Journal articles: 'Porous Polymers'

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Wu, Cai-Ying, and Walter A. Aue. "Protected porous polymers." Canadian Journal of Chemistry 67, no. 3 (March 1, 1989): 389–401. http://dx.doi.org/10.1139/v89-062.

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This study was designed to answer the question whether the chromatographic performance of porous polymers — serving here as a model system for pressure-sensitive separation media of relatively large mass transfer resistance — could be improved (a) by imposing on them a chromatographically favorable, extrinsic macrostructure and (b) by protecting that macrostructure against physical deformation. Packed-column gas chromatography was used as the test system.Protected porous polymers (PPP's) were synthesized from pure divinylbenzene (DVB) inside conventional diatomaceous supports, using various amounts and types of porogens. The non-extractable polymer loads ranged from 10 to 40% and conformed to (i.e. formed layers on) the diatomaceous macrostructures. The best plate numbers were in excess of 4000/m on a 100/120 mesh Chromosorb W base. The mass transfer resistance of these materials was very low and permitted high flow rates. The PPP's could be used up to 280 °C and did not appear to suffer deformation; in fact, the polymer appeared to shield the diatom supports from abrasion. The data indicate that the porous polymer deposits had relatively high specific surface areas, and produced a relatively large value for the free energy of sorption per methylene group, as compared with conventional porous polymer beads. Otherwise, protected and unprotected types of porous polymers had similar chromatographic characteristics. Keywords: porous polymer, poly(divinylbenzene), gas chromatography, protected polymer, diatoms.

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Wang, Hui, Genyuan Wang, Liang Hu, Bingcheng Ge, Xiaoliang Yu, and Jiaojiao Deng. "Porous Polymer Materials for CO2 Capture and Electrocatalytic Reduction." Materials 16, no. 4 (February 15, 2023): 1630. http://dx.doi.org/10.3390/ma16041630.

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Efficient capture of CO2 and its conversion into other high value-added compounds by electrochemical methods is an effective way to reduce excess CO2 in the atmosphere. Porous polymeric materials hold great promise for selective adsorption and electrocatalytic reduction of CO2 due to their high specific surface area, tunable porosity, structural diversity, and chemical stability. Here, we review recent research advances in this field, including design of porous organic polymers (POPs), porous coordination polymers (PCPs), covalent organic frameworks (COFs), and functional nitrogen-containing polymers for capture and electrocatalytic reduction of CO2. In addition, key issues and prospects for the optimal design of porous polymers for future development are elucidated. This review is expected to shed new light on the development of advanced porous polymer electrocatalysts for efficient CO2 reduction.

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Naga, Naofumi, Minako Ito, Aya Mezaki, Hao-Chun Tang, Tso-Fu Mark Chang, Masato Sone, Hassan Nageh, and Tamaki Nakano. "Morphology Control and Metallization of Porous Polymers Synthesized by Michael Addition Reactions of a Multi-Functional Acrylamide with a Diamine." Materials 14, no. 4 (February 9, 2021): 800. http://dx.doi.org/10.3390/ma14040800.

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Porous polymers have been synthesized by an aza-Michael addition reaction of a multi-functional acrylamide, N,N′,N″,N‴-tetraacryloyltriethylenetetramine (AM4), and hexamethylene diamine (HDA) in H2O without catalyst. Reaction conditions, such as monomer concentration and reaction temperature, affected the morphology of the resulting porous structures. Connected spheres, co-continuous monolithic structures and/or isolated holes were observed on the surface of the porous polymers. These structures were formed by polymerization-induced phase separation via spinodal decomposition or highly internal phase separation. The obtained porous polymers were soft and flexible and not breakable by compression. The porous polymers adsorbed various solvents. An AM4-HDA porous polymer could be plated by Ni using an electroless plating process via catalyzation by palladium (II) acetylacetonate following reduction of Ni ions in a plating solution. The intermediate Pd-catalyzed porous polymer promoted the Suzuki-Miyaura cross coupling reaction of 4-bromoanisole and phenylboronic acid.

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Berro, Soumaya, Ranim El Ahdab, Houssein Hajj Hassan, Hassan M. Khachfe, and Mohamad Hajj-Hassan. "From Plastic to Silicone: The Novelties in Porous Polymer Fabrications." Journal of Nanomaterials 2015 (2015): 1–21. http://dx.doi.org/10.1155/2015/142195.

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Porous polymers are gaining increased interest in several areas due, in great part, to their large surface area and unique physiochemical properties. Porous polymers are conventionally manufactured using specific processes related to the chemical structure of each polymer. With the wide variety of porous polymers that have been designed, fabricated, and tested to date, this review aims to provide an overview of the advances and recent progress in the preparation processes and fabrication techniques. A detailed comparison between these techniques is also provided. Some of these techniques offer the advantage of controlling the porosity and the possibility to obtain porous 3D polymers. A new generic fabrication process that can be applied to all liquid polymers to texture their outer surfaces with a desired porosity is also presented. The proposed process, which is based on two micromolding steps, offers flexibility in terms of tailoring the texture of the final polymer by simply using porous silicon templates with different pore sizes and configurations. The anticipated process was successfully implemented to texture polyethyl hydrosiloxane (PMHS) using porous silicon and polymethyl methacrylate (PMMA) scaffolds.

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Zhang, Huacheng, Jie Han, and Chao Li. "Pillararene-based conjugated porous polymers." Polymer Chemistry 12, no. 19 (2021): 2808–24. http://dx.doi.org/10.1039/d1py00238d.

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Mirzaie Yegane, Mohsen, Pouyan E. Boukany, and Pacelli Zitha. "Fundamentals and Recent Progress in the Flow of Water-Soluble Polymers in Porous Media for Enhanced Oil Recovery." Energies 15, no. 22 (November 16, 2022): 8575. http://dx.doi.org/10.3390/en15228575.

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Due to increased energy demand, it is vital to enhance the recovery from existing oilfields. Polymer flooding is the most frequently used chemical enhanced oil recovery (cEOR) method in field applications that increases the oil sweep and displacement efficiencies. In recent years, there has been growing interest to assess the use of polymer flooding in an increasing number of field applications. This is due to the improved properties of polymers at high-salinity and high-temperature conditions and an increased understanding of the transport mechanisms of water-soluble polymers in porous media. In this review, we present an overview of the latest research into the application of polymers for cEOR, including mechanisms of oil recovery improvement and transport mechanisms in porous media. We focus on the recent advances that have been made to develop polymers that are suitable for high-salinity and high-temperature conditions and shed light on new insights into the flow of water-soluble polymers in porous media. We observed that the viscoelastic behavior of polymers in porous media (e.g., shear thickening and elastic turbulence) is the most recently debated polymer flow mechanism in cEOR applications. Moreover, advanced water-soluble polymers, including hydrophobically modified polymers and salt- and temperature-tolerant modified polyacrylamides, have shown promising results at high-salinity and high-temperature conditions.

