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Magnetic superabsorbents have been successfully synthesized through aqueous solution polymerization, employing sodium alginate as the backbone material, acrylic acid and acrylamide as the polymeric monomers, Fe3O4 nano-particles as the magnetic component, N,N'-methylenebisacrylamide as the crosslinking agent, and ammonium persulfate serving as the initiator. The micro-morphology and thermal stability of these superabsorbents were thoroughly characterized using scanning electron microscopy (SEM), confocal laser scanning microscopy (CLSM), X-ray diffraction (XRD), and thermogravimetric analysis (TGA), respectively. A comprehensive investigation was undertaken to examine the swelling capacity, water retention properties, magnetic responsiveness, and reusability of the magnetic superabsorbents. The findings reveal that these superabsorbents possess an impressive maximum water absorption capacity of 302.7 g/g in distilled water. Notably, their swelling ratios maintain high levels within a pH range of 5–10. Featuring a porous structure, the magnetic superabsorbents demonstrate rapid swelling kinetics, attaining swelling equilibrium within 30 min in a 1 wt% NaCl solution. Furthermore, the superabsorbents exhibit excellent magnetic responsiveness, characterized by a maximum saturation magnetization of 7.91 emu/g, allowing for swift separation under an external magnetic field. Lastly, the magnetic superabsorbents display outstanding reusability, with their water absorption capacity in distilled water still exceeding 90% of the initial swelling ratio after seven reuse cycles. [ABSTRACT FROM AUTHOR]

Magnetic superabsorbents have been successfully synthesized through aqueous solution polymerization, employing sodium alginate as the backbone material, acrylic acid and acrylamide as the polymeric monomers, Fe3O4 nano-particles as the magnetic component, N,N'-methylenebisacrylamide as the crosslinking agent, and ammonium persulfate serving as the initiator. The micro-morphology and thermal stability of these superabsorbents were thoroughly characterized using scanning electron microscopy (SEM), confocal laser scanning microscopy (CLSM), X-ray diffraction (XRD), and thermogravimetric analysis (TGA), respectively. A comprehensive investigation was undertaken to examine the swelling capacity, water retention properties, magnetic responsiveness, and reusability of the magnetic superabsorbents. The findings reveal that these superabsorbents possess an impressive maximum water absorption capacity of 302.7 g/g in distilled water. Notably, their swelling ratios maintain high levels within a pH range of 5–10. Featuring a porous structure, the magnetic superabsorbents demonstrate rapid swelling kinetics, attaining swelling equilibrium within 30 min in a 1 wt% NaCl solution. Furthermore, the superabsorbents exhibit excellent magnetic responsiveness, characterized by a maximum saturation magnetization of 7.91 emu/g, allowing for swift separation under an external magnetic field. Lastly, the magnetic superabsorbents display outstanding reusability, with their water absorption capacity in distilled water still exceeding 90% of the initial swelling ratio after seven reuse cycles. [ABSTRACT FROM AUTHOR]

Superabsorbent starch (SS) was coated on Zn foil by a simple scratch coating method to form an artificial interface protection layer, which inhibited the formation of dendrites by guiding the uniform deposition of Zn2+. In addition, SS coating contains a large amount of OH–, which can promote the desolvation process of hydrated Zn2+ and inhibit the side reaction. [Display omitted] Aqueous zinc ion batteries (AZIBs) have attracted much attention for their safety, low cost and high theoretical capacity. Nevertheless, Zn dendrites and the adverse reactions such as corrosion, hydrogen evolution and passivation on the anode affect the cycle life and stability of AZIBs. Herein, superabsorbent starch (SS) was employed on Zn foil to form an artificial interface protection layer, which inhibited the formation of dendrites by guiding the uniform deposition of Zn2+. SS with a large amount of oxygen-containing functional group is superabsorbent, which can attract the active water around the hydrated Zn2+, promoting the desolvation process of the hydrated Zn2+ and significantly inhibiting the occurrence of hydrogen evolution reaction. In addition, the inherent pore structure of the SS artificial interfacial layer can induce uniform nucleation of Zn2+ and inhibit the dendrites growth. Moreover, compared to bare Zn//MnO 2 cell (44.1 %), the capacity retention of Zn@SS//MnO 2 cell remained as high as 87.8 % after 1000 cycles at 1.5 A g−1. The simple method provided a new method for the rapid development of AZIBs. [ABSTRACT FROM AUTHOR]

Nanogels (Ngl) have emerged as one of the most prominent and convenient systems to act as site-specific drug delivery systems and antimicrobial agents for a varied range of diseases. Super absorbent silver incorporated gelatine-based nanogel (Ngl) grafted with acrylic acid (AAc) (gelatin-grafted-acrylic acid) (SGlAsTC) was synthesized by the chemical polymerization method for use as antimicrobial agents and prospective drug delivery matrices. The nanogel was synthesized employing N, N, Methylene bisacrylamide as a crosslinker and TEMED (N, N, N,N-Tetramethylethylenediamine) as a surfactant. The thus obtained Ngl was characterized by particle size analysis (DLS), FT-R, XRD, EDX, FESEM, and DSC to get evidence of nanogel synthesis. FTIR analysis confirmed the crosslinking reaction with AAc of Ngl, and the spherical morphology studies of SGlAsTC were confirmed by the FESEM image, which showed a sphere-like morphology with porous and crumpled particles. A swelling study was carried out at different pHs (2.2, 4.2, 6.5, 7.4, and 8.2) and at two different temperatures (at 25°C and 37°C) to evaluate the water absorption ability of the synthesized Ngl. The synthesized Ngl was subjected to antimicrobial studies against four different bacteria, exhibiting an exceptional inhibition zone for SGlAsTC against Pseudomonas aeruginosa. Excellent results were observed for SGlAsTC against the bacteria compared to the positive control (azithromycin). The results could be attributed to gelatin molecules that facilitated the absorption of the silver-incorporated AAc chains into the bacterial cell wall and speeded up the destruction of the cell cytoplasm. [ABSTRACT FROM AUTHOR]

Geobotany, as a useful tool in the exploration of minerals, has found a lot of use in environmental studies and the cleaning of contaminated environments. Chalpo is located 45 km north of Kashmer city (Khorasan Razavi). Due to the occurrence of antimony-gold deposit and geological and geochemical characteristics along with the specific vegetation of the region, the geobotanical study of the plants of the area was carried out to identify mineral indicator plants, introduce endemic plants and the geochemical effect of the region on important metallophytes. Sampling was done in precise and specific steps from the plant organs and the soil where the roots of the plants are located. The amount of elements in the soil, root and shoot samples of the plant was compared. Based on the results of chemical analyses, the arsenic content of all plant species is higher than the normal level in plants. Ih has measured above 2000 ppm arsenic in Asperula glomerata subsp. turcomanica. Most plants concentrated one or more elements higher than normal, which is very important both from the point of view of the exploration of metal minerals and from the environmental studies. Despite the proximity location of the collected samples, the plants showed very different absorption rates in each element. The endemic plant Astragalus hekmat-safaviae with a very high accumulation coefficient of arsenic (9), antimony (25) and molybdenum (51) can be introduced as an absorbent or superabsorbent for these metals and as an accumulator for copper and zinc elements. The Asperula glomerata subsp. turcomanica, one of the typical plants of the region, shows an accumulation coefficient of about 2 for zinc and molybdenum. The Jurinea sp. which was observed in this study for the first time, shows the accumulation coefficient and the transfer coefficient factor higher than one for zinc and molybdenum. [ABSTRACT FROM AUTHOR]

