymer materials that possess favorable solubility, well-defined pore architectures, and steerable post-modification due to the designability of synthesis monomer at a molecular level. In this review, we first discuss the state of the art of PIMs-based separation membranes and highlight their critical merits for membrane design. We then describe rational strategies towards fabricating PIM-based membranes and their applications, with a focus on the recent advances in gas separation, pervaporation (PV), nanofiltration (NF) and organic solvent nanofiltration (OSN). Furthermore, the physical aging issue of PIMs and its advanced strategies are also discussed and summarized. Finally, a concise conclusion, current challenges, and future opportunities on the development of PIM-based membranes are additionally discussed. [ABSTRACT FROM AUTHOR]

• Thermal behavior is studied in the UHMWPE – dioctyl adipate mixture. • Increase in polymer molecular weight expectedly promotes LLPS. • Increase in cooling rate unexpectedly disfavors LLPS. • LLPS may be more kinetically dependent process than polymer crystallization. • UHMWPE – dioctyl adipate is a promising system for membrane preparation. The thermal behavior of ultra-high molecular weight polyethylene (UHMWPE) with dioctyl adipate (DOA) was investigated by the differential scanning calorimetry (DSC) method. Capillary-porous bodies were obtained via thermally induced phase separation of DOA mixtures with polyethylenes of different molecular weight at different cooling rates. Analysis of the morphology of the prepared porous bodies together with DSC data and results of cloud point estimation revealed an unexpected effect of a cooling rate on the type of phase separation occurring in the mixture during its cooling from homogeneous state. Particularly it was shown that increase in the cooling rate reduces the probability of realization of liquid – liquid phase separation in the mixture. It was argued that such behavior, different from the standard semicrystalline polymers, is a result of kinetic hindrance of liquid – liquid phase separation in mixtures containing a polymer with such a high molecular weight. [Display omitted] [ABSTRACT FROM AUTHOR]

[Display omitted] • CNC induces rapid phase separation of polymer and solvent during electrospinning. • TBAC makes the backbone fiber (1.17 μm) split into dendritic structure fibers (53.3 nm). • The fiber surface is composed of nanosphere structures and has excellent super-hydrophobicity. • The membrane exhibited rapid oil–water separation performance and cycle stability. Inspired by the multi-level structure of trees in nature, using cellulose nanocrystals/polyvinylidene fluoride (CNC/PVDF) fibers as the support layer and CNC/PVDF/organic branched salt (TBAC) fibers as the filtering layer, to construct oil–water separation membrane with tree-like structure. The membrane's surface (nano spherical) and internal (interconnected pores) structures were regulated by phase separation of CNC induced. The high conductivity of TBAC was utilized to construct branched fibers (d = 53.3 nm) on the backbone fibers (d = 1.2 μm). The impact of TBAC on the microstructure, wetting behavior, and oil–water separation performance of membranes was investigated. Note, TBAC concentration was 0.02 mol/L, the membrane exhibits a highly porous dendritic network structure (with porosity of 85 % and pore size of 6.1 nm), and outstanding wetting properties (water contact angle underoil ˃ 150°). This distinctive structure endows membranes with a high oil adsorption capacity (64.1 g/g of engine oil), oil flux (22873 L/m−2h−1 of toluene). Following ten testing cycles, the toluene adsorption capacity remains at 83.1 % of the initial adsorption, while the separation flux of emulsion (5645 L/m−2h−1) remains nearly constant. Overall, successfully fabricating CNC/PVDF/T-0.02 fibers with a tree-like structure provides a novel approach to designing and developing efficient membrane separation materials. [ABSTRACT FROM AUTHOR]

Over the past decades, there has been a flourishing of phase-separated polymer gels. Unlike traditional design methods that rely on chemical structure and polymer network construction, phase separation enables polymers to tune morphologies across the microscopic, mesoscopic, and macroscopic levels, thereby creating a new path for regulating and innovating the performance of polymer gels. This comprehensive review offers a deep dive into the mechanisms underlying phase separation formation in polymer gels and makes a particular focus on the methods used to induce phase separation in polymer gels. Additionally, the review highlights the potential performance improvements and innovations of polymer gels based on phase separation and explores the promising applications of phase separation polymers in various fields. Finally, this review emphasizes the potential benefits yet significant challenges associated with phase-separated polymer gels. The versatility and multi-scale applicability of this approach make it a promising pathway for developing cutting-edge materials with tailored properties and functionalities. [Display omitted] [ABSTRACT FROM AUTHOR]