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Tan and Rodrigue. "A Review on Porous Polymeric Membrane Preparation. Part II: Production Techniques with Polyethylene, Polydimethylsiloxane, Polypropylene, Polyimide, and Polytetrafluoroethylene." Polymers 11, no. 8 (August 5, 2019): 1310. http://dx.doi.org/10.3390/polym11081310.

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The development of porous polymeric membranes is an important area of application in separation technology. This article summarizes the development of porous polymers from the perspectives of materials and methods for membrane production. Polymers such as polyethylene, polydimethylsiloxane, polypropylene, polyimide, and polytetrafluoroethylene are reviewed due to their outstanding thermal stability, chemical resistance, mechanical strength, and low cost. Six different methods for membrane fabrication are critically reviewed, including thermally induced phase separation, melt-spinning and cold-stretching, phase separation micromolding, imprinting/soft molding, manual punching, and three-dimensional printing. Each method is described in details related to the strategy used to produce the porous polymeric membranes with a specific morphology and separation performances. The key factors associated with each method are presented, including solvent/non-solvent system type and composition, polymer solution composition and concentration, processing parameters, and ambient conditions. Current challenges are also described, leading to future development and innovation to improve these membranes in terms of materials, fabrication equipment, and possible modifications.

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Gawdzik, B., and M. Maciejewska. "Studies on the Selectivity of Porous Methacrylate Polymers." Adsorption Science & Technology 20, no. 5 (June 2002): 523–30. http://dx.doi.org/10.1260/026361702320644806.

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Four types of porous methacrylate polymers were synthesized as stationary phases for gas chromatography. The influence of the chemical structure of the monomers used in the synthesis on the selectivities of the resulting polymers was studied. Two procedures were applied to determine the selectivities of the copolymers: the selectivity triangle and the general selectivity. Porapak Q, the least polar commercially available porous polymer, was used as a reference phase.

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Silverstein, Michael S. "Special Issue of Polymer on porous polymers." Polymer 55, no. 1 (January 2014): 302–3. http://dx.doi.org/10.1016/j.polymer.2013.11.008.

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Morones-Ramírez, J. Rubén. "Coupling Metallic Nanostructures to Thermally Responsive Polymers Allows the Development of Intelligent Responsive Membranes." International Journal of Polymer Science 2014 (2014): 1–7. http://dx.doi.org/10.1155/2014/967615.

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Development of porous membranes capable of controlling flow or changing their permeability to specific chemical entities, in response to small changes in environmental stimuli, is an area of appealing research, since these membranes present a wide variety of applications. The synthesis of these membranes has been mainly approached through grafting of environmentally responsive polymers to the surface walls of polymeric porous membranes. This synergizes the chemical stability and mechanical strength of the polymer membrane with the fast response times of the bonded polymer chains. Therefore, different composite membranes capable of changing their effective pore size with environmental triggers have been developed. A recent interest has been the development of porous membranes responsive to light, since these can achieve rapid, remote, noninvasive, and localized flow control. This work describes the synthesis pathway to construct intelligent optothermally responsive membranes. The method followed involved the grafting of optothermally responsive polymer-metal nanoparticle nanocomposites to polycarbonate track-etched porous membranes (PCTEPMs). The nanoparticles coupled to the polymer grafts serve as the optothermal energy converters to achieve optical switching of the pores. The results of the paper show that grafting of the polymer andin situsynthesis of the metallic particles can be easily achieved. In addition, the composite membranes allow fast and reversible switching of the pores using both light and heat permitting control of fluid flow.

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Chernyshev, Leonid I., Oleg N. Balitskii, Nataliya E. Fedorova, Olga I. Get'man, and Valerii M. Yur'ev. "Porous Permeable Polymers." Powder Metallurgy and Metal Ceramics 43, no. 3/4 (March 2004): 143–49. http://dx.doi.org/10.1023/b:pmmc.0000035702.20726.53.

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Gurr, Paul A., Zhou Zhang, Xiaojuan Hao, Timothy C. Hughes, and Greg G. Qiao. "Highly Ordered Honeycomb Film Formation of Linear Polymers by the Breath Figure Technique." Australian Journal of Chemistry 69, no. 10 (2016): 1130. http://dx.doi.org/10.1071/ch16119.

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Highly ordered, porous honeycomb (HC) films were prepared by the breath figure technique from linear polymers poly(methyl methacrylate) (PMMA) and polystyrene (PS). Typically HC films are difficult to form from such simple linear polymers. The addition of a novel fluorinated polymer (FP) additive with as little as 1 wt-% to PMMA or 5 wt-% to PS was required to obtain regular porous HC films. Through investigation of the influence of the additive on the polymer properties, three parameters based on interfacial tension, polymer solution viscosity, and polymer solidification rate were identified as key factors affecting the ability of polymer systems to form regular porous HC films. A new hypothesis was subsequently developed based on the relationships of these parameters to explain the unusual behaviour associated with HC film formation from linear PMMA and PS with addition of FP additive. This work will provide a new tool to guide the formation of HC films and will greatly broaden the range of polymers used to form HC films in the future.

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Al-Shakry, Badar, Tormod Skauge, Behruz Shaker Shiran, and Arne Skauge. "Polymer Injectivity: Investigation of Mechanical Degradation of Enhanced Oil Recovery Polymers Using In-Situ Rheology." Energies 12, no. 1 (December 24, 2018): 49. http://dx.doi.org/10.3390/en12010049.

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Water soluble polymers have attracted increasing interest in enhanced oil recovery (EOR) processes, especially polymer flooding. Despite the fact that the flow of polymer in porous medium has been a research subject for many decades with numerous publications, there are still some research areas that need progress. The prediction of polymer injectivity remains elusive. Polymers with similar shear viscosity might have different in-situ rheological behaviors and may be exposed to different degrees of mechanical degradation. Hence, determining polymer in-situ rheological behavior is of great significance for defining its utility. In this study, an investigation of rheological properties and mechanical degradation of different partially hydrolyzed polyacrylamide (HPAM) polymers was performed using Bentheimer sandstone outcrop cores. The results show that HPAM in-situ rheology is different from bulk rheology measured by a rheometer. Specifically, shear thickening behavior occurs at high rates, and near-Newtonian behavior is measured at low rates in porous media. This deviates strongly from the rheometer measurements. Polymer molecular weight and concentration influence its viscoelasticity and subsequently its flow characteristics in porous media. Exposure to mechanical degradation by flow at high rate through porous media leads to significant reduction in shear thickening and thereby improved injectivity. More importantly, the degraded polymer maintained in-situ viscosity at low flow rates indicating that improved injectivity can be achieved without compromising viscosity at reservoir flow rates. This is explained by a reduction in viscoelasticity. Mechanical degradation also leads to reduced residual resistance factor (RRF), especially for high polymer concentrations. For some of the polymer injections, successive degradation (increased degradation with transport length in porous media) was observed. The results presented here may be used to optimize polymer injectivity.