The development of new methods to improve the water absorption performance of polymeric materials, taking into account their environmental friendliness, is a promising research direction in Itaconic acid based water‐absorbent polymeric materials. In this study, from the perspective of environmental protection, we propose to design highly absorbent hydrogels with a novel villous‐like structure by using hydrophilic itaconic acid as the raw material and combining it with a novel villous‐like network structure to substantially increase the contact area between the hydrogel and water, thus improving the water absorption rate of the hydrogel. Itaconic acid is water‐soluble and renewable. The widespread use of polymeric water‐absorbent polymers from traditional petroleum sources poses a serious threat to the sustainability of ecosystems, and therefore, itaconic acid has attracted much attention as an alternative to petroleum‐based polymers. The villous‐like network structure is inspired by the villi of the small intestine, the special presence of which expands the absorptive surface area of the small intestine by a factor of about 600, and it is therefore hypothesized that the introduction of this special structure could help the hydrogel to greatly increase the contact area with water and thus achieve the high water absorption properties of the hydrogel. This is also the first time that the villus‐like network structure has been applied to Itaconic acid based hydrogels. The results show that the hydrogel has the property of rapid water absorption and swelling and the water absorption rate of the hydrogel can reach up to 2210 g/g, and the villous‐like structure formed by the hydrogel can be observed in the SEM image. The water‐absorption test of the hydrogel showed that when the molar mass ratio of itaconic acid to acrylic acid was 1:4, the hydrogel absorbed water and swelled rapidly in a short time. The results of the water retention test showed that the hydrogel still existed after 5 days, and the water retention was greater than 86%. In addition, the hydrogel had high reusability, and the water absorption performance of the hydrogel could still reach 89.12% after 6 cycles of the water absorption test. Hydrogel with high water‐absorbing property has good application prospects as fast swelling material in the field of flood control of water conservancy projects. [ABSTRACT FROM AUTHOR]

Innovative superabsorbent hydrogels were synthesized from watermelon rind (WR), an abundant agricultural waste. The process involved free radical polymerization of acrylic acid (AA) and acrylamide (AAm) with WR particles activated by ammonium persulfate (APS), resulting in (AA-co-AAm)/WR hydrogels with high equilibrium swelling capacities of 749 ± 32 g/g. Notably, after eight cycles, the WR hydrogel maintained 94.88 % of its initial swelling capacity, significantly outperforming the (AA-co-AAm) hydrogel without WR (13.80 % retention). This durability, combined with excellent water retention across various soil textures and high adsorption capacity for methylene blue (MB), underscores the WR hydrogel as a superior soil moisture conservation agent. This study marks a significant advance in recycling organic waste and enhancing water management in agricultural soils, demonstrating the potential for sustainable hydrogel development.

IntroductionThe increasing demands for pulse crops and the lack of water resources in most parts of Iran, especially in dry areas, need to employ new strategies to increase water productivity of pulse crops. One of the new methods in managing water and soil resources is the use of zeolite as a storage tank, which prevents wastage and increases the efficiency of irrigation water particularly in light soils. The purpose of this research was to determine the effect of different amounts of zeolite and irrigation interval on growth and yield indices in Pak cultivar of white beans (Phaseolus vulgaris L.). Materials and MethodsThis research was conducted in order to investigate the effect of different amounts of zeolite and irrigation interval on the growth and grain yield in Pak cultivar of white bean (Phaseolus vulgaris L.), in a split plot design based on randomized complete block design with three replications in a farm located in the bojnord city - north Khorasan in the agronomic year 2023-2024. The study factors included 7, 10 and 13 days irrigation interval in the main plot and three levels of zeolite in the soil (0 (no use), 5 and 10 t.ha-1) in the sub plots. Data were analyzed using SAS 9.4 statistical package and figures were drawn by Excel program. Mean comparison were arranged by least significant differences in the 95% probability. Results and DiscussionThe results revealed that the white bean plants attained their shortest height across all three irrigation levels when zeolite was not applied in the plots. Conversely, when a zeolite level of 10 t.ha-1 was introduced, there was an observed increase of 18.15% in the number of nodes per plant compared to scenarios where no zeolite was utilized. The highest level of zeolite consumption caused an increase of 13.88% in the seed weight compared to the level of no zeolite consumption. The highest seed yield of 4651.5 kg.ha-1was recorded in the 7 day irrigation interval and zeolite consumption of 10 t.ha-1. The lowest amount of electrolyte leakage related to irrigation interval of 10 and 7 days and consumption of 10 t.ha-1 of zeolite was 14.8 and 12.34%, respectively. The consumption of 10 t.ha-1 of zeolite caused a 21% increase in protein compared to the non-use of zeolite in white beans, and with the increase of the irrigation frequency from 7 to 10 days, although the amount of seed protein decreased, it did not have a significant difference with the level of irrigation once every 7 days. And when the irrigation cycle reached once every 13 days, the amount of seed protein decreased significantly by 6.8% compared to the irrigation cycle once every 7 days. It was also found that the addition of 10 tons of zeolite per hectare to the soil caused a 41.5% decrease in the amount of proline in white bean leaves compared to the absence of zeolite. In this research, it was found t.hat the level of 10 t.ha-1 the highest biological yield of 13475 kg.ha-1 recorded and it increased by 29.2% compared to the no zeolite consumption. By reducing the irrigation interval to 10 and 7 days, with the increase of zeolite consumption, the harvest index increased, and in the meantime, the highest index related to the irrigation cycle of 7 days and zeolite consumption of 10 tons was 35.5%. ConclusionsBased on the obtained results, it can be concluded that water stress resulted in a reduction in the growth characteristics and overall performance of white bean plants. The lowest values ​​of parameters calculated in this research were observed at the level of no zeolite consumption and irrigation cycle of 13 days, and their highest values ​​were observed at the level of zeolite of 10 t.ha-1 and irrigation cycle of 7 days, which shows that Zeolite, help more water absorption and water return when the plant needs water, and increase the growth of different plant tissues and production of more products. Overall, it can be inferred that applying zeolite at a rate of 10 t.ha-1, particularly in conjunction with a 7-day irrigation cycle, can optimize the yield and growth characteristics of white beans, specifically the Pak cultivar. However, we recommend further investigation into higher levels of zeolite application across various soil textures to enhance our understanding and refine cultivation practices.