Conventional polymer separation membranes or coatings suffer from poor separation performance and serious failure in highly corrosive environments, due to their low chemical and mechanical stability. Herein, a simple electrospraying and electrospinning strategy was used to prepare flexible superhydrophobic carbon fiber membranes (FSCFM). The wettability of FSCFM was improved by forming a lotus leaf-like hierarchical rough structure on its surface. The FSCFM exhibited an excellent permeation flux of immiscible oil-water mixtures (up to 15,800 L m−2 h−1) and water-in-oil emulsions (over 5500 L m−2 h−1), while the separation efficiencies were always kept at more than 99 % after 25 consecutive separations. Even in corrosive environments, its separation performance did not show any degradation. Notably, except for recovering floating oil under external driving forces with excellent cyclic stabilities, FSCFM was also able to transport various corrosive solutions with high efficiencies (99.9 %). After multiple mechanical damages and bending cycles, the FSCFM remained superhydrophobic. It could also maintain its repellency in strong acids/bases, high salt solutions and even under high-temperature environments (94.5 °C). These superior properties make it a strong candidate for oil-water mixture/emulsion separation and non-destructive transport of highly corrosive fluids. [Display omitted] • Flexible superhydrophobic carbon fiber with a lotus leaf structure. • Excellent separation capability of oil-water mixtures and emulsions. • The separation performance in highly corrosive environments remains unchanged. • Excellent mechanochemical robustness and multifunctionality were obtained. [ABSTRACT FROM AUTHOR]

[Display omitted] • ML model for permeability prediction of six common gases in polymers is constructed. • A framework combining ML and Bayesian-based polymer design algorithm is proposed. • Polymers above the CO 2 /CH 4 and CO 2 /N 2 upper bounds are predicted by the framework. • MD simulation is used to verify the gas permeability of selected polymer candidates. Designing polymers with desirable properties for gas separation membranes in a large chemical space is challenging. To address this issue, a framework combining machine learning (ML) and Bayesian-based molecular design algorithm is proposed to assist the discovery of polymers for gas separation membranes. In this study, explainable ML models for predicting gas permeability in polymers are developed and used to investigate the relationship between chemical structure and gas permeability. The Bayesian-based molecular design algorithm is further used to explore new polymers with properties above the current CO 2 /CH 4 and CO 2 /N 2 upper bounds. Hundreds of promising polymers with excellent CO 2 /CH 4 and CO 2 /N 2 separation performance are identified. Molecular dynamics (MD) simulations are used to calculate the gas permeabilities of the polymer candidates, providing additional support for the ML-predicted gas separation properties of polymer candidates. The polymer design framework presented in this work advances the discovery of polymers for gas separation membranes. [ABSTRACT FROM AUTHOR]

• Self-healing polyurethanes have incomplete ionized ionic groups. • Self-healing can be achieved at room temperature and accelerated dramatically in the presence of water. • Self-healing strengthening effect is achieved with self-healing efficiency of 104.72%. • Mechanism analysis by experiment and molecular dynamics (MD) simulations reveal the enhanced molecular movement and further ionized. Self-healing polymers with microphase separation structure typically require external stimuli to achieve self-healing, and their performance often degrades. To solve these issues, we introduce tertiary amine and carboxyl groups into polymer. The intermolecular ionic interactions and H-bonds contribute to the formation of microphase separation structures, endowing polyurethane elastomers (PU-n) outstanding mechanical properties with a maximum tensile strength and toughness of 20.61 MPa and 59.02 MJ/m3, respectively. The self-healing of the prepared PU-n can be achieved at room temperature and accelerated significantly by water because hard phases can be dissociated, resulting in enhanced molecular movement. After self-healing with water, the enhanced molecular movement and further ionization of ionic groups lead to stronger H-bonds and ionic interactions, promoting more distinct microphase separation. Thus, the mechanical strength is strengthened and the self-healing efficiency can reach 104.72 %. The enhanced molecular movement and strengthened intermolecular interactions when self-healing with water can also be verified through in-depth analysis of molecular dynamics (MD) simulations of the self-healing process. Furthermore, PU-n display remarkable shape memory and can be recycled through exposure to solvents and hot water. This study provides a novel and general method for preparing materials that can self-heal with water and self-strengthen after self-healing. [ABSTRACT FROM AUTHOR]

