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Traditional adhesive hydrogels perform well in tissue adhesion but they fail to prevent postoperative tissue adhesion. To address this challenge, a biodegradable Janus adhesive hydrogel (J-AH) was designed and fabricated by the assembly of three different functional layers including anti-adhesive layer, reinforceable layer, and wet tissue adhesive layer. Each layer of J-AH serves a specific function: the top zwitterionic polymeric anti-adhesive layer shows superior resistance to cell/protein and tissue adhesion; the middle poly(vinyl alcohol)/tannic acid reinforceable matrix layer endows the hydrogel with good mechanical toughness of ∼2.700 MJ/m3; the bottom poly(acrylic acid)/polyethyleneimine adhesive layer imparts tough adhesion (∼382.93 J/m2 of interfacial toughness) to wet tissues. In the rat liver and femoral injury models, J-AH could firmly adhere to the bleeding tissues to seal the wounds and exhibit impressive hemostatic efficiency. Moreover, in the in vivo adhesion/anti-adhesion assay of J-AH between the defected cecum and peritoneal walls, the top anti-adhesive layer can effectively inhibit undesired postoperative abdominal adhesion and inflammatory reaction. Therefore, this research may present a new strategy for the design of advanced bio-absorbable Janus adhesive hydrogels with multi-functions including tissue adhesion, anti-postoperative adhesion and biodegradation. Despite many adhesive hydrogels with tough tissue adhesion capability have been reported, their proclivity for undesired postoperative adhesion remains a serious problem. The postoperative adhesion may lead to major complications and even endanger the lives of patients. The injectable hydrogels can cover the irregular wound and suppress the formation of postoperative adhesion. However, due to the lack of adhesive properties with tissue, it is difficult for the hydrogels to maintain on the wound surface, resulting in poor anti-postoperative adhesion effect. Herein, we design a Janus adhesive hydrogel (J-AH). J-AH integrates together robust wet tissue adhesion and anti-postoperative adhesion. Therefore, this research may present a new strategy for the design of advanced bio-absorbable Janus adhesive hydrogels. [Display omitted] [ABSTRACT FROM AUTHOR]

Balancing biocompatibility and drug-loading efficiency in nanoparticles presents a significant challenge. In this study, we describe the facile fabrication of poly (acrylic acid)-mesoporous zinc phosphate/polydopamine (PAA-mZnP/PDA) Janus nanoparticles (JNPs). The PDA half-shell itself can serve as a photothermal agent for photothermal therapy (PTT), as well as to offers sites for polyethylene glycol (PEG) to enhance biocompatibility. Concurrently, the mesoporous ZnP core allows high loading of doxorubicin (DOX) for chemotherapy and the Cy5.5 dye for fluorescence imaging. The resultant PAA-mZnP/PDA-PEG JNPs exhibit exceptional biocompatibility, efficient drug loading (0.5 mg DOX/1 mg JNPs), and dual pH/NIR-responsive drug release properties. We demonstrate the JNPs' satisfactory anti-cancer efficacy, highlighting the synergistic effects of chemotherapy and PTT. Furthermore, the potential for synergistic fluorescence imaging-guided chemo-phototherapy in cancer treatment is illustrated. Thus, this work exemplifies the development of biosafe, multifunctional JNPs for advanced applications in cancer theranostics. Facile fabrication of monodispersed nanomedicine with multi-cancer killing modalities organically integrated is nontrivial and becomes more challenging under the biocompatibility requirement that is necessary for the practical applications of nanomedicines. In this study, we creatively designed PAA-mZnP/PDA JNPs and fabricated them under mild conditions. Our method reliably yields uniform JNPs with excellent monodispersity. To maximize functionalities, we achieve fourfold advantages including efficient drug/fluorescent dye loading, PTT, pH/NIR dual-responsive properties, and optimal biocompatibility. The as-fabricated JNPs exhibit satisfactory anti-cancer performance both in vitro and in vivo , and demonstrate the potential of JNPs in fluorescence imaging-guided synergistic cancer chemo-phototherapy. Overall, our research establishes a pathway in versatile inorganic/polymer JNPs for enhanced cancer diagnosis and therapy. [Display omitted] [ABSTRACT FROM AUTHOR]