A novel phytic acid-modified corn stalk-composite superabsorbent (PACS-g-p(AA-AM-VP)) with water absorbency of 391 g/g, water retention around 30% at 200 min under 90 °C, adsorption capacities of 284 mg/g and 448 mg/g for Ni(II) and Cu (II), respectively, was synthesized by graft copolymerization of acrylamide(AM), vinyl pyrrolidone(VP) and itaconic acid(IA) with phytic acid-modified corn stalk (PACS) in aqueous solution, using N,N-methylenebisacrylamide (MBA) as a crosslinker and ammonium persulfate (APS) and sodium bisulfite (SBS) as redox initiator. Factors influencing water absorbency and water retention of PACS-g-p (AA-AM-VP), such as PACS amount, initiator amount, crosslinker amount, neutralization degree of IA, IA/VP mass ratio and IA/AM mass ratio, were investigated. Morphologies and structure of PACS-g-p (AA-AM-VP) were characterized by FTIR and SEM. FTIR spectra indicate the structure of phytic acid-modified corn stalk graft-copolymer. SEM data shows that fiber structure of corn stalk is partially destroyed after phytic acid modification under ultrasonic wave. PACS-g-p (AA-AM-VP) has a coarse, fluffy and porous structure, facilitating the permeation of water and heavy metal ions into the polymeric network. Given these properties, PACS-g-p (AA-AM-VP) can be extensively applied in agriculture and horticulture as a water-retaining and soil remediation material which increases agricultural irrigation efficiency and remediates heavy metal-contaminated soil due to its low cost, environmental friendliness, high water retention and good adsorption for heavy metal ions. [ABSTRACT FROM AUTHOR]

The guar gum-polyethylene glycol (GG-PEG) and cellulose acetate-polyethylene glycol (CA-PEG) hydrogel beads have been synthesized using crosslinking agent polyethylene glycol with drop cast method. The newly fabricated beads have been characterized by FTIR, FESEM, TGA and swelling studies. Water retention, water holding, and soil porosity tests have been conducted on both hydrogel beads. The results showed that the swelling ratios for GG-PEG and CA-PEG were 350 g/g and 250 g/g, respectively. At high pressures, GG-PEG retained 20% more water than untreated soil, whereas CA-PEG retained 17.5%. The soil's water-holding capacity improved to 16.05% when treated with GG-PEG, compared to 9.69% with CA-PEG. The porosity of soil increased to 69.45% in the case of GG-PEG hydrogel beads and 65.17% in the case of CA-PEG when compared to untreated soil. The biodegradable studies of the hydrogel beads showed that GG-PEG was more susceptible to degradability since it was a natural polymer. As a result, GG-PEG is more efficient than CA-PEG, and this study demonstrates how natural polymers may be employed as superabsorbents to improve soil qualities by serving as conditioners. [ABSTRACT FROM AUTHOR]

Superabsorbent materials (SAPs) are crosslinked polymer networks composed of ionic and non-ionic monomers. SAPs can absorb and retain water solutions up to several hundred times their own weight. As a result of swelling, they form a gel that is insoluble in water, considered safe and decomposes over time. This review focuses on the synthesis, degradation and chemical composition of SAP materials, with particular emphasis on chemical substances that are soluble in water and can migrate into the environment. Numerous applications of natural and synthetic hydrogels in agriculture and the reclamation of degraded areas in preventing erosion, retention water, reducing leaching of colloidal soil components and plant protection products, fertilisers and mineral salts into surface waters have been described. The influence of SAPs on the microbial activity of soils is described. New trends in the search for environmentally friendly SAPs made of modified biopolymers and waste materials are presented, which not only increase yields, but also ensure sustainable agro-environmental development. [ABSTRACT FROM AUTHOR]

To investigate the effect of soil additives in reducing the effect of water deficit stress on sugar beet, an experiment was performed as a combined analysis in two regions based on randomized complete block design with four replications. Experimental treatments were location factor at two levels of Miandoab and Malekan, water deficit stress factor at three levels of 50 mm (lack of stress), 110 mm (moderate stress) and 170 mm (severe stress) evaporation from class A evaporation pan and soil additive factor at four levels of control (no soil additives), superabsorbent, mycorrhiza and livestock manure. In the present study, the use of soil additive treatments in both regions were able to improve the yield of pure sugar compared to control. In irrigation treatment after 170 mm of evaporation, the highest leaf area index (3.28), relative leaf water content (65.96%), shoot dry weight (3.45 t ha-1 ), root yield (49.48 t ha-1 ), gross sugar yield (9.73 t ha-1 ) and pure sugar yield (8.32 t ha-1 ) were obtained by mycorrhiza application and sugar content (20.48%) and pure sugar percent (17.11%) were obtained in control and superabsorbent application, respectively. In water deficit stress, application of mycorrhiza and superabsorbent were able to significantly increase the yield of pure sugar compared to the control. Due to the fact that sugar beet is exposed to different periods of water deficit stress in the tested areas, the use of mycorrhiza and superabsorbent can be a suitable method to reduce the effect of water deficit stress in sugar beet. [ABSTRACT FROM AUTHOR]

In the present study, a hybrid chitosan‐alginate superabsorbent is prepared using maleic acid as a cross‐linker and acrylamide as a grafting agent using the free radical mechanism. The composite hydrogel shows good swelling capacity along with hemocompatibility and biocompatibility and hence it is utilized as a drug delivery device. The characterization techniques including x‐ray diffraction, Fourier transform infrared, x‐ray photoelectron spectroscopy, and thermal analysis indicate the successful synthesis of stable hydrogel with rich functionalities. Metformin hydrochloride is used as a model drug which is used to treat diabetes. The drug encapsulation is done using the swelling diffusion method after the synthesis of hydrogel. The release of metformin from the drug‐loaded hydrogel at physiological pH highlights the role of non‐covalent interactions between the drug and hydrogel. In vitro release studies of Metformin from the drug‐loaded hydrogel show higher release profiles at intestinal pH (7.4) compared to stomach pH (1.2). The observed cumulative release is 82.71% at pH 7.4 and 45.67% at pH 1.2 after 10 h. Brunauer–Emmett–Teller analysis reveals the effect of surface area, pore size, and pore volume of hydrogel on the drug release. The drug release from the hybrid chitosan‐alginate hydrogel is found to be more sustained in comparison to the pure chitosan hydrogel. For the present drug delivery system, the swelling‐controlled release is found to be more dominating than the pH‐controlled release. The synthesized hydrogel can be successfully employed as a potential drug delivery system for controlled drug delivery. [ABSTRACT FROM AUTHOR]

This study investigates the internal curing effects of milkweed fibres (MW) in Portland cement mixes, exploring various dosage levels and pre-treatment methods. The study first assessed the impact of MW fibres on the effective water-to-cement (w/c) ratio through rheological measurements, enabling accurate comparisons of samples with identical effective w/c ratios. Both MW fibre pre-treatments and dosages were found to impact the effective w/c ratio in the mixes, leading to the categorization of MW fibre-incorporated samples into three groups based on their effective w/c ratio. In the subsequent phase, the internal curing effect and hydration characteristics of cementitious mixes were evaluated with varying dosages of MW fibres. Optimal internal curing performance was achieved with 0.1% pre-treated MW fibres compared to 0.2%, resulting in up to a 17% improvement in the degree of hydration compared to the reference sample with the same effective w/c ratio. This showed the adverse effect of higher percentage due to the reduction in the free water availability and higher leaching of extractives, which further intensified the hindrance of the hydration process. Furthermore, microstructure analyses, including TGA/DTG, XRD, and SEM-EDS, of cementitious mixes incorporating MW fibres confirmed that the inclusion of 0.1% hybrid and hydrothermally-treated MW fibres resulted in a higher formation of hydration products. This is achieved by providing an adequate amount of free water for the initial reaction of cement hydration and entrained water in the lumen for the subsequent internal curing. These findings show the effectiveness and suitability of using pre-treated MW fibres for internal curing applications, as validated by the comprehensive analyses conducted in this study.