[Display omitted] • A new multi-template molecularly imprinted polymer was synthesized. • The adsorption capacity of the polymer for saponins was up to 74.825 mg/g. • Polymers are substantially more saponin-selective than homologues. • The polymer successfully extracted high-purity saponins from purple yam. • The polymer has a high extraction rate and a low extraction cost. Saponin is an essential natural compound in purple yams with high nutritional and medicinal value. In this work, a multitemplate molecule-imprinted polymer (MMIP) was synthesized with dioscin, protodioscin, and diosgenin templates. The MMIPs were characterized with scanning electron microscopy, thermogravimetric analysis, Brunauer–Emmett–Teller (BET) adsorption, and Fourier transform infrared spectroscopy. The efficacy of the MMIPs was assessed with static, dynamic, selective adsorption, desorption, and reusability experiments. The three saponins were selectively extracted and determined by MMIP-high-performance liquid chromatography. The polymer morphology was regular and spherical. The amount of the MMIP adsorbed was 74.825 mg/g, and the imprinting factor was 2.1. The MMIP adsorbed the three saponins from purple yam extract, with recovery rates of 95.5–103.43 % and desorption rates of 85 %–98 %. In addition, the MMIPs were reused at least six times. These results demonstrated that the MMIPs efficiently and selectively extracted dioscin, protodioscin, and diosgenin from food matrices at high rates. [ABSTRACT FROM AUTHOR]

[Display omitted] • Pebax/EVA were blended to optimize the separation of CH 4 /N 2. • The change of structure after blending shows the CH 4 permeability of 384.6 Barrer. • The CH 4 /N 2 selectivity of blend membrane is increased by 35.5% by blending. • The properties satisfy the requirements of the novel natural gas leak detection. The CH 4 /N 2 high-efficiency membrane separation technology is capable of effectively enriching CH 4 from natural gas, and holds great potential for application in the fields of biogas purification and natural gas pipeline leak detection. However, preparing high-performance separation membranes is challenging due to the similarity between CH 4 and N 2 molecules. To enhance the CH 4 /N 2 separation performance, block polyetheramide copolymer (Pebax)/EVA blended membranes were fabricated in this study. Additionally, a novel gas leakage detection tube was prepared. The EVA14 (14 wt% VA) membrane exhibits an optimal transport-facilitated channel among a series of pure EVA membranes, resulting in a CH 4 permeability of 21.41 Barrer and CH 4 /N 2 selectivity reaches 1.80 under mixed-gas feed conditions at 35 °C. The CH 4 permeability of Pebax/EVA (30 wt%) reaches 120.5 Barrer by physical blending, and the CH 4 permeability is increased by 191 % in comparison with pure EVA14 membrane. The Pebax/EVA (10 wt%) membrane exhibits the optimum CH 4 /N 2 selectivity, and compared with pure EVA membrane increased by 35.5 %. EVA and Pebax polymers are blended for the first time for CH 4 /N 2 separation, and the blending of block polyetheramide copolymer intensifies the membrane's separation performance comprehensively. The natural gas leak detection tube was fabricated with a membrane, offering a new and efficient CH 4 /N 2 separation strategy. [ABSTRACT FROM AUTHOR]

The preparation of high-performance H 2 /CO 2 polymer separation membranes is an urgent need to reduce the global greenhouse effect. Here, polyamide (PA) membranes with excellent H 2 /CO 2 separation performance are produced using a facile interfacial polymerization (IP) plus heat treatment approach. The synergistic effect of the substrate-confinement and the control of the d-spacing and crosslinking degree of PA membranes creates sufficient H 2 selective channels. The effects of test parameters such as feed temperature and feed pressure on membrane performance were investigated. The ultra-high H 2 /CO 2 selectivity of 110 with excellent H 2 permeance of 180 GPU is observed at 150 °C and feed pressure of 2 bar. In addition, PA membranes have high-pressure resistance (16 bar), high-temperature resistance (300 °C), and attractive durability (210 h). The excellent performance and facile preparation process make them expected to be one of the most promising membranes for H 2 /CO 2 separation. [Display omitted] • Sufficient H 2 -selective channels are created in PA membranes via molecular-level manipulation. • Substrate-confinement as well as the control of d-spacing and cross-linking degree are utilized as strategies. • The membranes manifest outstanding H 2 /CO 2 selectivity (up to 110) and H 2 permeance (up to 180 GPU). • The membranes have high-pressure resistance (16 bar) and high-temperature resistance (300 °C). • The membranes have attractive durability (210 h). [ABSTRACT FROM AUTHOR]

Smart gating membranes have drawn much attention due to the controllable pore structure. Herein, a smart gating membrane with dual responsiveness was prepared from bacteria cellulose (BC) grafted with pH- and temperature-responsive polymers. By external stimulation, the average pore size of the membrane can be controlled from 33.75 nm to 144.81 nm, and the pure water flux can be regulated from 342 to 2118 L·m−2·h−1 with remarkable variation in the pH range of 1–11 and temperature range of 20–60 °C. The adjustability of pore size is able to achieve the gradient selective separation of particles and polymers with different sizes. In addition, owing to the underwater superoleophobicity and the nanoscale pore structure, the membrane separation efficiencies of emulsified oils are higher than 99 %. Moreover, the controllable pore size endows the membrane with good self-cleaning performance. This nanocellulose-based smart gating membrane has potential applications in the fields of controllable permeation, selective separation, fluid transport, and drug/chemical controlled release systems. [Display omitted] [ABSTRACT FROM AUTHOR]