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Jadhav, Sushilkumar A., and Dominique Scalarone. "Thermoresponsive Polymer Grafted Porous Silicas as Smart Nanocarriers." Australian Journal of Chemistry 71, no. 7 (2018): 477. http://dx.doi.org/10.1071/ch18229.

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Porous silica particles grafted with various stimuli-responsive polymers are investigated with great interest for their use as smart pharmaceutical nanocarriers in advanced drug delivery systems (DDS). In particular, porous silica particles grafted with thermoresponsive polymers that exhibit thermally triggered on/off gating mechanisms have shown improved performance as hybrid DDS capable of controlling the release of different drugs in various mediums which resemble complex biological environments. In addition, the tuning of the drug release profiles as per requirements has proved possible with modifications to the porous core and the grafted thermoresponsive polymers. This highlight presents a brief discussion of basic preparation techniques and some recent significant developments in the field of thermoresponsive polymer grafted porous silica particles as smart pharmaceutical nanocarriers.

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Seright, Randall S., J. Mac Seheult, and Todd Talashek. "Injectivity Characteristics of EOR Polymers." SPE Reservoir Evaluation & Engineering 12, no. 05 (October 27, 2009): 783–92. http://dx.doi.org/10.2118/115142-pa.

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Summary For applications in which enhanced-oil-recovery (EOR) polymer solutions are injected, we estimate injectivity losses (relative to water injectivity) if fractures are not open. We also consider the degree of fracture extension that may occur if fractures are open. Three principal EOR polymer properties are examined that affect injectivity:debris in the polymer,polymer rheology in porous media, andpolymer mechanical degradation. An improved test was developed to measure the tendency of EOR polymers to plug porous media. The new test demonstrated that plugging tendencies varied considerably among both partially hydrolyzed polyacrylamide (HPAM) and xanthan polymers. Rheology and mechanical degradation in porous media were quantified for a xanthan and an HPAM polymer. Consistent with previous work, we confirmed that xanthan solutions show pseudoplastic behavior in porous rock that closely parallels that in a viscometer. Xanthan was remarkably resistant to mechanical degradation, with a 0.1% xanthan solution (in seawater) experiencing only a 19% viscosity loss after flow through 102-md Berea sandstone at a pressure gradient of 24,600 psi/ft. For 0.1% HPAM in both 0.3% NaCl brine and seawater in 573-md Berea sandstone, Newtonian behavior was observed at low to moderate fluid fluxes, while pseudodilatant behavior was seen at moderate to high fluxes. No evidence of pseudoplastic behavior was seen in the porous rock, even though one solution exhibited a power-law index of 0.64 in a viscometer. For this HPAM in both brines, the onset of mechanical degradation occurred at a flux of 14 ft/d in 573-md Berea. Considering the polymer solutions investigated, satisfactory injection of more than 0.1 pore volume (PV) in field applications could only be expected for the cleanest polymers (i.e., that do not plug before 1,000 cm3/cm2 throughput), without inducing fractures (or formation parts for unconsolidated sands). Even in the absence of face plugging, the viscous nature of the solutions investigated requires that injectivity must be less than one-fifth that of water if formation parting is to be avoided (unless the injectant reduces the residual oil saturation and substantially increases the relative permeability to water). Since injectivity reductions of this magnitude are often economically unacceptable, fractures or fracture-like features are expected to open and extend significantly during the course of most polymer floods. Thus, an understanding of the orientation and growth of fractures may be crucial for EOR projects in which polymer solutions are injected. Introduction Maintaining mobility control is essential during chemical floods (polymer, surfactant, alkaline floods). Consequently, viscosification using water soluble polymers is usually needed during chemical EOR projects. Unfortunately, increased injectant viscosity could substantially reduce injectivity, slow fluid throughput, and delay oil production from flooded patterns. The objectives of this paper are to estimate injectivity losses associated with injection of polymer solutions if fractures are not open and to estimate the degree of fracture extension if fractures are open. We examine the three principal EOR polymer properties that affect injectivity:debris in the polymer,polymer rheology in porous media, andpolymer mechanical degradation. Although some reports suggest that polymer solutions can reduce the residual oil saturation below values expected for extensive waterflooding (and thereby increase the relative permeability to water), this effect is beyond the scope of this paper.

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Rijal, Girdhari, Chandra Bathula, and Weimin Li. "Application of Synthetic Polymeric Scaffolds in Breast Cancer 3D Tissue Cultures and Animal Tumor Models." International Journal of Biomaterials 2017 (2017): 1–9. http://dx.doi.org/10.1155/2017/8074890.

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Preparation of three-dimensional (3D) porous scaffolds from synthetic polymers is a challenge to most laboratories conducting biomedical research. Here, we present a handy and cost-effective method to fabricate polymeric hydrogel and porous scaffolds using poly(lactic-co-glycolic) acid (PLGA) or polycaprolactone (PCL). Breast cancer cells grown on 3D polymeric scaffolds exhibited distinct survival, morphology, and proliferation compared to those on 2D polymeric surfaces. Mammary epithelial cells cultured on PLGA- or PCL-coated slides expressed extracellular matrix (ECM) proteins and their receptors. Estrogen receptor- (ER-) positive T47D breast cancer cells are less sensitive to 4-hydroxytamoxifen (4-HT) treatment when cultured on the 3D porous scaffolds than in 2D cultures. Finally, cancer cell-laden polymeric scaffolds support consistent tumor formation in animals and biomarker expression as seen in human native tumors. Our data suggest that the porous synthetic polymer scaffolds satisfy the basic requirements for 3D tissue cultures both in vitro and in vivo. The scaffolding technology has appealing potentials to be applied in anticancer drug screening for a better control of the progression of human cancers.

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Yudin, Vladimir V., Margarita P. Shurygina, Marfa N. Egorikhina, Diana Ya Aleynik, Daria D. Linkova, Irina N. Charykova, Roman S. Kovylin, and Sergey A. Chesnokov. "Pore Structure Tuning of Poly-EGDMA Biomedical Material by Varying the O-Quinone Photoinitiator." Polymers 15, no. 11 (June 2, 2023): 2558. http://dx.doi.org/10.3390/polym15112558.

