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The unique properties of gels, particularly polymer based gels have drawn attention of the researchers since ages. This review highlights the fundamental aspects of polymeric gels, enumerating them in terms of differences in synthesis or crosslinking mechanism. To broaden the possibility of these polymeric gels to decontaminate textile effluents co...
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... like the nature of crosslinking, solvent uptake ability, viscoelasticity directly influence the stability of the gels. Usually, polymeric gels can swell by absorbing large amount of solvent without dissolving itself into it (Figure 1). To quantify the solvent uptake ability of the gels, swelling ratio is measured by computing the weight ratio of gels in dry and wet state. ...
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... Norrish type I initiators such as lithium phenyl-2,4,6-trimethylbenzoylphosphinate (LAP), Irgacure 2959 are the widely used photoinitiators under UV light, for their effective thiyl radical generation. [79,80] The mechanism of photo-initiated thiol-norbornene reaction is depicted in Figure 10. [81] On the contrary, Hawker et al. have compared the competency of photoinitiation with the thermally initiated thiol-ene reaction. ...
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... instance, Anseth et al. have compared the efficacy of thiol-norbornene versus thiol-acrylate photocrosslinking reaction toward encapsulation of proteins and preserving their bioactivity ( Figure 11). [84] It was observed that the lysosome activity reduced to 50% post exposure to acrylate, but it maintained almost 100% pre-reaction activity post exposure to thiol-norbornene reaction. ...
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... these dyes, after its use, are disseminated into the waterways regardless of their perilous environmental impact. Figure 12 illustrates that five different industrial sectors are primarily responsible for the presence of dye effluents in the water bodies. [94] Among these five industries, textile industries are known to discard the largest portion (54%) of the dye effluents globally, followed by dyeing (21%), paper (10%), paint (8%) and dye manufacturing (7%) industries ( Figure 12). ...
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... 12 illustrates that five different industrial sectors are primarily responsible for the presence of dye effluents in the water bodies. [94] Among these five industries, textile industries are known to discard the largest portion (54%) of the dye effluents globally, followed by dyeing (21%), paper (10%), paint (8%) and dye manufacturing (7%) industries ( Figure 12). [94] Every year, textile sector alone utilizes more than 10,000 tonnes of dyes worldwide that eventuates the production of more than 100 tonnes of dye effluents in a year. ...
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... dyes can be classified based on the source of their procurement i.e., natural or synthetic dyes. Dyes can also be categorized on the basis of their chemical composition and their application to the substrate, such as: anionic, cationic and nonionic ( Figure 13). [97] Further, dyes can be classified in terms of their solubility in water: acid dyes, basic dyes, reactive dyes are water soluble whereas disperse dyes, vat dyes, sulfur dyes are water insoluble. ...
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... Authors have varied the NIPAAm content in the gel to obtain a particular composition that is efficient toward dye removal. Similarly, Sun et al. have recently reported the fabrication of a poly (acrylic acid) (PAA) based nanocomposite hydrogel, which is capable of removing cationic dye methylene blue dye from water ( Figure 14). [129] For synthesis of the adsorbent, they have employed free radical polymerization of acrylic acid and calcium hydroxide (Ca(OH) 2 ) nano-spherulites was used as potential crosslinkers. ...
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... was observed that the removal efficiency of the gels enhanced with increase in pH of the solution. Besides, Ray et al. have developed a superabsorbent nano-clay filled hydrogel which was synthesized via free radical polymerization of acrylic acid monomer, N' N' methylene bis acrylamide (MBA) crosslinker in presence of PEG, that is capable of removing both Congo red and methyl violet dyes from aqueous phase (Figure 15). [135] Further, Shunmugam et al. have recently developed thiolnorbornene based photo-crosslinked gel system that qualifies as an efficient adsorbent to decontaminate wastewater. ...
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... Interestingly, this material does not swell in water, however it is competent in removing toxic cationic dyes rhodamine B and methylene blue from aqueous medium. Later, they have introduced PEG of different molecular weights to the norbornene backbone and subsequently to the crosslinked network ( Figure 16). [14] Reasonably, the water uptake ability of the so formed gels enhanced with increase in PEG chain in the network. ...
Citations
... Regarding the effects of SAPs on the fate of agrochemicals and other soil contaminants, current studies indicate a SAP-induced reduction in contaminant mobility and toxicity. The sorption behavior of SAP hydrogels is generally well-researched for metals and dyes (Hüttermann et al., 2009;Bhattacharya and Shunmugam, 2020;Venkatachalam and Kaliappa, 2023). For instance, Dhiman et al. (2020) observed a higher retention and reduced plant uptake of Cd, Cu and Zn in soil after PAM amendments. ...