Foreign practice of oil production in high-water-cut conditions suggests using the technology of injection of preformed particle gel (PPG) suspension into injection wells. After swelling, the polymer particles become elastic and are able to penetrate through highly permeable watered intervals into the remote reservoir zone, forming a polymer “plug”. Thus far, the domestic experience of application of this technology boiled down to testing foreign compounds. We have looked into the possibilities of PPG technology application in geological and technological conditions of high-water-cut fields of Perm Krai. The paper proposes PPG reagents effective in low-temperature reservoirs (20-35 °С) and at relatively high salinity of formation water (more than 200 g/l). The world experience of PPG technology application was analyzed to identify the principal scheme of reagent injection, to establish variants of sequence of injection of PPG particles of different sizes, as well as the possibility of regulating the morphological characteristics of polymer gel particles during synthesis depending on the porosity and permeability of the reservoir. A prerequisite for the technology is the ability to remove PPG particles after treatment from the bottom-hole zone of the formation; for this purpose, tests were carried out on a breaker compound based on sodium persulfate with synergizing additives. PPG technology is effective in reservoirs with high permeability heterogeneity. Two types of high-water-cut production facilities potentially promising for PPG realization have been identified for oil fields of Perm Krai. The first type includes carbonate Tournaisian-Famennian reservoirs with pronounced macrofracturing, in which the PPGs are used for colmatation of flushed large fractures. The second type is terrigenous Visean deposits with increased oil viscosity from 5 to 100 mPa∙s and high permeability of reservoirs (> 0.5 μm2). For both types of reservoirs, areas have been selected that are promising for the implementation of PPG technology.

Background: Cassava waste pulp from the tapioca industry is abundant in Indonesia. However, there have been few Indonesian or international papers describing research on the possible use of cassava waste pulp as a superabsorbent after modification. The goal of this work was to increase the added value of cassava waste pulp by converting it into a superabsorbent. This conversion was carried out by a graft copolymerization of cassava waste pulp using acrylamide, ammonium persulfate, and N,Nâ²-methylene-bisacrylamide as a monomer, an initiator, and a crosslinker, respectively. The copolymerization was conducted at 70°C for 3 h and saponified with 1 M NaOH for 2 h. Results: The superabsorbent had a maximum water absorption capacity of 1,014 g/g at pH 7.3; the absorbency was affected by the salinity of the medium. The rate parameter for absorption in distilled water was 5.4 min. The formation of a superabsorbent was confirmed by FTIR spectroscopy, as the spectra exhibited all characteristic bands of both cassava waste pulp and acrylamide. Conclusion: Cassava waste pulp has a great potential to be used as a superabsorbent, which could give added value to cassava

SBA‐15 is successfully incorporated into a composite superabsorbent hydrogel polymer (SAHP) by in situ graft polymerization of acrylic acid (AA) on a carboxymethyl cellulose (CMC) backbone using SBA‐15 as a filler. The structure and properties of the SAHPs are studied in detail by means of a variety of characterization methods, including Fourier transform infrared spectroscopy, X‐ray diffraction, and field emission scanning electron microscopy. And the effects of the originating mate‐rials (such as SBA‐15, initiator, cross‐linker, ratio of CMC to AA, and neutralization of AA) and pH on the water absorption properties are discussed. The obtained results show that the introduction of SBA‐15 have significant effect on the intrinsic structure of the superabsorbent. Importantly, the composite SAHP exhibit higher thermal stability and significant swelling as well as water retention capacity. The prepared SAHP show good sensitivity to various surfactant solutions, which not only have water retention applications in agriculture but also show potential applications in the field of biomaterials. [ABSTRACT FROM AUTHOR]

The application of superabsorbents to soils and seed coatings is a pre-sowing seed treatment method that is commonly used to improve early vigor and establish stability and uniformity under water deficit conditions. To evaluate the interaction of seed coating and superabsorbent on Calotropisprocera L. (milkweed) under water deficit conditions, a greenhouse experiment was conducted. The experiment was conducted with four coating material levels (non-coated seeds and seeds coated with peat moss, vermicompost, and canola residue), four growth medium levels (soil, sand + soil, soil + 2 g superabsorbent, and soil + 4 g superabsorbent), and three field capacity regimes (25, 50%, and 100%) in a completely randomized design factorial arrangement with four replications. Reducing the field capacity from 100 to 25% led to decreased growth (shoot and root dry weights and leaf area) and chlorophyll content. The activities of SOD, CAT, APX antioxidant enzymes, and proline increased under drought stress. The use of superabsorbent polymers in growth media enhanced growth indices and chlorophyll content and decreased the activity of antioxidant enzymes and proline under water deficit conditions. The highest chlorophyll and growth indices were observed when 4 g of superabsorbent was added to the growth medium under drought stress. The application of 4 g of superabsorbent to the growth medium reduced the activity of antioxidant enzymes and proline. The use of seed coatings improved the growth indices, antioxidant enzyme activity, and chlorophyll content under drought stress. The most adaptive morphological and physiological responses to water stress were observed in the vermicompost-coated seeds. The vermicompost coating containing a superabsorbent polymer (4 g/kg soil) proved to be the best for establishing milkweed under mild (50% FC) and severe water deficits (25% FC). [ABSTRACT FROM AUTHOR]

In the era of observed climatic changes that contribute to the emergence of soil moisture deficiency, effective ways to retain and rationally manage water are being sought. One of the ways to make water available during periods without rain is the use of a superabsorbent. The aim of the study was to identify the response of two soybean cultivars (Glycine max (L.) Merrill) to different doses of a superabsorbent polymer (SAP). The effect of the SAP on seed yields, selected elements of the yield structure and the chemical composition of seeds were evaluated. The study was carried out during 2016–2018, based on a two-factor field experiment, in a split-plot design, where the dose of SAP (0, 20, 30 kgha−1) and legume cultivar (Aldana, Merlin) were the factors. The results of the research showed that SAP application significantly increased the yield of soybean, but did not affect the quantitative traits and chemical composition of seeds. Genetic factors differentiated the seed yields and chemical composition of the soybeans. A significantly higher yield was obtained for the Merlin cultivar compared to Aldana (by 31.0% on average). The Merlin cultivar accumulated more total protein in seeds, but contained significantly less crude ash and potassium compared to Aldana. [ABSTRACT FROM AUTHOR]

In this paper, we examined adsorption process of bovine serum albumin (BSA) on [p(HEMA)‐g‐CTS]/MMT ([poly(2‐hydroxyethyl methacrylate)‐graft‐chitosan]/montmorillonite) superabsorbent nanocomposite. [p(HEMA)‐g‐CTS]/MMT superabsorbent nanocomposite was synthesized via free radical polymerization. Fourier transform infrared spectroscopy (FTIR), scanning electron microscopy (SEM), and thermal gravimetric analysis (TGA) techniques, and also swelling test have been utilized for the structural characterization of the synthesized [p(HEMA)‐g‐CTS]/MMT superabsorbent nanocomposite. The influence of numerious adsorption parameters (initial BSA concentration, contact time, pH, sorbent amount, temperature, and ionic strength) on adsorption process were evaluated. Adsorption results showed that the superabsorbent nanocomposite had high affinity to BSA, and maximum adsorption capacity of [p(HEMA)‐g‐CTS]/MMT superabsorbent nanocomposite is 75.8 mg/g. The BSA adsorption results showed that the adsorption kinetics parameters was found to be suitable for the pseudo‐second‐order kinetic adsorption model and the equilibrium BSA adsorption data were explicated according to the Freundlich adsorption isotherm model. [ABSTRACT FROM AUTHOR]

Superabsorbent can be used as a carrier for urea-fertilizer which can release urea slowly and can be used as a dry soil moisturizer. The main goal of the current study was to investigate the influence of adding chitosan grafted onto acrylic acid as a superabsorbent base material on the properties and characteristics of the resulting superabsorbents. The method used to prepare the superabsorbent was the gamma irradiation technique. Acrylic acid was neutralized by adding KOH, and then chitosan was added. The mixture was put in a plastic container, followed by irradiation with gamma rays. The formed superabsorbent was washed and dried in an oven, then the dry superabsorbent was analyzed for its properties and characteristics. The results showed that superabsorbent properties such as swelling ratio (from 49.38 g/g to 49.38 g/g), water retention (0.43%-0.89% after 7 days), and urea loading (86.75% to 96.4%) were affected by the amount of chitosan added. However, adding too much chitosan can reduce the superabsorbent properties. The characterization of the superabsorbent revealed a smooth surface with a porous structure, and FTIR analysis showed that chitosan was grafted onto acrylic acid.