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Porous polymer monoliths with thicknesses of 2 and 4 mm were obtained via polymerization of ethylene glycol dimethacrylate (EGDMA) under the influence visible-light irradiation in the presence of a 70 wt% 1-butanol porogenic agent and o-quinone photoinitiators. The o-quinones used were: 3,5-di-tret-butyl-benzoquinone-1,2 (35Q), 3,6-di-tret-butyl-benzoquinone-1,2 (36Q), camphorquinone (CQ), and 9,10-phenanthrenequinone (PQ). Porous monoliths were also synthesized from the same mixture but using 2,2′-azo-bis(iso-butyronitrile) (AIBN) at 100 °C instead o-quinones. According to the results of scanning electron microscopy, all the resulting samples were conglomerates of spherical, polymeric particles with pores between them. Use of mercury porometry showed that the interconnected pore systems of all the polymers were open. The average pore size, Dmod, in such polymers strongly depended on both the nature of the initiator and the method of initiation of polymerization. For polymers obtained in the presence of AIBN, the Dmod value was as low as 0.8 μm. For polymers obtained via photoinitiation in the presence of 36Q, 35Q, CQ, and PQ, the Dmod values were significantly greater, i.e., 9.9, 6.4, 3.6, and 3.7 μm, respectively. The compressive strength and Young’s modulus of the porous monoliths increased symbatically in the series PQ < CQ < 36Q < 35Q < AIBN with decreasing proportions of large pores (over 12 μm) in their polymer structures. The photopolymerization rate of the EGDMA and 1-butanol, 30:70 wt% mixture was maximal for PQ and minimal for 35Q. All polymers tested were non-cytotoxic. Based on the data from MTT testing, it can be noted that the polymers obtained via photoinitiation were characterized by their positive effect on the proliferative activity of human dermal fibroblasts. This makes them promising osteoplastic materials for clinical trials.

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Al-Ithawi, Wahab K. A., Albert F. Khasanov, Igor S. Kovalev, Igor L. Nikonov, Vadim A. Platonov, Dmitry S. Kopchuk, Sougata Santra, Grigory V. Zyryanov, and Brindaban C. Ranu. "TM-Free and TM-Catalyzed Mechanosynthesis of Functional Polymers." Polymers 15, no. 8 (April 12, 2023): 1853. http://dx.doi.org/10.3390/polym15081853.

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Mechanochemically induced methods are commonly used for the depolymerization of polymers, including plastic and agricultural wastes. So far, these methods have rarely been used for polymer synthesis. Compared to conventional polymerization in solutions, mechanochemical polymerization offers numerous advantages such as less or no solvent consumption, the accessibility of novel structures, the inclusion of co-polymers and post-modified polymers, and, most importantly, the avoidance of problems posed by low monomer/oligomer solubility and fast precipitation during polymerization. Consequently, the development of new functional polymers and materials, including those based on mechanochemically synthesized polymers, has drawn much interest, particularly from the perspective of green chemistry. In this review, we tried to highlight the most representative examples of transition-metal (TM)-free and TM-catalyzed mechanosynthesis of some functional polymers, such as semiconductive polymers, porous polymeric materials, sensory materials, materials for photovoltaics, etc.

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Silverstein, Michael S. "Second special issue of Polymer on porous polymers." Polymer 126 (September 2017): 259–60. http://dx.doi.org/10.1016/j.polymer.2017.08.062.

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Shi, Leiting, Shijie Zhu, Zhongbin Ye, Jian Zhang, Xinsheng Xue, and Wensen Zhao. "The seepage flow characteristics of hydrophobically associated polymers with different aggregation behaviours in porous media." Royal Society Open Science 7, no. 1 (January 2020): 191270. http://dx.doi.org/10.1098/rsos.191270.

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The polymer solution for oil displacement is subjected to strong shear action in practical application, and this action will affect its percolation characteristics in porous media. The effects of mechanical shearing on the solution properties and seepage characteristics of modified hydrophobically associated polymers and dendrimers with two different aggregation behaviours were studied. The results showed that mechanical shearing did not affect hydrophobic microzones. Polymers can re-associate to restore part of the network structure, thereby improving shear resistance (dendritic hydrophobically associating polymers > hydrophobically modified partially hydrolysed polyacrylamide). Polymers with ‘cluster’ aggregation behaviour enhanced solution performance, enabling them to establish higher resistance coefficient (RF) and residual resistance factor (RRF) in porous media but also bringing about injection difficulties. Increasing the injection rate would increase the injection pressure, but the established RF and RRF showed a downward trend. Mechanical shear pretreatment effectively improved the injectability of the polymer. To achieve polymer injection and flow control, pre-shearing polymer solution and low-speed injection can be used in field applications.

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An, Changwei, Jun Zhang, and Xianqi Guan. "CO₂ Adsorption Based on Porphyrin Based Porous Organic Polymers." Journal of Physics: Conference Series 2463, no. 1 (March 1, 2023): 012057. http://dx.doi.org/10.1088/1742-6596/2463/1/012057.

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Abstract In order to efficiently catalyze the cycloaddition reaction of CO2 and epoxy alkanes under mild environment and no catalyst, this paper designed and synthesized two kinds of porphyrin based porous organic polymers—porphyrin based porous organic polymer containing carboxyl group (ppop-cooh) and porphyrin based porous organic polymer containing quaternary ammonium salt ion pair. Quaternary ammonium salt cation anion pair nucleophilic groups and metal active centers were introduced into the polymer by pre- and post-modification respectively. The chemical structure and pore structure of the polymer were characterized by infrared spectroscopy and physical adsorption instrument, and its effect as a catalyst on the cycloaddition reaction of CO2 and epoxy alkanes was studied. From the results, it is demonstrated that the two polymers had a multistage pore structure with a specific surface area of 302 m2/g-514 m2/g. The synergistic effect of Lewis acid metal ions, nucleophiles and multistage pore structure in the polymer significantly promotes the cycloaddition reaction between CO2 and epoxy alkanes. Under mild conditions (80°C, 0.3 MPa, 24h), the selectivity and conversion of the reaction reach more than 99%. The polymer is repeated for many times. After use, it still has good catalytic performance.

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Kovylin, R. S., D. Ya Aleynik, and I. L. Fedushkin. "Modern Porous Polymer Implants: Synthesis, Properties, and Application." Polymer Science, Series C 63, no. 1 (January 2021): 29–46. http://dx.doi.org/10.1134/s1811238221010033.

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Abstract The needs of modern surgery triggered the intensive development of transplantology, medical materials science, and tissue engineering. These directions require the use of innovative materials, among which porous polymers occupy one of the leading positions. The use of natural and synthetic polymers makes it possible to adjust the structure and combination of properties of a material to its particular application. This review generalizes and systematizes the results of recent studies describing requirements imposed on the structure and properties of synthetic (or artificial) porous polymer materials and implants on their basis and the advantages and limitations of synthesis methods. The most extensively employed, promising initial materials are considered, and the possible areas of application of polymer implants based on these materials are highlighted.

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Turani-i-Belloto, Alexandre, Thomas Brunet, Alexandre Khaldi, and Jacques Leng. "A Sacrificial Route for Soft Porous Polymers Synthesized via Frontal Photo-Polymerization." Polymers 12, no. 5 (April 27, 2020): 1008. http://dx.doi.org/10.3390/polym12051008.

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Within the very large range of porous polymers and a related immense scope of applications, we investigate here a specific route to design soft porous polymers with controlled porosity: we use aqueous-based formulations of oligomers with mineral particles which are solidified into a hydrogel upon photo-polymerization; the embedded particles are then chemically etched and the hydrogel is dried to end up with a soft porous polymeric scaffold with micron-scale porosity. Morphological and physical features of the porous polymers are measured and we demonstrate that the porosity of the final material is primarily determined by the amount of initially dispersed sacrificial particles. In addition, the liquid formulations we use to start with are convenient for a variety of material forming techniques such as microfluidics, embossing, etc., which lead to many different morphologies (monoliths, spherical particles, patterned substrates) based on the same initial material.