While significant advancements have been made in the synthesis of microporous polymers for gas separations in the last two decades, little is known regarding structure–property relationships under industrially relevant conditions involving highly condensable gases such as H 2 S. Recent work on the mixed-gas transport in an amine-functionalized microporous PIM (PIM-NH 2) has demonstrated benefits of simultaneous plasticization resistance and competitive sorption for increased permselectivity in binary CO 2 /CH 4 mixtures. In this work, we elucidate the effects of analogous competitive sorption relationships through pure- and mixed-gas permeation in an amine-functional microporous poly(aryl ether) (PAE-NH 2) and provide comparisons with PIM-NH 2 and the corresponding nitrile-functional counterparts, PAE-CN and PIM-1. In binary mixed-gas tests, PAE-NH 2 show a 2.5- and 2.4-fold increase in CO 2 /CH 4 and CO 2 /N 2 mixed-gas permselectivities, respectively, compared to the pure-gas case. In 20/20/60 H 2 S/CO 2 /CH 4 mixtures, amine-functionalized derivatives retain increases in CO 2 /CH 4 selectivities compared to the nitrile-functional analogues. Additionally, PIM-NH 2 , PAE-CN, and PAE-NH 2 have excellent plasticization resistance in 50/50 CO 2 /CH 4 binary mixed-gas tests up to 26 atm. [Display omitted] • PIM-1, PAE-CN, and amine-functional (PIM-NH 2 , PAE-NH 2) polymers were measured in CO 2 /CH 4 , CO 2 /N 2 , H 2 S/CO 2 /CH 4 mixtures. • Competitive sorption was observed in all four materials, but effects were most apparent in the amine-functional membranes. • CO 2 - and H 2 S-based permselectivities increased from pure- to mixed-gas tests due to exclusion of N 2 /CH 4 from the polymer. • The amine-functional materials demonstrated excellent plasticization resistance up to 26 atm in a 50/50 CO 2 /CH 4 mixture. [ABSTRACT FROM AUTHOR]

Although polymers tend not to mix, it remains challenging to characterize the immiscibility of enantiomeric poly(ʟ-lactide) (PLLA) and poly(ᴅ-lactide) (PDLA), particularly with equivalent and high molecular weight (high MW), which frustratingly disfavors the exclusive stereocomplexation. By introducing a random copolymer (PLC) of ʟ-lactide and caprolactone to form binary blends with PLLA and PDLA, the phase behavior of high-MW PLLA/PDLA blends was investigated mainly by using differential scanning calorimetry (DSC) and atomic force microscopy (AFM). DSC results showed that PLLA/PLC blends exhibited a single glass transition temperature (T g), which depended on the blending ratio and precisely corresponded with the theoretical values calculated from the Fox equation. In comparison, PDLA/PLC blends showed composition-dependent heat-capacity increment at two unchanged T g values of pure PLC and PDLA. AFM observation revealed that PLC is completely miscible with PLLA at high MW but is immiscible with PDLA, logically suggesting immiscibility of high-MW PLLA and PDLA. Moreover, AFM results demonstrated that high-MW PLLA/PDLA blends exhibited spherical droplets in asymmetric blends and bicontinuous interpenetrating worm-like patterns in symmetric counterparts, showing distinct and well-defined interfaces, confirming the microphase separation. Additionally, different MWs fundamentally led to significant differences in miscibility, which consequently affected the crystallization behaviors of PLLA/PDLA blends. This work provides evidence for (im)miscibility and its crucial impact on the crystallization of PLLA/PDLA blends and has important implications for understanding the stereocomplexation of polymers. [Display omitted] [ABSTRACT FROM AUTHOR]