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Four-dimensional (4D) printing unlocks new potentials for personalized biomedical implantation, but still with hurdles of lacking suitable materials. Herein, we demonstrate a bioresorbable shape memory elastomer (SME) with high elasticity at both below and above its phase transition temperature (T trans). This SME can be digital light 3D printed by co-polymerizing glycerol dodecanoate acrylate prepolymer (pre-PGDA) with acrylic acid monomer to form crosslinked Poly(glycerol dodecanoate acrylate) (PGDA)-Polyacrylic acid (PAA), or PGDA-PAA network. The printed complex, free-standing 3D structures with high-resolution features exhibit shape programming properties at a physiological temperature. By tuning the pre-PGDA weight ratios between 55 wt% and 70 wt%, T trans varies between 39.2 and 47.2 ℃ while Young's moduli (E) range 40–170 MPa below T trans with fractural strain (ε f) of 170 %-200 %. Above T trans , E drops to 1–1.82 MPa which is close to those of soft tissue. Strikingly, ε f of 130–180 % is still maintained. In vitro biocompatibility test on the material shows > 90 % cell proliferation and great cell attachment. In vivo vascular grafting trials underline the geometrical and mechanical adaptability of these 4D printed constructs in regenerating the aorta tissue. Biodegradation of the implants shows the possibility of their full replacement by natural tissue over time. To highlight its potential for personalized medicine, a patient-specific left atrial appendage (LAA) occluder was printed and implanted endovascularly into an in vitro heart model. 4D printed shape-memory elastomer (SME) implants particularly designed and manufactured for a patient are greatly sought-after in minimally invasive surgery (MIS). Traditional shape-memory polymers used in these implants often suffer from issues like unsuitable transition temperatures, poor biocompatibility, limited 3D design complexity, and low toughness, making them unsuitable for MIS. Our new SME, with an adjustable transition temperature and enhanced toughness, is both biocompatible and naturally degradable, particularly in cardiovascular contexts. This allows implants, like biomedical scaffolds, to be programmed at room temperature and then adapt to the body's physiological conditions post-implantation. Our studies, including in vivo vascular grafts and in vitro device implantation, highlight the SME's effectiveness in aortic tissue regeneration and its promising applications in MIS. [Display omitted] [ABSTRACT FROM AUTHOR]

The management of chronic diabetic wounds is a complex issue that requires wound repair, regulation of inflammatory levels, and intervention to prevent bacterial infection. To address this issue, we developed a multifunctional photothermally responsive hydrogel (PAG-CuS) as an effective platform for managing the entire wound-healing process, including promoting wound healing, providing anti-inflammatory therapy, and performing photothermal sterilization. Constructed through copolymerization of acrylic acid (AA), methacrylic anhydride-modified gelatin (GelMA), and lipoic acid sodium (LAS) coated copper sulfide nanoparticles (CuS@LAS), PAG-CuS possessed a porous three-dimensional structure that promoted cell adhesion and had a substantial water-holding capacity. Additionally, the internal CuS@LAS not only conferred photothermal antibacterial properties to the hydrogel but also served as physical cross-linking agents, thus enhancing its mechanical strength. Under the NIR-induced photothermal effect, the porous hydrogel liberates CuS@LAS, and later CuS@LAS expels LAS via micelle deassembly to eliminate intracellular ROS. This results in the down-regulation of MMP-9 expression, promoting ECM production and facilitating wound healing. Meanwhile, the release of Cu2+ from PAG-CuS could enhance CD31 expression in endothelial cells, promoting microvessel formation, which is crucial for wound healing. In the diabetic wound model of GK rats, the PAG-CuS hydrogel reduced ROS levels, increased microvessel count, improved epithelialization, and enhanced wound healing. Therefore, this versatile photothermal hydrogel has the potential to be applied in sterilization, scavenging free radicals, and promoting angiogenesis, making it an effective and comprehensive solution to manage the challenges of diabetic wounds. Assessment of functional recovery and timely adjustment of treatment strategy is critical in the management of chronic diabetic wounds. In this work, we prepared PAG-CuS composite hydrogels by integrating in situ reduction, chemical crosslinking, and nanoenhancement techniques. The near-infrared light-induced photothermal effect of PAG-CuS gel rapidly kills bacteria at the lesion site, and the generated heat simultaneously promotes the multilevel release of LAS from the gel, which could regulate the levels of ROS and MMP-9 to promote extracellular matrix formation. In addition, the Cu2+ released from the gel can promote the formation of blood vessels to improve blood oxygenation. Therefore, this project proposes a synergistic solution to realize the whole process of management to accelerate chronic diabetic wound healing. [Display omitted] [ABSTRACT FROM AUTHOR]