The extensive use of synthetic polymers in our everyday lives has resulted in significant plastic pollution. Superabsorbent polymers (SAPs) are yet another class of anthropogenic materials with uncertain environmental implications. SAPs, like polyacrylates (PAA) or polyacrylamides (PAM), find applications in personal care products, construction, wastewater treatment, agriculture and soil remediation. However, when SAPs enter the soil, weathering may change their intended properties, potentially forming plastic-like solid residues over time. This review aims to evaluate the current scientific understanding of the application and environmental fate of SAPs in soil, focusing on the processes driving their potential transformation into solid residues. We explore analytical techniques for the qualitative and quantitative characterization of SAPs and solid SAP residues. Our research provides first insights into the potential mechanisms and conditions governing SAP aging and transformation, advancing our understanding of the fate of SAPs in soil and their impact on soil properties and functioning. There are specific knowledge gaps regarding the influence of climate change on the application and transformation of SAPs in soil. To facilitate future research, we suggest scrutinizing relevant processes of SAP transformation in the field, critically (re)evaluating SAP application to the soil and establishing robust monitoring methods.
... The use of raw, economic and low cost adsorbents with high absorption capacity is essential and advantage in the adsorption technique and which can also reduce the cost of wastewater treatment [22,23]. Various adsorbents such as clays, polymers, and their hybrid systems were commonly used for the removal of various contaminants from aqueous solutions [24][25][26][27][28][29]. Polymers have the ability to adsorb a wide variety of organic structures by virtue of their unique characteristics, but they have some disadvantages, mainly particle size sensitivity, poor water dissolution, dependence and sensitivity to pH. ...
This work describes the preparation of new eco-friendly adsorbents with a simple method. At first, Montmorillonite (MMT) was modified with surfactant HTAB (MMT@HTAB) and then with polymer PEG (MMT@HTAB@PEG). The as-synthesized materials were characterized by several characterization techniques, including XRD, FTIR, SEM, TEM, TGA, N2 adsorption/desorption isotherm analysis by the BET method and zeta potential measurement then evaluated as adsorbents for removal of both methylene blue (MB) as a cationic dye and trypan blue (TB) as the anionic dye from aqueous solution under different contact time, dye concentration, temperature, and pH. The obtained results confirm the intercalation of surfactant within the clay layers, while the obtained nanocomposite showed different morphologies and structures in which the exfoliated and intercalated forms were obtained. The maximum adsorption capacity of TB and MB was found to be 190.81 and 237.22 mg/g, respectively, with MMT@HTAB@PEG adsorbent in an initial concentration of 100 mg/L at alkaline pH in 35 min and a temperature of 25 °C. The adsorption kinetics of TB and MB on MMT@HTAB@PEG was best fitted by the pseudo-second order model, and the isotherms results reveals better consistency of the Langmuir model, indicating that the adsorption is favorable and in the form of multilayers. The thermodynamic study showed that the adsorption processes of TB and MB by the both MMT@HTAB and MMT@HTAB@PEG adsorbents occur in an autonomous way and the temperature has not a significant effect on the adsorption capacity of TB and MB dyes. In addition, MMT@HTAB showed good antibacterial activity against both Escherichia coli (ATCC 8739) and Micrococcus luteus (ATCC 9341) bacteria compared to MMT@HTAB@PEG. The broadcast area was found to be 6 and 5 mm in Escherichia coli (ATCC 8739) and Micrococcus luteus (ATCC 9341), respectively.
... Depending on the variation of the external environment, like physical stimuli (temperature, electric and magnetic field, light, pressure) and/or chemical stimuli (pH, ionic strength, molecular species, and solvent composition), the polymer gels can discontinuously and reversibly change their volume [10,11]. Polymeric gels have the capacity to absorb a significant amount of water (tens to hundreds of times greater than the polymer itself) or biological fluids due to the existence of a hydrophilic component [12,13]. The polymer gel can swell until an equilibrium state is established between the osmotic forces and the ability to expand the polymer chains [14][15][16]. ...
Polymer gels are a valuable class of polymeric materials that have recently attracted significant interest due to the exceptional properties such as versatility, soft-structure, flexibility and stimuli-responsive, biodegradability, and biocompatibility. Based on their properties, polymer gels can be used in a wide range of applications: food industry, agriculture, biomedical, and biosensors. The utilization of polymer gels in different medical and industrial applications requires a better understanding of the formation process, the factors which affect the gel’s stability, and the structure-rheological properties relationship. The present review aims to give an overview of the polymer gels, the classification of polymer gels’ materials to highlight their important features, and the recent development in biomedical applications. Several perspectives on future advancement of polymer hydrogel are offered.