• Separation and recovery of polymeric fractions as backsheet and encapsulant. • Recycling of metallic silver and silicon from EVA residue. • 82% recycling rate, 94% recovery rate and 73% value recovery for EOL PVP treatment. The increase in the annual flux of the end-of-life photovoltaic panels (EoL-PVPs) imposed the development of effective recycling strategies to reach EU regulation targets (i.e. 80% recycling; 85% recovery, starting from August 2018). The recycling targets in a PVP are generally glass, photovoltaic cell and metals, while no scientific paper or patent addressed polymeric fractions recycling and recovery, i.e. encapsulant polymer (EVA) and backsheet (Tedlar), starting from preliminarily milled EoL-PVPs. In the present study an optimization following the solvent treatment operation of the basic Photolife process (demonstrated at pilot scale), was proposed (lab scale) and validated (micropilot scale), focusing on polymers separation and metals recovery. The optimization was performed by testing 4 different processes. Specifically, the selectivity of the filtration operation (subsequent the solvent treatment) on polymers separation grade was evaluated, demonstrating that Tedlar can be effectively separated from EVA residues. Moreover, in comparison to the basic Photolife, a further operation was introduced treating thermally the EVA residues (containing the PV cell). The metal extraction yields highlighted the effectiveness of that strategy in comparison with direct extraction from the uncombusted EVA residues. Processing 100 Kg of crushed material, 0.03 Kg of Ag, 45.5 Kg of high value glass, 10 Kg of Al scraps and 1.2 Kg of metallic filaments can be recovered. Thanks to the optimization the recycling rate of the implemented process grew up to 82% (75% during demonstration of the basic Photolife process), while the recovery was estimated at 94%. Remarkably, these rates get over with EU Directive. [ABSTRACT FROM AUTHOR]

Nowadays most membrane separation processes utilize membranes made from organic polymers because shape and structure can be tailored to the needs of a specific application with scalable fabrication processes such as solution casting and phase separation, coating and interfacial polymerization. This short review discusses recent progress for membranes suited for molecular separation in aqueous and organic liquids by nanofiltration, dialysis, electrodiaysis or pervaporation. Important achievements for bulk polymers suited as membrane material have been made by special processing of cellulose, development of highly stable polymers, microporous polymers and microphase-segregating copolymers. Ultrathin barrier layers are critical to combine target selectivity with high flux. Hence the scope of layer-by-layer and self-assembly of polymers as well as interfacial polymerization of standard monomers and advanced building blocks has been expanded, with the aim to obtain in situ on supports microporous materials with suited functional groups or molecular cavities. Overall, there is an increasing number of approaches which enable a precise tailoring of selectivity and boosting the flux at the same time. Hence, much higher overall separation performance compared to state-of-the-art membranes is in principle feasible. [ABSTRACT FROM AUTHOR]

Polymer membranes are widely utilized in industrial separation processes. Along with numerous experiments conducted for gas and liquid separations, molecular simulations have also been performed to fundamentally elucidate separation mechanisms in polymer membranes. However, the simulation studies are mostly limited to gas and aqueous mixtures, and non-aqueous separations such as pervaporation and organic solvent nanofiltration are less or largely unexplored. In this review, the recent simulation studies on liquid separations in polymer membranes are critically reviewed. First, various rational design strategies to tune the performance of polymer membranes for water desalination are outlined. Then, new simulation protocols and computational characterization methods are presented for pervaporation and organic solvent nanofiltration. These bottom-up studies provide a rich landscape of microscopic insights into the separation mechanisms and processes of liquid mixtures in polymer membranes, which will facilitate the rational screening and design of high-performance polymer membranes for liquid separations. [ABSTRACT FROM AUTHOR]

In this study, we analyzed the effect of human body secretions on the transport and separation properties of membranes with high distribution properties (nanofiltration/reverse osmotic membranes). The problem of low molar mass disinfection by-products is an important issue from the point of view of public health. Therefore, it is necessary to take measures to modernize the pool water treatment circuits in-line with low-waste technologies. The pressure membrane processes presented in this study were characterized by the higher retention of impurities which is characteristic of pool water (e.g., urea, creatinine, and uric acid). In addition, the transport properties of pool water were found to be good with polyamide reverse osmosis (AFC80) membrane, which was slightly altered during the filtration cycles. It should be emphasized that an important factor that allowed to maintain high values of the volumetric permeate flux was the periodic replenishment of the feed with a fresh dose of tap water. Creatinine potentially contributes to the blocking of AFC80 membrane pores. In this study, citric acid (1% solution) was not effective in cleaning the reverse osmosis membranes. [ABSTRACT FROM AUTHOR]