[Display omitted] Colored wastewater discharge from several industries, including paper, cosmetics, leather, dying, and textile industries, is a significant environmental management issue, especially in developing countries. Copolymerization of acrylic acid (AAc) as well as gelatin (Gltn) was performed in different compositions and crosslinked utilizing gamma irradiation to form Gltn/AAc hydrogel. EDTA has modified the hydrogel to improve adsorption properties. The effect of irradiation dose, the composition of Gltn-AAc, EDTA content, and AAc content on gel percentage was studied. The swelling behavior were studied as a time function. The prepared hydrogels' surface morphologies and structure were confirmed with FTIR, SEM, as well as XRD. Modified hydrogel used in batch adsorption was studied to remove anionic and cationic dyes, namely methyl orange (MO) and methylene blue (MB), from simulated wastewater. The parameters of adsorption, like pH, time, and initial metals concentration, were studied. The removal of MB dye by modified Gltn/AAc/EDTA hydrogel was found to be greater than that of MO dye. [ABSTRACT FROM AUTHOR]

Biodegradable hydrogels are growing in demand to enable the delivery of biomolecules (e.g. growth factors) for regenerative medicine. This research investigated the resorption of an oligourethane/polyacrylic acid hydrogel, a biodegradable hydrogel which supports tissue regeneration. The Arrhenius model was used to characterize the resorption of the polymeric gels in relevant in vitro conditions, and the Flory-Rehner equation was used to correlate the volumetric swelling ratio with the extent of degradation. The study found that the swelling rate of the hydrogel follows the Arrhenius model at elevated temperatures, estimating degradation time in saline solution at 37°C to be between 5 and 13 months, serving as a preliminary approximation of degradation in vivo. The degradation products had low cytotoxicity towards endothelial cells, and the hydrogel supported stromal cell proliferation. Additionally, the hydrogels were able to release growth factors and maintain the biomolecules' bioactivity towards cell proliferation. The study of the vascular endothelial growth factor (VEGF) release from the hydrogel used a diffusion process model, showing that the electrostatic attraction between VEGF and the anionic hydrogel allowed for controlled and sustained VEGF release over three weeks. In a rat subcutaneous implant model, a selected hydrogel with desired degradation rates exhibited minimal foreign body response and supported M2a macrophage phenotype, and vascularization. The low M1 and high M2a macrophage phenotypes within the implants were associated with tissue integration. This research supports the use of oligourethane/polyacrylic acid hydrogels as a promising material for delivering growth factors and supporting tissue regeneration. There is a need for degradable elastomeric hydrogels that can support the formation of soft tissues and minimize long-term foreign body responses. An Arrhenius model was used to estimate the relative breakdown of hydrogels, in-vitro. The results demonstrate that hydrogels made from a combination of poly(acrylic acid) and oligo-urethane diacrylates can be designed to resorb over defined periods ranging from months to years depending on the chemical formulation prescribed by the model. The hydrogel formulations also provided for different release profiles of growth factors, relevant to tissue regeneration. In-vivo , these hydrogels had minimal inflammatory effects and showed evidence of integration into the surrounding tissue. The hydrogel approach can help the field design a broader range of biomaterials for tissue regeneration. [Display omitted] [ABSTRACT FROM AUTHOR]

Although zirconia ceramics were highly versatile as dental implants, their long-term presence in the human body may slow down healing and impede cell growth in the past. To enhance the cytocompatibility of zirconia ceramics, surface activation modification was used to immobilize biopolymers such that a biomimetic environment was created. Hexamethyldisilazane thin films were deposited onto the surface of inorganic zirconia through cold plasma treatment under various power and deposition time settings to form an organosilane interface layer. Next, oxygen plasma treatment was performed to activate the free radicals on the surface. Subsequently, ultraviolet light was employed to graft and polymerize acrylic acid for generating carboxyl groups on the surface. This was followed by a condensation reaction with biopolymers (chitosan, chitosan/poly-γ-glutamic acid, and gelatin). Under a 20-min deposition time at 40 W and 150 mTorr, the thin films had a maximum graft density of 2.1 mg/cm2. MG-63 cells (human osteosarcoma cells) were employed to evaluate cell compatibility. Chitosan and chitosan/poly-γ-glutamic acid promoted the compatibility of MG-63 cells (a human osteosarcoma cell line) with zirconia ceramics, whereas gelatin reduced this compatibility. The findings confirm that cold plasma treatment and graft polymerization can promote the immobilization of biomolecules and improve the biocompatibility of zirconia ceramics. This approach can be applied to the modification of zirconia ceramic implants. [ABSTRACT FROM AUTHOR]