As commercial superabsorbent polymer (SAP) hydrogels do not possess antimicrobial activity, the bioactivity induction is a research target to increase their diverse benefits, particularly, in their bio-applications. This work reports a facile and nearly quantitative synthesis of a novel partially bio-based Schiff base modifier (an imine-amine modifying agent based on furfural) under catalyst-free and solvent-free conditions. The modifier was identified by FTIR, 1H- and 13C-NMR spectroscopies. Then, a commercial SAP was feasibly surface modified by the modifier via a facile transamidation process followed by additional modification with copper (II) acetate to form Cu-coordination complex on the gel network (Ai: intact SAP, A1: modified with Schiff base, A2: modified with coordination complex, and A3: modified with copper (II) acetate). The modification reactions were confirmed morphologically and rheologically. The free-swelling measurements in deionized water and saline media revealed that the super absorbency was well-preserved after the modification. The saline-absorbency under load (AUL, 0.3 psi) tests verified that the modified samples owned 5–17% higher AUL compared to the unmodified sample. Antibacterial measurements against two bacterial strains (S. aureus and E. coli) proved that the metal complex formation significantly induces antibacterial activity comparing to both the intact and the metal-free Schiff-base-treated SAPs. The feasible processes and/or modified products may be considered for being used in bio-medical applications such as surgical pads and wound dressings. [ABSTRACT FROM AUTHOR]

Ten different hydrogels were prepared and analyzed from the point of view of their use in soil. FT-IR spectra, morphology, swelling ability, and rheological properties were determined for their characterization and appraisal of their stability. The aim was to characterize prepared materials containing different amounts of NPK as mineral fertilizer, lignohumate as a source of organic carbon, and its combination. This study of stability was focused on utility properties in their application in soil—repeated drying/re-swelling cycles and possible freezing in winter. Lignohumate supported the water absorbency, while the addition of NPK caused a negative effect. Pore sizes decreased with NPK addition. Lignohumate incorporated into polymers resulted in a much miscellaneous structure, rich in different pores and voids of with a wide range of sizes. NPK fertilizer supported the elastic character of prepared materials, while the addition of lignohumate shifted their rheological behavior to more liquid. Both dynamic moduli decreased in time. The most stable samples appeared to contain only one fertilizer constituent (NPK or lignohumate). Repeated re-swelling resulted in an increase in elastic character, which was connected with the gradual release of fertilizers. A similar effect was observed with samples that were frozen and defrosted, except samples containing a higher amount of NPK without lignohumate. A positive effect of acrylamide on superabsorbent properties was not confirmed. [ABSTRACT FROM AUTHOR]

One of the strategies for efficiently using agricultural water resources and preserving them is to use absorbent materials such as pumice in soil. The present research aimed to evaluate the effects of different levels of pumice on soil water content and Russian olive seedling growth. For this purpose, an experiment was designed and conducted as a randomized complete block design with four treatments and three replications from 2017 to 2018 in the Khajeh Research Station. Treatments included control (no pumice), and 10%, 20%, and 30% pumice. During the experiment, the average soil moisture content was measured by TDR every 10 days. The growth characteristics of the Russian olive seedlings, including seedling height, collar diameter, and leaf area were measured. Minimum soil water content was recorded for the control treatment and then a significant increase was observed by increasing the use of pumice. In the control treatment, seedling height, collar diameter, and leaf area were 56 cm, 6.2 mm, and 108 cm², respectively, while in the 30% pumice treatment, the same characteristics were significantly increased to 105 cm, 11.4 mm, and 201 cm², respectively. So, by increasing the amount of pumice from 0 to 30%, seedling height, collar diameter, and leaf area increased by 87, 84, and 86%, respectively. Therefore, we can conclude that pumice by retaining soil water during the growing season, especially in rainfed conditions, prevents plant water-deficit stress and enhances its growth and development. [ABSTRACT FROM AUTHOR]

The problems that are often encountered in the results of the development of material modification of super absorbent polymers include water absorption ability and ability swelling which is low, limited solubility in water and organic compounds, in addition to the condition of the material that is hard and brittle and not environmentally friendly, also being difficult to decompose. These conditions can be minimized and improved through modification of monomer compounds, crosslinker, and initiator in the polymerization process. The polymerization process is carried out by the method of chemical crosslinker with crosslink agent i.e. formaldehyde in the main chain (backbone), namely polyvinyl alcohol, and daughter chains, i.e. bagasse cellulose, with the help of an initiator in the form of potassium persulfate. The results of the study showed that formation of a new functional group (C-OH stretch) at 1143.30 cm-1; (-OH) at 3461.03 cm-1; (C-O-C) at 1200.55 cm-1; (C=O) at 1529.86 cm-1. The highest absorption capacity reached 746.49% in the sample with 0.8 gram of initiator and crosslink 0.8 mL. Mark Swelling the highest was obtained under acidic conditions, namely pH 6 with a value of 358.30. The surface morphology of the superabsorbent, which is a dense, strong and elastic surface, is formed with pores ±11.75 nm. The surface change proves that the grafting process and interfacial interactions of two materials are going well. [ABSTRACT FROM AUTHOR]

Scarcity of water is a substantial impediment to the growth and yield of crop species. In this study, free-radical copolymerization was used to tailor novel formulations of superabsorbent nanocomposites (SANCs). The prepared SANCs were characterized using FT-IR spectra, SEM micrograph, TGA and X-Ray diffraction. Following SANC preparation, the swelling behavior was examined. Also, SANC's soil burial degradation and water retention were investigated. A pot trial was performed to examine the growth performance and physio-biochemical traits of Faba bean in the presence and absence of SANC under water-stress (40% FC). Water stress decreased chlorophyl and sugars contents, CAT, APX, SOD, and PPO activities. Nonetheless, water stress raised POD and GR activities, and AsA, DPPH, PMA, H2O2, MDA, and soluble proteins levels. SANC alleviated water stress by boosting Faba bean growth and physiological characteristics. SANC enhanced Chl b, carotenoids, Fv/Fm, CAT, GR and SOD, contributing to better growth of stressed Faba bean.