Thermal field-flow fractionation (ThFFF) was successfully coupled online to size exclusion chromatography (SEC) in a comprehensive two-dimensional configuration. In the first dimension, fractionation according to chemical composition based on the interplay of thermal and translational diffusion took place in the ThFFF channel. Fractions from the first dimension were comprehensively transferred to the second dimension, SEC, and separated according to hydrodynamic volume which is a function of molar mass. To illustrate the capabilities of this novel two-dimensional fractionation approach, polystyrene-poly (methyl methacrylate) block copolymers were comprehensively fractionated and characterized. Blends of homopolymers, homo- and copolymers, and copolymers with different compositions were fractionated and the effects of experimental conditions, the components' molar masses and compositions were investigated. The results illustrated the molar mass independence of the thermal diffusion coefficient in ThFFF. Translational diffusion coefficients were quantitatively determined via dynamic light scattering. The study aimed at proving the versatility of the comprehensive online coupling of ThFFF and SEC for the analysis of complex polymers having the ability to provide detailed molecular information (chemical composition and molar mass distribution) as well thermal and translational diffusion information in a single analysis. Finally, the merits of using information-rich detectors are highlighted. Image 1 • As a novel analytical approach, ThFFF has been coupled comprehensively and online with SEC. • The advantages of ThFFF X SEC for the separation of complex polymers such as PS- b -PMMA block copolymers are demonstrated. • The developed method simultaneously provides molecular information, the thermal and translational diffusion coefficients. [ABSTRACT FROM AUTHOR]

High-flux polyvinyl chloride (PVC) membranes with hydrophilic interpenetrating networks were fabricated by a 'green' (without toxic initiator) in-situ method in this study. The interpenetration between the polyvinyl chloride (PVC) molecules and the hydrophilic network was formed during the phase separation process, where the cross-linking was initialized by water in a solidification bath between siloxanes in aminopropyltrimethoxysilane-b-poly (ethylene glycol) diglycidyl ether synthesized in the PVC dissolution process. From the reconstruction of the PVC membrane, high hydrophilicity and porosity, and narrow pore size distribution have been achieved. As results, compared to the pristine membrane. the pure water flux was increased 17 times to 1177.4 L m−2 h−1, the flux recovery rate was increased by 15.9 %, and the strength was also increased slightly. [Display omitted] • A-P hydrophilic functional molecules were synthesized synchronously during polymer dissolution. • Polymer/A-P interpenetrating networks were formed during polymer phase separation. • Membranes with persistent hydrophilicity and uniform pore size were fabricated via polymer/A-P interpenetrating networks. • Pure water flux and anti-fouling performance of membranes were significantly improved. [ABSTRACT FROM AUTHOR]

Gas separation properties are reported for self-standing polymer of intrinsic microporosity (PIM) films after addition of palladium (II) acetate or iron (II) acetate by solid state or liquid state mixing. Membranes, with thicknesses in the range 35–55 μm, were prepared from three high molar mass PIMs, two different branched versions of the much-reported PIM-1 (PIM-1a and PIM-1b) and of PIM-Py. Addition of either Fe(OAc) 2 or Pd(OAc) 2 to all three PIMs led to a reduction in permeability and increase in selectivity, but the permeability reduction was much greater for Pd(OAc) 2 , which is able to interact with branch points in the PIM and crosslink the polymer. CO 2 /CH 4 selectivity of membranes containing Pd(OAc) 2 was poor upon aging, especially after solid state addition to the PIM-1 polymers, for which CO 2 permeabilities dropped to below 200 Barrer after 85 days. Hydrogen permeability and H 2 /N 2 selectivity of membranes containing Pd(OAc) 2 did more closely follow conventional permeability/selectivity trade off upon aging. This illustrates the profound differences that can arise in gas permeation properties and aging behaviour from variations in chemical structure and macromolecular characteristics, and from the addition of metal acetates that interact with the polymer in different ways. [Display omitted] • Branched PIM-1 crosslinked with Pd(OAc) 2 produced membranes with reduced permeability. • Loss in CO 2 permeability on aging not matched with increase in CO 2 /CH 4 selectivity. • Loss in H 2 permeability on aging matched with increase in H 2 /N 2 selectivity. • Crosslinks block smaller free volume elements that dominate CO 2 /CH 4 selectivity. • Fe(OAc) 2 mixed PIM-1 membranes maintain permeability/selectivity balance. [ABSTRACT FROM AUTHOR]

• Dual-responsive block copolymer P(St-MAn-DMAEMA) was designed and synthesized. • An OT-CEC protocol was developed for chromones separation with P(St-MAn-DMAEMA)-coating. • Separation performance of OT-CEC was greatly improved by varying pH and temperature. • The proposed OT-CEC assay was applied in analysis of chromones in urines. Fabricating polymeric coatings that are responsive to multiple/dual stimuli is crucial and remains a major challenge in the development of highly efficient open tubular capillary electrochromatography (OT-CEC). In this study, a pH and temperature-responsive block copolymer, poly(styrene-maleic anhydride 2-dimethylamino ethyl methacrylate), P(St-MAn-DMAEMA), was designed and synthesized. Using P(St-MAn-DMAEMA) as the coating, an OT-CEC protocol was constructed for the analysis of chromones. The morphology and hydrophobicity-hydrophilicity of the polymeric coating could change via varying the environmental conditions, affecting the separation efficiency of OT-CEC. Interestingly, the best performance of OT-CEC was achieved at pH 9.7 and 45 °C via tuning the interactions between the coating and the analytes. Additionally, the proposed OT-CEC method exhibited a good linear range for the detection of the three test chromones from 10.0 to 100.0 μM, with all correlation coefficients (R2) >0.997. The coatings also had good stability and reusability. This work provides an approach for the preparation of new multiple-stimuli-responsive polymeric coatings for the establishment of OT-CEC systems. [ABSTRACT FROM AUTHOR]