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Lee, Suk Joong, and Jong Ho Yoon. "Use of Porphyrin Containing Porous Materials in Heterogeneous Catalyst." ECS Meeting Abstracts MA2022-01, no. 14 (July 7, 2022): 957. http://dx.doi.org/10.1149/ma2022-0114957mtgabs.

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Due to their potential applications in catalysis, separation, gas storage, drug delivery, and biosensing, porous materials (PMs) such as porous organic polymers (POPs), polymers with intrinsic microporosity (PIMs), porous coordination polymers (PCPs), and metal–organic frameworks (MOFs), have received much attention. Various building blocks have been prepared and demonstrated various functional materials. Among the various organic building blocks, porphyrin has become one of the most important building blocks for the construction of such materials witnessed by a wide range of molecular architectures using porphyrin derivatives with various applications. Mn(III)- and Fe(III)-containing metalloporphyrins are often used to fabricate various functional molecular architectures and to mimic the extraordinary behavior of enzymes in both homogeneous and heterogeneous catalytic systems. In the case of homogeneous catalysis, Mn(III)- and Fe(III)-containing metalloporphyrins have frequent trouble with fast catalytic degradation because of µ-oxo dimer formation or ligand oxidation. To avoid the catalyst degradation, the immobilization and/or site-isolation of homogeneous catalysts using supporters such as polymers, membranes, and MOFs, are widely used strategy. In addition, they are often used to modify the surface of porous silica materials such as SBA-15, MCM-41 and MCM-48, because these porous silica materials exhibit narrow pore size distributions, high thermal stability and easy accessibility. In this presentation, we like to show the use of metalloporphyrins in various porous materials and their use as heterogeneous catalysts. References D. Y. Shin, J. H. Yoon, S. H. Kim, H. Baik, S. J. Lee,* "Immobilization of Porphyrinic Mn(III) Catalyst on a New Class of Silica Support Comprising Three-Dimensionally Interconnected Network with Two Different Sizes of Pores", Catal. Sci. Technol. 2018, 8, 6306-6310. J. Yi, H. Y. Jeong, D. Y. Shin, C. Kim, S. J. Lee,* "Mn(III)-Porphyrin Containing Heterogeneous Catalyst based on Microporous Polymeric Constituents as a New Class of Catalyst Support", ChemCatChem 2018, 10, 3974-3977. J. Yoon, H. M. Choi, S. J. Lee,* "Cu(II)Cl2 containing bispyridine-based porous organic polymer support prepared via alkyne–azide cycloaddition as a heterogeneous catalyst for oxidation of various olefins", New J. Chem. 2020, 44, 9149-9152. H. M. Choi, Y. J. Kim, E. T. Choi, S. J. Lee,* "Selective Photocatalytic Oxidative Detoxification of a Chemical Warfare Agent Simulant by Porphyrin-Containing Polymers of Intrinsic Microporocity." ACS Appl. Polym. Mater.2021, submitted .

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Chen, Dongyang, Cheng Liu, Juntao Tang, Linfeng Luo, and Guipeng Yu. "Fluorescent porous organic polymers." Polymer Chemistry 10, no. 10 (2019): 1168–81. http://dx.doi.org/10.1039/c8py01620h.

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Bradley, David. "Mighty morphological porous polymers." Materials Today 17, no. 10 (December 2014): 476–77. http://dx.doi.org/10.1016/j.mattod.2014.10.026.

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Das, Saikat, Teng Ben, and Shilun Qiu. "Shaping of porous polymers." Polymer 207 (October 2020): 122928. http://dx.doi.org/10.1016/j.polymer.2020.122928.

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Hearon, Keith, Pooja Singhal, John Horn, Ward Small, Cory Olsovsky, Kristen C. Maitland, Thomas S. Wilson, and Duncan J. Maitland. "Porous Shape-Memory Polymers." Polymer Reviews 53, no. 1 (January 2013): 41–75. http://dx.doi.org/10.1080/15583724.2012.751399.

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Kitagawa, Susumu, Ryo Kitaura, and Shin-ichiro Noro. "Functional Porous Coordination Polymers." Angewandte Chemie International Edition 43, no. 18 (April 26, 2004): 2334–75. http://dx.doi.org/10.1002/anie.200300610.

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Fernando, Niranjala, Hugo Veldhuizen, Atsushi Nagai, Sybrand van der Zwaag, and Amor Abdelkader. "Layer-by-Layer Electrode Fabrication for Improved Performance of Porous Polyimide-Based Supercapacitors." Materials 15, no. 1 (December 21, 2021): 4. http://dx.doi.org/10.3390/ma15010004.

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Nanoporous polymers are becoming increasingly interesting materials for electrochemical applications, as their large surface areas with redox-active sites allow efficient adsorption and diffusion of ions. However, their limited electrical conductivity remains a major obstacle in practical applications. The conventional approach that alleviates this problem is the hybridisation of the polymer with carbon-based additives, but this directly prevents the utilisation of the maximum capacity of the polymers. Here, we report a layer-by-layer fabrication technique where we separated the active (porous polymer, top) layer and the conductive (carbon, bottom) layer and used these “layered” electrodes in a supercapacitor (SC). Through this approach, direct contact with the electrolyte and polymer material is greatly enhanced. With extensive electrochemical characterisation techniques, we show that the layered electrodes allowed a significant contribution of fast faradic surface reactions to the overall capacitance. The electrochemical performance of the layered-electrode SC outperformed other reported porous polymer-based devices with a specific gravimetric capacitance of 388 F·g−1 and an outstanding energy density of 65 Wh·kg−1 at a current density of 0.4 A·g−1. The device also showed outstanding cyclability with 90% of capacitance retention after 5000 cycles at 1.6 A·g−1, comparable to the reported porous polymer-based SCs. Thus, the introduction of a layered electrode structure would pave the way for more effective utilisation of porous organic polymers in future energy storage/harvesting and sensing devices by exploiting their nanoporous architecture and limiting the negative effects of the carbon/binder matrix.

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Cousins, Kimberley, and Renwu Zhang. "Highly Porous Organic Polymers for Hydrogen Fuel Storage." Polymers 11, no. 4 (April 16, 2019): 690. http://dx.doi.org/10.3390/polym11040690.

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Hydrogen (H2) is one of the best candidates to replace current petroleum energy resources due to its rich abundance and clean combustion. However, the storage of H2 presents a major challenge. There are two methods for storing H2 fuel, chemical and physical, both of which have some advantages and disadvantages. In physical storage, highly porous organic polymers are of particular interest, since they are low cost, easy to scale up, metal-free, and environmentally friendly. In this review, highly porous polymers for H2 fuel storage are examined from five perspectives: (a) brief comparison of H2 storage in highly porous polymers and other storage media; (b) theoretical considerations of the physical storage of H2 molecules in porous polymers; (c) H2 storage in different classes of highly porous organic polymers; (d) characterization of microporosity in these polymers; and (e) future developments for highly porous organic polymers for H2 fuel storage. These topics will provide an introductory overview of highly porous organic polymers in H2 fuel storage.