A series of glucose‐based degradable superabsorbent hydrogels with potential to tackle issues associated with sustainability, flooding, and drought has been designed and fabricated. These hydrophilic networks were constructed through integrating glucose as a primary building block –into cyclic oligomers and block polymers, which were combined into mechanically‐interlocked slide‐ring crosslinked materials. Crosslinking of slide ring α‐cyclodextrin/poly(ethylene glycol)‐type polyrotaxanes with acid‐functionalized ABA triblock copolymers comprised of mercaptopropionic acid‐functionalized poly(glucose carbonate (ethyl propargyl carbonate))‐b‐poly(ethylene glycol)‐b‐mercaptopropionic acid‐functionalized poly(glucose carbonate (ethyl propargyl carbonate)), afforded degradable superabsorbent hydrogels through establishment of chemically‐labile ester linkages, in addition to glycosidic and carbonate groups of the polymer precursors. With an emphasis on development of fundamental synthetic design strategies to achieve high‐performance superabsorbent hydrogels that could behave as robust materials, which are derived from natural components and exhibit hydrolytic degradability, effort went into optimization of the composition, structure, and topology leading to water uptake capacities >30× by mass. Investigations of composition‐structure‐topology‐morphology effects on properties as a function of variations of PEG main chain length, degree of α‐cyclodextrin coverage, and concentration of pre‐gel solution, indicated that the slide‐ring polymer and triblock copolymer networks feature high water uptake, tunable mechanical properties, and sustainability with construction from renewable natural products and in‐built degradability. [ABSTRACT FROM AUTHOR]

Due to their unique properties, hydrogels can be used in many areas of life and science. The main purpose of this work was to present the possibility of using hydrogels as a kind of fire retardant material itself and as a medium in fire retardant materials used, among others, as the extinguishing agents for fires and the suppression agents for the self-ignition of coal in mines (where their low viscosity and high ability to penetration of the protected material is used), protective layers in fabrics and the so-called robot skin (most often applied in the layer-by-layer system), filling in the fire retardant window panels (mostly hybrid hydrogels or hydrogel copolymers are used) and protective emulsions of the wooden elements used in construction and furniture joinery (mainly in combination with silicate and phosphate derivatives). In the presented applications, hydrogels can be used alone, e.g. due to the large water capacity and at the same time the possibility of dilution, or in combination with fire retardants, what very often allows for the multiplication of the extinguishing or fire retardant effect. Due to the multitude of available studies and the speed of scientific development, this review is focused mainly on publications written after 2015. [ABSTRACT FROM AUTHOR]

ABSTRACT The phenomenon of desertification has a negative impact on the national economy of any country and may usually be obtained for many reasons such as the removal of agricultural land, depletion of soil, overgrazing, methods of poor irrigation, high temperature, and the lack of rainfall. The following paper tackles solving the problem of the lack of rainfall through the use of chemical methods such as preparing sodium polyacrylate and improving its properties by means of adding bentonite and thus obtaining a new and improved water absorption compound. The study concludes that the suitable range of bentonite ratio that is between (0 - 20 wt %) ensures water absorption from 1340 gg - 1 to 1500gg – 1 and thus the researcher confirms that the cross-linked of the compound will not be changed and the absorption of water will be higher. The presence of bentonite with polymer at a perfect percentage contributes to the reorganization of the distribution of the granular size of the polymer sodium polyacrylate—a matter that is reflected on the growing of its ability to absorb water and thus becoming a suitable compound in the treatment of desertification.

Superabsorbent hydrogels are polymers with a 3D network that have attracted the attention of scientists and industrialists because of their fantastic ability to absorb and retain water and aqueous solutions. The most widely used and commercially available superabsorbent hydrogels are synthetic K-acrylate materials. In this novel study, superabsorbent hydrogels have been developed using natural ingredients to have more biodegradable properties. Superabsorbent hydrogels were synthesized from acrylic acid, cassava starch, and chitosan using the γ-irradiation method under different experimental conditions. The γ-irradiation technique was chosen to produce hydrogels free of residues that may remain when chemical crosslinkers are used. The effects of irradiation dose, acrylic acid composition, and the amount of cassava starch and chitosan on the characteristics of produced hydrogels were analyzed. The resulting polymers were further characterized by fourier transform infrared spectroscopy (FTIR) and scanning electron microscope (SEM) to evaluate the structure. The thermal behavior of superabsorbent products at different neutralization doses was tested with differential scanning calorimetry (DSC). FTIR data indicated that the grafting reaction was successfully implemented in this work. SEM analysis showed that the hydrogel produced from this study was porous and there was a reduction in pore size with the addition of starch and chitosan. It can be concluded that the addition of cassava starch and chitosan affects the acrylic acid-based superabsorbent properties, which are pore size, thermal behavior, gel content, antibacterial activity, and swelling capacity in water, salt, and urea solutions. The best hydrogel was obtained by adding 0.25 g of cassava starch and 0.25 g of chitosan, using 50 % acrylic acid neutralization and 5 kGy γ-irradiation doses. The graft polymers possess the maximum swelling capacity of 670 g/g for distilled water, 520 g/g for NaCl solution, and 767 g/g for urea solution (relative to the dry weight). These products were sterile from Escherichia coli bacteria and had the potential to be applied as superabsorbent resins for various fields.

The gamma radiation technique is simple and time-saving for the synthesis of pure hydrogels. The present work focuses on synthesizing and characterizing Diallyldimethylammonium Chloride-Acrylic acid-(3-Acrylamidopropyl) trimethylammonium Chloride (DADMAC-AAc-APTAC) superabsorbent hydrogels. The hydrogels were synthesized by applying gamma radiation of different doses (2 kGy to 30 kGy) to two different compositions of monomers. The equilibrium swelling was found to be 33483.48% of dried gel for a 1:0.5:1 composition ratio of monomers at a 2 kGy radiation dose. Therefore, on the basis of equilibrium swelling, 2 kGy is the optimum radiation dose for synthesizing the hydrogel. Fourier transform infrared (FTIR), nuclear magnetic resonance (NMR) spectroscopy, and X-ray diffraction (XRD) characterization techniques were used to analyze and confirm the structure of the hydrogel. Thermogravimetric analysis (TGA) and Scanning electron microscopy (SEM) equipped with energy dispersive spectroscopy (EDS) clearly showed the thermal stability and surface morphology of the gel. Therefore, it can be concluded that hydrogels can be used in metal adsorption, drug delivery, and other fields of study. [ABSTRACT FROM AUTHOR]

Keratin is a largely available protein that can be obtained from the ca. 3 million tons of feathers that the European poultry industry produces as a side-stream. Here, the functionalization of keratin from poultry feathers was evaluated using a one- versus two-stage process using two functionalization agents (succinic anhydride-SA and ethylene dianhydride-EDTAD). The functionalization resulted in the keratin having improved liquid swelling capacities, reaching up to 400%, 300%, and 85% increase in water, saline, and blood, respectively, compared to non-functionalized keratin. The highest swelling was obtained for samples functionalized with EDTAD (one-stage process), while the highest saline uptake was noted for samples processed with 25 wt% SA (two-stage process). Swelling kinetics modeling indicated that the water uptake by the functionalized samples takes place in two steps, and the EDTAD samples showed the highest diffusivity. It is demonstrated that the one-stage functionalization of keratin utilizing EDTAD results in better performance than two-stages, which allows for resource-saving and, thereby, protecting the environment. The results show some potential for the keratin to be utilized as liquid absorbent materials in water, saline, and blood uptake applications. Using keratin from side-streams is an advantage from a sustainability perspective over biomacromolecules that need to be extracted from virgin biomass. [ABSTRACT FROM AUTHOR]