... Hence, several types of adsorbents were investigated for dyes' elimination including biochar and activated carbon (Tarelho et al. 2020;Pereira et al. 2003;Moosavi et al. 2020), metal oxidebased nanoparticles (Kumar et al. 2013;Li et al. 2015), metal-organic framework (MOF) (Au VK-M. 2020;Jamal Uddin et al. 2021), bio-adsorbents [Matias et al. 2019, El Atouani et al. 2019, Gardazi S M H. 2014, polymer-based materials (Sayantani and Shunmugam 2020;Panic et al. 2013;Jayaramudu et al. 2021;Mok et al. 2020) and others. ...
The approach of the present paper is based on the study of methylene blue (MB) dye adsorption onto new biocomposite microspheres. The microparticles are composed of red wood powder and cellulose derivatives (ethylcellulose and cellulose acetate) and are prepared by emulsion-solvent evaporation process by varying some of the process parameters such as organic phase concentration (RW%), emulsifier concentration (PVA%) and stirring speed of emulsion (N). The obtained microparticles are characterized by infrared spectroscopy, X-ray diffraction, optical microscopy and scanning electron microscopy, the mean diameters of microparticles and pHpzc are also measured. Designs of experiments (DOE) are used for both the preparation and optimization of microparticles and MB removal study. The MB adsorption tests are carried out onto the optimized spherical microparticles with mean diameter (d32) of 321–334 µm where effects of selected variables i.e. RW%, temperature and MB initial concentration are analyzed and identified. Thus, statistical relationships between responses which are adsorption percentage (Ads. eq. %) and capacity (qe) at equilibrium and variables are determined. The results demonstrated synergistic effects of both RW% and MB initial concentration and an adversary effect of temperature on qe. The Ads.eq. % achieved 92% at a low MB initial concentration of 20 mg L−1.
... Chemical adsorption methods can effectively adsorb these organic pollutants due to their high efficiency, low cost, and simple operation [15]. In recent years, gel-based adsorbents have been widely employed in the treatment of organic pollutants [16]. Aerogels and xerogels are widely applied as adsorbents for organic dyes and phenolic pollutants due to their low density and high porosity [17,18]. ...
Organogel adsorbents are widely used for the adsorption of hard-to-degrade organic pollutants in wastewater due to their natural affinity to the organic phase in water. In this study, phenolic xerogels (PF) synthesised in the ethylene glycol inorganic acid system are used as a backbone and superhydrophobic phenolic xerogels (ASO-PF) are obtained by grafting aminosilanes onto the PF backbone via the Mannich reaction. The modified ASO-PF not only retains the pore structure of the original PF (up to 90% porosity), but also has excellent superhydrophobic properties (water contact angle up to 153°). Owing to the unique pore structure, ASO-PF has excellent compression properties, cycling 50% compression deformation more than 10 times without being damaged, with a maximum compression deformation of up to 80%. A squeeze–suction–squeeze approach is proposed for selective adsorption of organic pollutants in homogeneous solutions based on the recyclable compression properties of ASO-PF. The ASO-PF is put under negative pressure by squeezing, and when the pressure is released, the adsorbed liquid enters the ASO-PF, where the organic pollutants are retained by the adsorption sites in the skeleton, and then the remaining water is discharged by squeezing. This breathing ASO-PF holds great promise for organic pollutant adsorption and recovery applications.
... [1][2][3] Today, the use of carbon structures and polymers in industry and the manufacture of various compounds to remove pollutants, biosensors, drug delivery, the construction industry is very significant. [4][5][6][7][8][9] Polymers are a flammable substrate, and annual fires have always caused irreparable damage to humans and their environment. Due to the widespread use of epoxy in industry, warehouses, educational and sports centers in today's world, scientists think that they have improved the safety of using epoxy coatings. ...
In this project, a novel flame retardant was synthesized using a modification of epoxy resin with phenylboronic acid in the presence of tetra-n-butyl ammonium bromide catalyst during reaction at 80–120 °C. The flame retardant was prepared from the polymerization process without solvent and two ratios of phenylboronic acid. Then, using this obtained material, epoxy coating formula 828 was prepared and the effect of adding this compound was investigated then by examining the properties, the optimal sample was obtained. The results of the FTIR, NMR, TGA and DSC analysis confirmed the successful synthesis of flame retardant compounds. The curves obtained from the calorimetric test showed an increase in the efficiency of coal production and thermal resistance of the samples containing flame retardants. The rate of thermal degradation of the samples decreased from 100% for the pure epoxy coating to 94% and 87% for BE1 and BE2 samples containing flame retardant, respectively. The limited oxygen index increased from 21.8% for the pure epoxy sample to 26.6% and 31.2% for BE1 and BE2 samples, respectively. Examination of flame resistance properties showed that the coating containing 20% by weight of flame retardant BE2 had better results.