The phenolics and flavonoids extraction is a well-studied strategy for food waste and biomass valorization, with little research on their downstream purification for commercial applications. This study presents a methodology for their purification using molecular imprinted polymers. [Display omitted] • In-silico guided design & polymer synthesis for purifying phenolic acids from food waste. • Bio-based polymer provides the highest reported separation factor for chlorogenic acid. • Demonstration of the polymer's reusability, versatility, and efficacy. • Application of the polymer on two food waste feedstocks. • Evaluation of economic and commercial advantages of the proposed methodology. Food waste is a profound challenge as 17% of global food production (i.e., 931 million tons) ends up as waste yearly. A cost-effective strategy is the extraction of high-value phenolic acids from food waste, but their downstream purification is challenging owing to their similar chemical nature, high boiling points, and low concentrations in complex mixtures. Herein, we propose separating target phenolics using molecular imprinted polymers. The stability of the monomer-template complex during the synthesis is critical in optimizing the polymer selectivity and performance. COnductor like Screening MOdel for Real Solvents (COSMO-RS) and Hansen Solubility Parameters in Practice (HSPiP) computations were used to screen the interaction of 28 monomers and 13 porogenic solvents with chlorogenic acid as the target molecule. Experiments revealed that itaconic acid, the functional monomer, and tetrahydrofuran (THF), the synthesis solvent, provide the highest reported separation factor. The polymer exhibits superior selectivity towards chlorogenic acid in concentrated solutions of up to 1 mg/mL, and its high sensitivity to various functionalities enables the effective separation of all target phenolic acids. The polymer's performance was evaluated in different extraction solvents, and Fourier transform infrared (FTIR) studies revealed polymer–solvent interaction as the critical factor influencing its performance. The application of the polymer in purifying up to 92% chlorogenic acid from coffee beans and potato peel waste extractives is demonstrated, and its reusability is evaluated. In contrast to the current industrial purification methodology that produces mixtures, the proposed technology provides at least eleven times higher economic value and 95% less carbon emissions based on lab-scale techno-economic analysis. [ABSTRACT FROM AUTHOR]

• Efficient removal strategies for microplastics are lacking. • Magnetic-seeded filtration showed high separation efficiencies (∼95%) for dilute suspensions. • Electrostatic interactions between particles were shown to be process-determining. • A parameter study identified relevant process variables and yielded clear application guidelines. • The measurement of agglomeration kinetics enables further optimization. Microplastics have become a highly discussed topic: Whether through the decomposition of larger plastic waste or direct usage on a small particle scale, microplastics find their way into the natural ecosystem with uncertain consequences: In particular, the ingestion and therefore the introduction of these particles into the food web (often carrying adsorbed chemicals) poses still not fully understood hazards for mankind. This work focuses on the separation of such particles from aquatic suspensions and evaluates the viability of magnetic seeded filtration in this field. In this study it could be shown that it is generally possible to separate fine polymeric particles from dilute suspensions in a highly effective manner. A broad range of process conditions were investigated with separation efficiencies reaching up to 95 %. The pH and ultimately the surface charge of the particles were identified to be the crucial process relevant parameters. More exactly, the surface potentials should be either small or oppositely charged leading to a diminishing or even attractive electrostatic interaction. However, when both agglomeration partners exhibit an electrostatic repulsion, a thorough parameter optimization nevertheless yielded high separation efficiencies. In particular, the ionic strength and magnetic seed concentration proved to be determining factors in this case. Lastly, the process kinetics were investigated and a limited exponential growth character was observed which could be modeled with basic equations from agglomeration theory under simplifying assumptions. This knowledge further assists the selection of an optimal parameter set for a process engineering application. [ABSTRACT FROM AUTHOR]