Foreign body (FB) ingestion is a common health problem that affects children more than adults. According to gastroenterologists’ guidelines, the management of FB ingestion differs slightly between adult and children. This review aimed to compile adult and children guidelines and establish an understandable association to reveal the requirements and timing of the endoscopic procedure, which is the most effective and least complicated technique for gastrointestinal FBs. Coins, pins, and chicken and fish bones have been the most commonly ingested FBs. However, with their increasing use in recent years, large batteries with lithium)ion conversion, stronger magnets composed of rare earth metals, such as neodymium, and superabsorbent objects have become the most morbid and mortal, necessitating new management strategies. Although the approach to gastrointestinal FBs is controversial, with different treatment options available in different disciplines, many studies have demonstrated the efficacy and safety of endoscopic procedures. Many factors influence the timing of endoscopy, including the nature, size, and location of the ingested object and the patient’s clinical condition. [ABSTRACT FROM AUTHOR]

Covalently crosslinked sodium carboxymethyl cellulose (CMC)–hydroxyethyl cellulose (HEC) hydrogel films were prepared using citric acid (CA) as the crosslinking agent. Thereafter, the physically crosslinked κ-carrageenan (κ-CG) polymer was introduced into the CMC–HEC hydrogel structure, yielding κ-CG/CMC–HEC double network (DN) hydrogels. The κ-CG physical network provided sacrificial bonding, which effectively dissipated the stretching energy, resulting in an increase in the tensile modulus, tensile strength, and fracture energy of the DN hydrogels by 459%, 305%, and 398%, respectively, compared with those of the CMC–HEC single network (SN) hydrogel. The dried hydrogels exhibited excellent water absorbency with a maximum water-absorption capacity of 66 g/g in distilled water. Compared with the dried covalent SN gel, the dried DN hydrogels exhibited enhanced absorbency under load, attributed to their improved mechanical properties. The water-absorption capacities and kinetics were dependent on the size of the dried gel and the pH of the water. [ABSTRACT FROM AUTHOR]

This article aims to bring to light a relatively new strategy to ameliorate some problems that the agricultural sector faces in the current situation at a global level, such as water scarcity, drought, continuous degenerative processes of the soil or even the diseases caused by plant pests. One of the novel solutions that can be applied to balance the current situation is represented by the using of biodegradable superabsorbent polymers, due to their capacity, representing a reservoir able to store water, nutrients, or pesticides and then release them a constant flow, ensuring an optimal and beneficial ratio at the soil and plant level. They have numerous beneficial properties and advantages, being found in a multitude of fields, one of the most critical properties being represented by their biodegradability. Currently, the most "green" methods are being sought for obtaining these superabsorbents polymers to be used on a large scale and presenting a ratio of biodegradation as high as possible and no ecotoxicity after their application. [ABSTRACT FROM AUTHOR]

Over or under the application of fertilizers raises concerns about soil and environmental degradation, and the recently developed controlled application of fertilizers is the focus of addressing these concerns. In this study, we aimed to synthesize a new N,N-Dimethylacrylamide (DMAAm)—Maleic Acid (MA) – Starch (St)-based superabsorbent (p(DMAAm-co-MA-co-St) (DMSt1)) and to evaluate the suitability of controlled release fertilizers in lettuce cultivation. HCl/NaOH were used to create negative and positive surface modifications of DMSt1 and respectively, were named to be p(DMAAm-co-MA-co-Starch)/HCl (DMSt2) and p(DMAAm-co-MA-co-Starch)/NaOH (DMSt3). The finished product had a high-water absorbency and improved the soil's water retention capacity. Moreover, after the urea sorption and release studies of the synthesized superabsorbent were carried out in vitro, their effects on the development of the lettuce plant were also examined. During the application, the length, root diameter, number of leaves, chlorophyll amount and color characteristics of the lettuce were measured. It was also observed and photographed how the morphological and structural properties of lettuce were affected by applying drought stress. At the end of the drought stress, the color of the lettuce growing in pots with hydrogel was found to be greener and the chlorophyll content was higher compared to the control group. In addition, according to the results of the membrane damage index obtained from lettuce leaves, it was determined that water deficiency did not occur in the lettuce thanks to the hydrogels, and thus, no deterioration in the structure of the membranes occurred. In summary, it can be said that the newly synthesized superabsorbent has an alternative application potential in agricultural production. [ABSTRACT FROM AUTHOR]

Scarcity of water is a substantial impediment to the growth and yield of crop species. In this study, free-radical copolymerization was used to tailor novel formulations of superabsorbent nanocomposites (SANCs). The prepared SANCs were characterized using FT-IR spectra, SEM micrograph, TGA and X-Ray diffraction. Following SANC preparation, the swelling behavior was examined. Also, SANC's soil burial degradation and water retention were investigated. A pot trial was performed to examine the growth performance and physio-biochemical traits of Faba bean in the presence and absence of SANC under water-stress (40% FC). Water stress decreased chlorophyl and sugars contents, CAT, APX, SOD, and PPO activities. Nonetheless, water stress raised POD and GR activities, and AsA, DPPH, PMA, H2O2, MDA, and soluble proteins levels. SANC alleviated water stress by boosting Faba bean growth and physiological characteristics. SANC enhanced Chl b, carotenoids, Fv/Fm, CAT, GR and SOD, contributing to better growth of stressed Faba bean. [ABSTRACT FROM AUTHOR]

Increased environmental degradation and solid waste production has resulted in a higher demand for biodegradable materials based on biopolymers. Superabsorbent are three‐dimensional cross linked polymeric material that allow huge amounts of liquid to absorb. Synthetic superabsorbents (SABs) are extensively used as an absorbent of aqueous solutions for various applications, mainly as adult incontinence, feminine hygiene products etc. The major components of synthetic superabsorbents are acrylic/methacrylic acid. According to the report of US Environmental Protection Agency, the acrylamide used in the production of synthetic superabsorbent is extremely carcinogenic when exposed to people. On the other hand, A large number of synthetic Superabsorbent polymers are quite resistant to the environmental degradation process, and thus responsible for the accumulation of solid waste material. However, the presence of hazardous and undegraded content in the synthetic superabsorbents leads the designing of biopolymer based superabsorbents. These developed hybrid materials of superabsorbents are a combination of renewable raw materials and synthetic polymers. Biopolymer‐based superabsorbent has a lot of potential due to their excellent biocompatibility, biodegradability, and non‐lethal qualities. This review paper discusses the general perspective, characterization, and synthesis strategies for the production of hybrid superabsorbents. In addition, the methodologies for illustrating these superabsorbent hydrogels, as well as their prospective uses, are discussed. [ABSTRACT FROM AUTHOR]

Herein, inspired by camel humps, superabsorbent polymers (SAPs), and lotus leaves, we propose a bump-liked MPC (BPC) for profuse perspiration management. The fabrics can enable unidirectional sweat transport through the inner Janus fabric layer. The hump-like structure can store SAPs and adapt them to swelling. An external polydimethylsiloxane (PDMS)-coated layer can ensure excellent protective properties. HPC possesses an unrivalled sweat removal rate of 5.9 ml cm−2 min−1. [Display omitted] • We propose a bump-liked medical protective clothing inspired by superabsorbent polymers (SAPs), and lotus leaves. • It has excellent superior protection against external liquid intrusion, and can block water, blood, and ethanol. • It has excellent unidirectional water transport ability, and can achieve quickly sweat removal. • It has an unrivalled sweat removal rate of 5.9 ml cm−2 min−1 for effectively profuse perspiration management. Janus medical protective clothing (MPC) with asymmetric wetting properties can enhance the comfort of healthcare workers by transporting sweat from the skin to exterior surfaces. However, these textiles fail to promptly remove heavy sweat (e.g., several liters), resulting in soaked fabrics and reduced comfort. Herein, inspired by superabsorbent polymers (SAPs) and lotus leaves, we propose a bump-liked MPC (BPC) for profuse perspiration management. The fabrics can enable unidirectional sweat transport through the inner Janus fabric layer and sustained absorption of large amounts of sweat by the median layer of SAPs. The bump-liked structure can store SAPs and adapt them to swelling. An external polydimethylsiloxane (PDMS)-coated layer can effectively block water, blood, and ethanol from penetrating the skin (synthetic blood contact angle, 118°; anti-blood penetration resistance, 4.8 kPa), thereby ensuring excellent protective properties. More importantly, BPC possesses an unrivalled sweat removal rate of 5.9 ml cm−2 min−1, which is three orders of magnitude higher than the human sweat rate during high-intensity exercise. This work addresses the dual challenge of profuse perspiration management and resistance to liquid penetration, which represents a promising direction for improving the thermal-moisture comfort of medical protective clothing. [ABSTRACT FROM AUTHOR]