... Polymeric probes are being used in several sensing [30,31] and real-life applications to overcome the problems faced by small molecular probes. Recently, our group has published several articles on polymeric sensors [32,33] for the selective detection of metals [34,35] and volatile organic compounds [36,37]. ...
Formaldehyde is a well-known industrial material regularly used in fishery, vegetable markets, and fruit shops for maintaining their freshness. But due to its carcinogenic nature and other toxic effects, it is very important to detect it in very low concentrations. In recent years, amine-containing fluorescent probes have gained significant attention for designing formaldehyde sensors. However, the major drawbacks of these small molecular probes are low sensitivity and long exposure time, which limits their real-life applications. In this regard, polymeric probes have gained significant attention to overcome the aforementioned problems. Several polymeric probes have been utilized as a coating material, nanoparticle, quartz crystal microbalance (QCM), etc., for the selective and sensitive detection of formaldehyde. The main objective of this review article is to comprehensively describe the recent advancements in formaldehyde sensors based on small molecules and polymers, and their successful applications in various fields, especially in situ formaldehyde sensing in biological systems.
... Hyaluronic acid (HyA) is a natural linear polysaccharide, being naturally present and abundant in all biologic fluids of some bacteria and all vertebrates [2][3][4]. Due to its biocompatibility, biodegradability and presence in the native extracellular matrix of tissues [5], HyA has been extensively applied for medical [6,7] and biomedical applications [8,9], including drug delivery [10][11][12], bioprinting [13] and tissue engineering [14], cosmetics [15] and wastewater treatment [16]. For most of these applications, knowledge of the transport properties of HyA in aqueous solutions plays a key role. ...
... Equation (15) can be significantly simplified to: app D 1Tracer = D 11 + R 2 R 1 D 21 (16) to obtain an apparent tracer diffusion coefficient, app D 1Tracer , for solute 1. This pseudobinary treatment ignores the fact that tracer ionic diffusion in a supporting electrolyte is a multicomponent process involving coupled diffusion of the supporting electrolyte and, consequently, does not allow accurate prediction of tracer diffusion coefficients of NaHy. ...
Tracer diffusion coefficients obtained from the Taylor dispersion technique at 25.0 °C were measured to study the influence of sodium, ammonium and magnesium salts at 0.01 and 0.1 mol dm−3 on the transport behavior of sodium hyaluronate (NaHy, 0.1%). The selection of these salts was based on their position in Hofmeister series, which describe the specific influence of different ions (cations and anions) on some physicochemical properties of a system that can be interpreted as a salting-in or salting-out effect. In our case, in general, an increase in the ionic strength (i.e., concentrations at 0.01 mol dm−3) led to a significant decrease in the limiting diffusion coefficient of the NaHy 0.1%, indicating, in those circumstances, the presence of salting-in effects. However, the opposite effect (salting-out) was verified with the increase in concentration of some salts, mainly for NH4SCN at 0.1 mol dm−3. In this particular salt, the cation is weakly hydrated and, consequently, its presence does not favor interactions between NaHy and water molecules, promoting, in those circumstances, less resistance to the movement of NaHy and thus to the increase of its diffusion (19%). These data, complemented by viscosity measurements, permit us to have a better understanding about the effect of these salts on the transport behaviour of NaHy.
Due to their unique adsorptive potentials, graphene-based nano-composites [especially graphene oxide (GO)] have been recently researched intensively for sequestrating organic pollutants, such as dyes and pharmaceuticals. These pollutants are primarily adsorbed via π–π, H-bond, and electrostatic interactions, achieving 37–1148 mg g⁻¹ maximum adsorption capacities. This review identifies the influence of pH, temperature, sorbate concentration, and sorbent dosage on the sorbate-sorbent interface. The investigated adsorptions occurred within pH 2–12, promoting cationic surfaces that achieved up to 394.6 mg g⁻¹. Also, both dyes and pharmaceuticals were predominantly removed endothermically (≥ 532.6 mg g⁻¹) than exothermically (≥ 14.10 mg g⁻¹). Further reusability tests over 3–15 cycles accomplished between > 50 and 100% removal efficiencies. In comparison, zeolites were other adsorbents with similar performances to functionalized GO, except that GO exhibits superior affordability, mechanical strength, specificity, and reusability. However, simultaneous removal of dyes and pharmaceuticals using GO requires further research for improved performance.