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Sapalidis, Andreas A. "Porous Polyvinyl Alcohol Membranes: Preparation Methods and Applications." Symmetry 12, no. 6 (June 5, 2020): 960. http://dx.doi.org/10.3390/sym12060960.

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Polymeric membrane technology is a constantly developing field in both the research and industrial sector, with many applications considered nowadays as mature such as desalination, wastewater treatment, and hemodialysis. A variety of polymers have been used for the development of porous membranes by implementing numerous approaches such as phase inversion, electrospinning, sintering, melt-spinning and cold-stretching, 3D printing, and others. Depending on the application, certain polymer characteristics such as solubility to non-toxic solvents, mechanical and thermal stability, non-toxicity, resistance to solvents, and separation capabilities are highly desired. Poly (vinyl alcohol) (PVA) is a polymer that combines the above-mentioned properties with great film forming capabilities, good chemical and mechanical stability, and tuned hydrophilicity, rendering it a prominent candidate for membrane preparation since the 1970s. Since then, great progress has been made both in preparation methods and possible unique applications. In this review, the main preparation methods and applications of porous PVA based membranes, along with introductory material are presented.

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Carpenter, Chris. "Study Reviews Recent Polymerflooding Advances in China." Journal of Petroleum Technology 74, no. 06 (June 1, 2022): 90–93. http://dx.doi.org/10.2118/0622-0090-jpt.

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This article, written by JPT Technology Editor Chris Carpenter, contains highlights of paper SPE 200084, “Recent Advances of Polymerflooding in China,” by Hu Guo and Kaoping Song, China University of Petroleum, and Yuming Wang, Daqing Oilfield Company, et al. The paper has not been peer reviewed. Polymerflooding is one of the more promising chemical enhanced oil recovery (EOR) techniques that features high incremental oil recovery factor, low cost, and wide reservoir applicability. This paper helps clarify ideas regarding polymerflooding implementation based on theory and practice in China. Introduction Laboratory studies aimed at increasing understanding of polymerflooding involve criteria for matching polymer with porous media, the polymer viscoelasticity effect on residual oil saturation (ROS), and displacement efficiency and synthesis of new polymers with better viscosifying capacity compared with typical partially hydrolyzed polyacrylamide (HPAM). The plugging of injectors in many oil fields is becoming increasingly common in many commercial blocks. This problem is especially serious for high-concentration polymer-injection blocks in fields such as Daqing, Xinjiang, and Henan. Understanding this phenomenon involves aligning the polymer and porous-media parameters such as permeability and pore size. Actual reservoir pressure distribution also must be considered. Because modern chemical EOR is based on ultralow interfacial tension (IFT) and minimum mobility ratio theory, the idea of combining the benefits of reducing IFT and increasing displacing-phase viscosity leads to a synthesis of amphiphilic polymers, which have features of both polymers and surfactants. This new type of polymer is sometimes called polymeric surfactant in China.

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Zhang, Huacheng. "Functional Polymeric Systems for Advanced Industrial Applications." Polymers 15, no. 5 (March 2, 2023): 1277. http://dx.doi.org/10.3390/polym15051277.

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Functional polymeric systems constitute a huge family of novel hierarchical architectures categorized by different polymeric shapes, such as linear, brush-like, star-like, dendrimer-like and network-like ones; various components, such as organic–inorganic hybrid oligomeric/polymeric materials and metal-ligated polymers; different features, such as porous polymers; and diverse approaching strategies and driving forces, such as conjugated/supramolecular/mechanical force-based polymers and self-assembled networks [...]

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Gorgol, Marek, Agnieszka Kierys, and Radosław Zaleski. "Positron Lifetime Annihilation Study of Porous Composites and Silicas Synthesized Using Polymer Templates." Defect and Diffusion Forum 373 (March 2017): 280–83. http://dx.doi.org/10.4028/www.scientific.net/ddf.373.280.

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The porous structure of polymer-silica composites, based on three polymer templates, which differ in a porosity and hydrophobicity, was examined using positron annihilation lifetime spectroscopy. Additionally, the investigation of silicas obtained after removal of polymers during calcination of composite materials, was performed. In composites based on hydrophobic polymers, silica condensates only in larger free volumes, while SiO2 deeply penetrates spaces between polymer chains, when the template is polar. Moreover, the structure of the silica gel, obtained after polymer removal, depends on chemical character of the template, rather than its porosity.

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Suwanprateeb, Jintamai. "Tissue Integrated 3D Printed Porous Polyethylene Implant." Key Engineering Materials 798 (April 2019): 65–70. http://dx.doi.org/10.4028/www.scientific.net/kem.798.65.

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Synthetic polymers are widely used in biomedical applications due to their advantages compared to other materials including low cost and ease of processability, good corrosion resistance and high properties to weight ratio. Among several polymeric biomaterials, polyethylene is a biocompatible polymer which has a long history of being utilized in many biomedical applications ranging from simple components to advanced implants. Although dense polyethylene is known to be a bioinert material which does not interact with host tissue, polyethylene in its appropriate porous form has been shown to be able to integrate well with surrounding host tissues and could widen its uses as bioactive implants. Porous polyethylene structure which was fabricated by three dimensional printing (3DP) is demonstrated. Its manufacturing technique, properties and clinical applications as tissue integrated implants which permitted soft or hard tissue ingrowth in tissue regeneration and replacement is discussed.

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Maji, Tapas Kumar, and Susumu Kitagawa. "Chemistry of porous coordination polymers." Pure and Applied Chemistry 79, no. 12 (January 1, 2007): 2155–77. http://dx.doi.org/10.1351/pac200779122155.

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Remarkable advances in the recent development of porous compounds based upon coordination polymers have paved the way toward functional chemistry having potential applications such as gas storage, separation, and catalysis. From the synthetic point of view, the advantage is a designable framework, which can readily be constructed from building blocks, the so-called bottom-up assembly. Compared with conventional porous materials such as zeolites and activated carbons, porous inorganic-organic hybrid frameworks have higher potential for adsorption of small molecules because of their designability with respect to the coordination geometry around the central metal ion as well as size and probable multifunctionality of bridging organic ligands. Although rigidity and robustness of porous framework with different degree of adsorption are the most studied properties of metal-organic coordination frameworks, there are few studies on dynamic porous frameworks, which could open up a new dimension in materials chemistry.

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Ahmed, Adham, Rob Clowes, Elizabeth Willneff, Peter Myers, and Haifei Zhang. "Porous silica spheres in macroporous structures and on nanofibres." Philosophical Transactions of the Royal Society A: Mathematical, Physical and Engineering Sciences 368, no. 1927 (September 28, 2010): 4351–70. http://dx.doi.org/10.1098/rsta.2010.0136.