A facile method to improve CO 2 separation performance of polymer is to incorporate CO 2 -philic particles. In this study, sulfonated polymer brush functionalized graphene oxide nanosheets (S-GO) as fillers, with sulfonated polymer brush as CO 2 -philic chain anchored on GO were introduced into SPEEK membrane at nanoscale level to enhance CO 2 selectivity of the membrane. The S-GO enhanced the interface compatibility as shown by SEM, and the "sieve-in-a-cage" morphology in MMMs disappeared by the introduction of CO 2 -philic polymer brush. Benefiting from the introduction of brush at the interface, on one hand, the CO 2 -philic brush on S-GO helped to widen CO 2 transport pathways verified by the increased radius of free volume cavity (r 3) and the fractional free volume (FFV), which resulted in the increase in gas permeability. On the other hand, the addition of the polymer brush on GO increased CO 2 -philic sites, which imparted enhancement in the CO 2 solubility selectivity. Besides, the transport of gases through the GO nanosheets created the increment in CO 2 diffusion selectivity. SPEEK/S-GO MMMs showed pronounced enhancements in both CO 2 permeability and CO 2 /CH 4 (N 2) selectivity. Specifically, for the SPEEK/S-GO membrane doped with 8 wt% S-GO nanosheets, the CO 2 permeability reached 1327 Barrer, and CO 2 /CH 4 selectivity increased by 179% in comparison with the SPEEK control membrane, surpassing the 2008 Robeson upper bound. The distinctive virtues of polymer brush functionalized filler may be extended to fabricate a series of MMMs for efficient molecule separation. Image 1 • CO 2 -philic polymer brush functionalized graphene oxide nanosheets were prepared. • CO 2 -philic polymer brush functionalized GO was incorporated to fabricate MMMs. • Interface compatibility of MMMs was enhanced by addition of CO 2 -philic brush. • CO 2 transport pathways were widened due to the presence of CO 2 -philic brush. • Gas separation performance of MMMs surpassed Robeson upper bound in 2008. [ABSTRACT FROM AUTHOR]

A new method for the molecular weight (MW) determination of chitosans by asymmetric flow field flow fractionation (AF-FFF or AF4) coupled with multi-angle light scattering (MALS) and differential refractive index (RI) detectors is proposed. The method allows the separation of polymer from molecular aggregates typically found in chitosan solutions making possible the accurate determination of MW distribution of the polymer. The effect of different experimental conditions on the obtained results has been evaluated and compared with those obtained from SEC-MALS-RI (size exclusion chromatography-MALS-RI). The chitosans analysed were from different biological sources and of varying degree of acetylation. AF4-MALS-RI results revealed that although aggregates are minimised when using a good solvent, a fraction still remains, and it is only completely eliminated by filtration through small pore sizes (≤0.45 μm). This represents a limitation for the characterisation of high MW chitosan, where filtration can lead to considerable sample loss in the filter. The method described here has the advantage of not only allowing the identification and separation of the aggregates present, but also the accurate determination of the MW distribution for a wide range of chitosans of varying type where results are well correlated with those obtained by more conventional techniques. [ABSTRACT FROM AUTHOR]

• Persulfate combined wet air oxidation (PWAO) is proposed to deep remove benzothiazole. • OH is firstly detected by electron paramagnetic resonance in wet air oxidation process. • OH plays a very important role in the PWAO process. • High COD removal is achieved with a large amount of microsphere polymers recycling. • The PWAO process has a lower operating cost than WAO in COD removal. Wet air oxidation (WAO) has an obvious advantage in treating wastewater with high concentration of organics, but harsh reaction conditions are required and the treatment efficiency has not reached a satisfactory level. Herein, we developed a low dosage of persulfate promoted WAO process (PWAO) to remove a model heterocyclic pollutant benzothiazole (BTH). The addition of persulfate remarkably enhanced the elimination of benzothiazole (BTH) and COD from water via degradation and polymerization. Under optimized operation condition (with 11.1 mM K 2 S 2 O 8 addition into WAO), about 65.0% of BTH converted into microsphere polymers and more than 94.6% COD was eliminated from water after polymers separation. Electron paramagnetic resonance (EPR) analysis and quenching experiments revealed that OH was effectively generated in a wide range of reaction temperature and it played the key role in BTH degradation and polymerization, while SO 4 − was detected at low temperature for its fast decomposition at high temperature. Quantum chemical calculation together with ultra-performance liquid chromatography with electrospray ionization tandem mass spectrometry (UPLC-ESI-MS) analysis confirmed that the degradation and polymerization of BTH mainly started from the heterocyclic ring, followed by further oxidation or polymerization. Comparing with normal WAO process, the PWAO technology had an advantage in lower operating cost in removing per unit COD and carbon resource recycle, which indicates a promising prospect in treating wastewater with high concentration of heterocyclic compounds. [ABSTRACT FROM AUTHOR]