Based on the concept of green mines and in response to the country's call for resource conservation and environmental protection, konjac glucomannan (KGM) was combined with acrylamide (AM), acrylic acid (AA) and coal slime (SM) to prepare a new biodegradable fire prevention gel (AA-AM-KGM/SM). The experimental results show that when the KGM: AM: AA: SM was 1: 9: 6: 5, the mass percentage of cross-linker was 6.3 %, and the mass percentage of initiator was 0.5 %, the AA-AM-KGM/SM gel has the best water absorption and water retention performance. FTIR and x-ray diffraction analysis showed that the graft copolymerization took place among the components, and the amorphous structure was formed. The strong adhesive force between coal slime and KGM skeleton was observed by scanning electron microscope, which proved that the colloid has strong adsorption ability to coal slime, there are pores in the overall structure, and the elements are distributed uniformly and densely. Through the analysis of the flame retardant and anti-oxidation properties of the samples and the heat release rate and smoke release rate of the coal samples mixed with the fireproof gel, it is proved that the developed gel can effectively prevent the accumulation of heat and the generation of harmful gases during the oxidation combustion of coal, showing a certain fire extinguishing effect. The mechanism of gelation and flame retardation of the fireproofing gel was further explained by molecular dynamics simulation. Therefore, AA-AM-KGM/SM gel can effectively inhibit the oxidation of coal, and is an ideal fire-proof material. • Biodegradable coal slime composite gel was prepared. • Analysis of product formation process by reaction. • Performance enhancement and structure control of fire prevention and extinguishing gel. • The mechanism of gelation and flame retardation was explained at molecular level. • Provide a new solution for the treatment and resource utilization of coal slime. [ABSTRACT FROM AUTHOR]

Geomimetic materials (GEOMI) are composite materials based on polymer and clays, able to imitate structural and functional properties of soils, including their structure, cationic exchange capability (CEC), water uptake capability (WUC), pH buffering ability, immobilizing of substances, among other. Because they can be used to develop of fertilizer slow-release systems, they have been identified as a novel approach to advance toward a most sustainable agriculture. The aim of this work was to study the effect of GEOMI on the plant growth in degraded soils. For this, GEOMI-1.0 was synthesized using poly(acrylic acid) as model of humic substances and bentonite modified with trichlorovinylsilane as mineral fraction model. Materials were characterized by different techniques. GEOMI-1.0 showed a hybrid, homogeneous, and amorphous structure. In addition, it was thermally stable at below ⁓200 °C with a Tg about 49.3 °C, showed a high WUC (⁓1384 g of water per 100 g of material). Likewise, it was verified that GEOMI-1.0 can decreases the pH values and increases the CEC of degraded soils depending on the added amount of geomaterial; but also, the electric conductivity values showed no dependence on the added amount of GEOMI-1.0. By correlation analysis, an exponential dependence of CEC was observed respect to pH changes, the relative amount added of GEOMI-1.0 and the initial CEC. Finally, using Brachiaria Brizantha cv. Marandú as plant model, the increase in the biomass content of roots and leaves, and the number of germinated seeds, were observed when GEOMI-1.0 was used for restoration of in-lab degraded soils. [Display omitted] • Geomimetic composite materials (GEOMI) can mimic functional properties of soils. • GEOMI was synthesized using PAA as humic substance model and bentonite. • Modified bentonite is obtained by insertion of polymerizable double bonds. • GEOMI can be used to improve the pH and CEC of degraded soils. • Geomimetic materials showed that they can be used for restoration of degraded soils. [ABSTRACT FROM AUTHOR]

The compatibility of polyorganylsiloxanes and high-molecular polymers used as emulsifiers was evaluated. The surface and bulk properties of the studied compounds were evaluated using the solubility parameters (6). It is shown that the copolymers of acrylic acid compound - polyacrylamide and hydrolyzed polyacrylamide, as well as polyvinyl alcohol without residual acetate groups in the macromolecule have the highest degree of incompatibility with polyorganylsiloxanes. It was established that the presence of residual acetate groups in the macromolecule of polyvinyl alcohol leads to an increase in the degree of compatibility of polymers. The calculated data on the fractions of solubility parameters and cohesive energy of polyorganylsiloxanes and emulsifying polymers are presented. The contributions of the components of polymers cohesive energy due to the fractions of dispersion interaction cw, dipole-dipole interaction add, and hydrogen bonding ah, as well as their influence on the degree of solubility of the polymer - emulsifier system, are shown. The choice of polyvinyl alcohol with residual acetate groups as an emulsifier for polyorganylsiloxanes is theoretically substantiated based on the concept of the solubility parameter as a measure of the affinity of the system components. The developed approach to assessing the compatibility of the polymer - emulsifier system is of practical importance for the creation of polymer compositions in the finishing works. [ABSTRACT FROM AUTHOR]