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Porous nanospheres have a wide range of applications such as in catalysis, separation and controlled delivery. Among these nanospheres, syntheses and applications of porous silica nanospheres have been investigated extensively. Uniform porous silica nanospheres can be synthesized using a modified Stöber method. In the present study, porous silica spheres were prepared in the pre-formed emulsion-templated porous polyacrylamide (PAM). A hierarchical hybrid structure of mesoporous silica spheres was formed in the highly interconnected macroporous polymer. The polymer scaffold could be removed by calcination with porous silica spheres and the macroporous structures retained. This resulted from the close packing or aggregation of small silica nanospheres in the pores and on the surface of pores of PAM. The modified Stöber synthesis was further carried out in pre-formed polymer nanofibres (chitosan and sodium carboxymethyl cellulose). The structure of porous silica spheres on nanofibres was produced in the presence of the polymer or composite fibres. The corresponding inorganic structures were successfully obtained after calcination. The hierarchical structures of porous nanospheres within macroporous structures or on nanofibres are of potential interest to researchers in nanomaterials, porous polymers, supported catalysis and controlled delivery.

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HU, ZHIGANG, and DAN ZHAO. "POLYMERIZATION WITHIN CONFINED NANOCHANNELS OF POROUS METAL-ORGANIC FRAMEWORKS." Journal of Molecular and Engineering Materials 01, no. 02 (June 2013): 1330001. http://dx.doi.org/10.1142/s2251237313300015.

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Metal-organic frameworks (MOFs) have been increasingly investigated as templates for precise control of polymerization. Polymerizations within confined nanochannels of porous MOFs have shown unique confinement and alignment effect on polymer chain structures and thus are promising ways to achieve well-defined polymers. Herein, this review will focus on illustrating the recent progress of polymerization within confined nanochannels of MOFs, including radical polymerization, coordination polymerization, ring-opening polymerization, catalytic polymerization, etc. It will demonstrate how the heterogeneous MOF structures (pore size, pore shapes, flexible structures, and versatile functional groups) affect the polymeric products' molecular weight, molecular weight distribution, tacticity, reaction sites, copolymer sequence, etc. Meanwhile, we will highlight some challenges and foreseeable prospects on these novel polymerization methods.

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Koler, Amadeja, Jiři Brus, and Peter Krajnc. "RAFT Polymerisation and Hypercrosslinking Improve Crosslink Homogeneity and Surface Area of Styrene Based PolyHIPEs." Polymers 15, no. 10 (May 10, 2023): 2255. http://dx.doi.org/10.3390/polym15102255.

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The influence of a polymerisation mechanism (reversible addition–fragmentation chain transfer; RAFT vs. free radical polymerisation; FRP) on the porous structure of highly porous poly(styrene-co-divinylbenzene) polymers was investigated. The highly porous polymers were synthesised via high internal phase emulsion templating (polymerizing the continuous phase of a high internal phase emulsion), utilising either FRP or RAFT processes. Furthermore, residual vinyl groups in the polymer chains were used for the subsequent crosslinking (hypercrosslinking) applying di-tert-butyl peroxide as the source of radicals. A significant difference in the specific surface area of polymers prepared by FRP (between 20 and 35 m2/g) and samples prepared by RAFT polymerisation (between 60 and 150 m2/g) was found. Based on the results from gas adsorption and solid state NMR, it could be concluded that the RAFT polymerisation affects the homogeneous distribution of the crosslinks in the highly crosslinked styrene-co-divinylbenzene polymer network. During the initial crosslinking, RAFT polymerisation leads to the increase in mesopores with diameters between 2 and 20 nm, resulting in good accessibility of polymer chains during the hypercrosslinking reaction, which is reflected in increased microporosity. The fraction of micropores created during the hypercrosslinking of polymers prepared via RAFT is around 10% of the total pore volume, which is up to 10 times more than for polymers prepared by FRP. Specific surface area, mesopore surface area, and total pore volume after hypercrosslinking reach almost the same values, regardless of the initial crosslinking. The degree of hypercrosslinking was confirmed by determination of the remaining double bonds by solid-state NMR analysis.

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Koromilas, Nikos D., Charalampos Anastasopoulos, Evdokia K. Oikonomou, and Joannis K. Kallitsis. "Preparation of Porous Polymeric Membranes Based on a Pyridine Containing Aromatic Polyether Sulfone." Polymers 11, no. 1 (January 2, 2019): 59. http://dx.doi.org/10.3390/polym11010059.

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Polymeric membranes, based on a polysulfone-type aromatic polyether matrix, were successfully developed via the non-solvent induced phase separation (NIPS) method. The polyethersulfone type polymer poly[2-(4-(diphenylsulfonyl)-phenoxy)-6-(4-phenoxy) pyridine] (PDSPP) was used as the membrane matrix, and mixed with its sulfonated derivative (SPDSPP) and a polymeric porogen. The SPDPPP was added to impart hydrophilicity, while at the same time maintaining the interactions with the non-sulfonated aromatic polyether forming the membrane matrix. Different techniques were used for the membranes’ properties characterization. The results revealed that the use of the non-sulfonated and sulfonated polymers of the same polymeric backbone, at certain compositions, can lead to membranes with controllable porosity and hydrophilicity.

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Herrera-Quintero, Julia, Gustavo Maya-Toro, Kelly Colmenares-Vargas, Juliana Vidal-Prada, Dalje Barbosa-Trillos, and Eduin Muñoz-Mazo. "Influence of physicochemical variables on polymer adsorption in porous media." DYNA 89, no. 220 (March 23, 2022): 9–18. http://dx.doi.org/10.15446/dyna.v89n220.97440.

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HPAM type polymers and modifications with ATBS (Acrylamide Tertiary Butyl Sulfonated) units are used for EOR processes. Polymer adsorption is key to the success of these processes and is affected by variables such as molecular weight, hydrolysis, salinity, and permeability of the porous medium. Nevertheless, few studies corelate the dependence of these variables with adsorption. This work presents experimental results of the influence of variables on the dynamic adsorption of different polymers using sandstone type porous media. Modified polymers show adsorption less than 10 μg/g in low permeability and Sor condition. The adsorption of modified HPAM and HPAM polymers has an inverse relationship with molecular weight and permeability. At higher molecular weight, fewer pores are accessed due to their hydrodynamic radius and lower permeability, greater mechanical and hydrodynamic retention. Water salinity and hardness are directly related to adsorption, with less influence for modified HPAM.

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Liu, Shilin, Kuan He, Xia Wu, Xiaogang Luo, and Bin Li. "Surface modification of cellulose scaffold with polypyrrole for the fabrication of flexible supercapacitor electrode with enhanced capacitance." RSC Advances 5, no. 106 (2015): 87266–76. http://dx.doi.org/10.1039/c5ra17201b.

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Zhu, Wenxiao, Yun Zhu, Ce Zhou, and Shengmiao Zhang. "Pickering emulsion-templated polymers: insights into the relationship between surfactant and interconnecting pores." RSC Advances 9, no. 33 (2019): 18909–16. http://dx.doi.org/10.1039/c9ra03186c.