The study focus is the valorization of banana agriculture by products by the extraction and derivatization of cellulose and its incorporation in formulations to produce superabsorbent materials endowed with high water absorption performances. The extracted cellulose (BP) was subjected to a controlled oxidation by sodium periodate to convert it to cellulose dialdehyde (DAC) with controlled aldehyde content. The cellulosic materials were incorporated into a suspension containing acrylic acid (AA) and itaconic acid (IA) to produce composite hybrid hydrogels (SA-BP/SA-DAC) by radical chain polymerization in water, using N , N -methylene-bis-acrylamide (MBA) as a cross-linking agent and potassium persulfate (KPS) as an initiator. The prepared materials were characterized using techniques such as Fourier-transform infrared spectroscopy (FTIR), scanning electron microscopy (SEM), and rheological analysis. Additionally, the absorption and re-swelling capacities of the superabsorbent composites (SAPs) were assessed through kinetic studies in water and NaCl solution. Notably, dialdehyde cellulose (DAC), due to its low crystallinity index, hydrophilicity (attributed to aldehyde and hemiacetal functions), and high polarity, holds promise for enhancing the swelling and water retention capacity of the hydrogel. A water absorption capacity as high as 1240±60 g.g-1 was obtained for SA-DAC with a DAC content of 5 %wt. Additionally, the reusability of the SAPs was evidenced. [Display omitted] [ABSTRACT FROM AUTHOR]

The application of superabsorbents to soils and seed coatings is a pre-sowing seed treatment method that is commonly used to improve early vigor and establish stability and uniformity under water deficit conditions. To evaluate the interaction of seed coating and superabsorbent on Calotropisprocera L. (milkweed) under water deficit conditions, a greenhouse experiment was conducted. The experiment was conducted with four coating material levels (non-coated seeds and seeds coated with peat moss, vermicompost, and canola residue), four growth medium levels (soil, sand + soil, soil + 2 g superabsorbent, and soil + 4 g superabsorbent), and three field capacity regimes (25, 50%, and 100%) in a completely randomized design factorial arrangement with four replications. Reducing the field capacity from 100 to 25% led to decreased growth (shoot and root dry weights and leaf area) and chlorophyll content. The activities of SOD, CAT, APX antioxidant enzymes, and proline increased under drought stress. The use of superabsorbent polymers in growth media enhanced growth indices and chlorophyll content and decreased the activity of antioxidant enzymes and proline under water deficit conditions. The highest chlorophyll and growth indices were observed when 4 g of superabsorbent was added to the growth medium under drought stress. The application of 4 g of superabsorbent to the growth medium reduced the activity of antioxidant enzymes and proline. The use of seed coatings improved the growth indices, antioxidant enzyme activity, and chlorophyll content under drought stress. The most adaptive morphological and physiological responses to water stress were observed in the vermicompost-coated seeds. The vermicompost coating containing a superabsorbent polymer (4 g/kg soil) proved to be the best for establishing milkweed under mild (50% FC) and severe water deficits (25% FC).

Dust and fine superabsorbent polymer particles (< 150 µm) cause problems during absorbency through the gel blockage phenomenon. Hence, they are removed and considered as waste materials which can harshly raise economic and environmental issues for industries. The recycling of this class of material is of great importance. Herein, the fine acrylate-based SAP particles have been recycled using silicone-based coupling agents as reactant via IPN and crosslinking strategies to agglomerate the fine particles. The process has been conducted in three major steps: treatment solution preparation, agglomeration and moulding the SAP fines through the impregnation approach, and then pulverizing the moulded SAP. ATR-FTIR, SEM, oscillatory rheometer and compression strength analysis were employed for this study. The effect of acetone-to-water ratio, reactant type and extent on free swelling capacities in deionized water and saline solution, absorbency under load (AUL), recycling performance, elastic and loss moduli, and compression strength have been investigated. The fine SAP can be recycled up to 80% without any deteriorated properties, either swelling or mechanical; even recycling can raise the swollen gel strength under stress. The analytical investigation of recycled SAP particles reveals a well-attached porous structure that incredibly maintains its integrity in wet and dry states. The weld lines have been perfectly covered by siloxane-based IPN formation. The ability to design and tune the shape of the absorbent article with definite strength based on application makes this recycling process promising. [ABSTRACT FROM AUTHOR]

World population is increasing at an alarming rate, and crop cultivation on marginal lands has emerged as an alternate option to feed the burgeoning population. However, marginal lands are characterized by poor soil health and other undesirable characteristics resulting in low crop production and less economic returns. Interest in the application of superabsorbent polymers (SAPs) for marginal lands has been increasing. The SAPs application increases the germination percentage, seedling growth, and grain yield of different crops. Being hydrophilic in nature, SAPs can absorb and retain a huge quantity of water, and thereby enhance the water use efficiency in crops. In addition, SAPs application also showed a positive influence on soil physico-chemical properties and enhanced the retention of water and nutrients. Marginal lands are frequently subjected to abiotic stresses such as drought, heavy metals, and salinity. The application of SAPs serves as a buffer against these abiotic stresses and reduces the risk of plant damage and hence crop failure. Over the past decade, focused efforts have been undertaken on SAPs application on arable lands, especially in arid regions. However, understanding about SAPs application on marginal lands is not well understood. The present review critically discusses the potential of SAPs application to enhance the productivity of marginal lands with a major focus on crop performance under different stresses. Current challenges hindering the wide application of SAPs are also discussed. [ABSTRACT FROM AUTHOR]

This work aimed to determine the effect of biodegradable superabsorbent hydrogel based on cellulose derivatives on the growth and yield of sweet corn (Zea mays saccharata Sturt) on dry land. The design used was a completely randomized design (CRD). The applied treatments consisted of four levels of hydrogel: without hydrogel (control), 2, 4, and 6 g per plant, respectively. Each treatment was repeated six times in this experiment, yielding a total of 24 experimental pots. Each experiment pot contained 3 plants, thus all 72 plants. The results showed that the hydrogel would significantly increase soil moisture, relative water content, growth of the plant height, stem diameter, and ear cobs without corn husk. Likewise, on the length of the ear without ear cobs and wet ear weights without corn husk. As the hydrogel preserves soil moisture, allowing water to be available for the plant, it might also temporarily store soil from the water and gradually remove it into the soil. Further investigations should be performed to completely characterize the interaction between the superabsorbent hydrogel and the dry land soil. [ABSTRACT FROM AUTHOR]