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Pickering high internal phase emulsions (HIPEs) stabilized by micron-size polymer particles were developed, and the relationship between surfactant and interconnecting pores of these HIPE-templated porous polymers was experimentally clarified.

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Jung, Youngmee, Su Hee Kim, Sang-Heon Kim, and Soo Hyun Kim. "New fabrication methods of bioactive and biodegradable scaffolds for bone tissue engineering." Journal of Cellular Plastics 47, no. 3 (May 2011): 261–70. http://dx.doi.org/10.1177/0021955x11405465.

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Bioceramic and polymers have been used as matrices for bone tissue engineering, and successful bone regeneration depends on cellular interaction with these matrices. The aim of this study was to fabricate polymer/ceramics composites with a novel sintering method. Also, we prepared homogenous porous poly(lactide-co-glycolide (PLGA) scaffolds in the supercritical CO2. These scaffolds had homogenous porous structure and high tensile and compressive mechanical properties compared to the scaffold prepared by conventional solvent casting method. This study revealed that generating bioactive and porous polymer scaffolds with novel sintering method or supercritical fluid technique could be useful for bone tissue engineering.

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Kim, Y., Soo Ryong Kim, Kun Hang Cho, Seong Youl Bae, and Woo Teck Kwon. "Preparation of SiC Nanoporous Membrane for Hydrogen Separation at High Temperature." Materials Science Forum 510-511 (March 2006): 926–29. http://dx.doi.org/10.4028/www.scientific.net/msf.510-511.926.

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Nanoporous SiC membrane was developed on the porous alumina plate for the hydrogen separation using preceramic polymers such as polyphenylcarbosilane. The prepared preceramic polymers were characterized with FT-IR, TGA, GPC and XRD. Nanoporous SiC membrane was derived from the preceramic polymer using a spin coating method. The SiC membrane spin coated using 20 wt.% of polyphenylcarbosilane solution in cyclohexane does not show any cracks on the surface after heat treatment at 800oC. The average thickness of the SiC membrane is about 1µm. SiC coated porous alumina possesses asymmetric pore size distribution. There are micropores that originated from porous alumina substrate, and nanopores that derived from amorphous state of SiC membranes. The pore size distribution measurement showed that the sample contains 1-3 nm sized nano pores.

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Li, Bao-Ning, Xing-Long Zhang, Xiao-Hui Bai, Zhen-Jie Liang, Jian Li, and Xiao-Yong Fan. "Electron-Rich Triazine-Conjugated Microporous Polymers for the Removal of Dyes from Wastewater." Molecules 28, no. 12 (June 15, 2023): 4785. http://dx.doi.org/10.3390/molecules28124785.

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Conjugated microporous polymers (CMP) as porous functional materials have received considerable attention due to their unique structures and fascinating properties for the adsorption and degradation of dyes. Herein, a triazine-conjugated microporous polymer material with rich N-donors at the skeleton itself was successfully synthesized via the Sonogashira–Hagihara coupling by a one–pot reaction. These two polymers had Brunauer–Emmett–Teller (BET) surface areas of 322 and 435 m2g−1 for triazine-conjugated microporous polymers (T-CMP) and T-CMP-Me, respectively. Due to the porous effects and the rich N-donor at the framework, it displayed a higher removal efficiency and adsorption performance compared to cationic-type dyes and selectivity properties for (methylene blue) MB+ from a mixture solution of cationic-type dyes. Furthermore, the T-CMP-Me could quickly and drastically separate MB+ and (methyl orange) MO− from the mixed solution within a short time. Their intriguing absorption behaviors are supported by 13C NMR, UV−vis absorption spectroscopy, scanning electron microscopy, and X-ray powder diffraction studies. This work will not only improve the development of porous material varieties, but also demonstrate the adsorption or selectivity of porous materials for dyes from wastewater.

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Setnickova, Katerina, Karel Jerabek, Tomas Strasak, Monika Mullerova, Vera Jandova, Karel Soukup, Roman Petrickovic, Hui-Hsin Tseng, and Petr Uchytil. "Synthesis, Characterization, and Gas Adsorption Performance of Amine-Functionalized Styrene-Based Porous Polymers." Polymers 15, no. 1 (December 20, 2022): 13. http://dx.doi.org/10.3390/polym15010013.

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In recent years, porous materials have been extensively studied by the scientific community owing to their excellent properties and potential use in many different areas, such as gas separation and adsorption. Hyper-crosslinked porous polymers (HCLPs) have gained attention because of their high surface area and porosity, low density, high chemical and thermal stability, and excellent adsorption capabilities in comparison to other porous materials. Herein, we report the synthesis, characterization, and gas (particularly CO2) adsorption performance of a series of novel styrene-based HCLPs. The materials were prepared in two steps. The first step involved radical copolymerization of divinylbenzene (DVB) and 4-vinylbenzyl chloride (VBC), a non-porous gel-type polymer, which was then modified by hyper-crosslinking, generating micropores with a high surface area of more than 700 m2 g−1. In the following step, the polymer was impregnated with various polyamines that reacted with residual alkyl chloride groups on the pore walls. This impregnation substantially improved the CO2/N2 and CO2/CH4 adsorption selectivity.

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Singh, Anupama, and Deepti Saini. "Triazine based porous organic polymers." Nano and Medical Materials 3, no. 1 (March 21, 2023): 2. http://dx.doi.org/10.59400/nmm.v3i1.33.

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Porous organic polymers (POPs) are an important class of organic materials that can be used for various purposes like hydrogen storage, lithium batteries, and CO2 capture from the environment. Triazine itself has a vast array of use as it contains nitrogen at its three edges which can be efficiently used to synthesize nano architectonic porous organic polymers.

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Solomon, Marcello B., Peter D. Southon, Aditya Rawal, James M. Hook, Katrina A. Jolliffe, and Deanna M. D'Alessandro. "Salen-Based Metal Complexes and the Physical Properties of their Porous Organic Polymers." Australian Journal of Chemistry 72, no. 11 (2019): 916. http://dx.doi.org/10.1071/ch19069.

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Porous organic polymers (POPs) represent interesting candidate materials for carbon dioxide (CO2) adsorption applications owing to the permanently porous nature of the structures and the ability to vary metalloligand centres that can be incorporated as a potential means of property tuning. This work reports the synthesis and characterisation of four transition metal complexes (using M=Mn, Ni, Fe, and Pd) of the bis-bromo salen ligand, and the incorporation of these complexes into POPs with tris-(p-ethynyl)-triphenylamine to yield metallated polymers (POPMn, POPNi, POPFe, and POPPd). The POPs were shown to possess Brunauer–Emmett–Teller (BET) surface areas of up to 650m2g−1. Overall, this work provides further insight into the potential of permanently porous polymeric materials in post-combustion capture applications.

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Journal articles on the topic 'Porous Polymers'

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