To compare the chelation effect on dentin-root microhardness and surface topography between 17% Ethylenediaminetetraacetic acid (EDTA), a commonly used chelating agent, and a potential chelating agent 25% copolymer of acrylic acid and maleic acid (Poly (AA-co-MA). Eleven extracted, well-preserved maxillary incisors were used. After the routine procedure of endodontic instrumentation, the roots were longitudinally split, dividing them into two halves. The samples were randomly divided into three groups of seven each (n=7). Group one was subjected to 17% EDTA. Group two was subjected to 25% Poly (AA-co-MA). Group 3 was used as a control group and treated only with saline. The chelating agents and saline were applied in a standardized method. The microhardness was evaluated using the Vickers Hardness test which was applied in three different spots on every half tooth. The surface topography was evaluated under Scanning Electronic Microscope. Paired t-test and Post Hoc tests with analysis of variance (ANOVA) were used to estimate the impact of the chelating agents on the dentin-root microhardness and to compare the two agents. A significant difference in the microhardness was observed within Group 1 and Group 2 (before/after) (p<0.05), but no significant difference was seen between Groups 1 and 2 (p>0.05). A scanning electron microscope revealed the clear impact of EDTA and Poly (AA-co-MA) in the removal of the smear layer compared with saline. Within the limitations of this study, it is concluded that 25% Poly (AA-co-MA) can be used as a chelating agent. It has an equal effect to 17% Ethylenediaminetetraacetic acid (EDTA) in reducing the dentin-root microhardness. [ABSTRACT FROM AUTHOR]

Tough hydrogel adhesives that consist of a robust gel network and can strongly adhere to wet tissues have shown great promise as the next generation of bioadhesives. While a variety of chemistries can be utilized to construct the tough gel network, the covalent conjugation methods for tissue adhesion are still limited. Here we report, for the first time, the use of side product-free amine-thiolactone chemistry which initiates a double crosslinking adhesion mechanism to develop tough gel adhesives. Thiolactone groups can conjugate with tissue-surface amines via a ring-opening reaction. The resultant thiol end groups can be further crosslinked into disulfide linkages, enabling the formation of a robust and stable adhesion layer. The thiolactone-bearing tough hydrogel composed of methacrylate-modified gelatin, acrylic acid, and thiolacone acrylamide exhibited good biocompatibility and mechanical properties, and strong adhesion to various types of engineering solids and tissues. We also demonstrated its ability to function as a tissue sealant and drug depot. The novel adhesion mechanism will diversify future design of bioadhesives for hemostasis, drug delivery, tissue repair, and other applications. Tough hydrogel adhesives with excellent tissue-adhesive and mechanical properties have demonstrated tremendous promise for hemostasis, tissue repair, and drug delivery applications. However, the covalent chemistry for tissue adhesion has been limited, which narrows the choice of materials for the design of bioadhesives and may pose a safety concern. Here, for the first time, we report the use of side product-free amine-thiolactone chemistry, which involves a double crosslinking adhesion mechanism, for developing tough hydrogel adhesives. We demonstrate that thiolactone-bearing tough hydrogels exhibit favorable biocompatibility and mechanical properties, and superior adhesion to both engineering solids and tissues. Our new adhesion technology will greatly facilitate future development of advanced bioadhesives for numerous biomedical applications. [Display omitted] [ABSTRACT FROM AUTHOR]

Fenugreek microgreens are prized for their quality, palatability, and nutritional contribution to functional foods. The present study investigated metabolomic profiling of the fenugreek microgreens and their substantial bioactive potential, including antioxidant, antibacterial, and combatting bacterial biofilms. Phytochemical screening revealed higher phenolic content in ethanol extract (54.0 ± 2.4 mg GAE g−1), and methanol extract was found to have elevated flavonoid and tannin content (68.3 ± 1.4 mg QUE g−1, 61.7 ± 1.1 mg TAE g−1). The methanol extract exhibited antioxidant potential by scavenging ABTS (75.5%, IC 50 :44.49 μg mL−1), DPPH (80.1%, IC 50 :3.85 μg mL−1) and H 2 O 2 (59.3%, IC 50 :59.3 μg mL−1) radicals, with a higher total antioxidant capacity (TAC) (90.6%). The ethyl acetate extract displayed effective antibacterial activity against Aeromonas hydrophila , Pseudomonas aeruginosa , and Staphylococcus aureus (19.75, 20.70, and 24.4 mm). Furthermore, the MICs of the ethyl acetate extract exhibited significant antibiofilm activity, with a percentage inhibition of 62.3%, 63.5%, and 70.4% against the tested pathogens. Microscopic observations and quantitative assays confirm the antibiofilm efficacy of ethyl acetate MIC against the tested pathogens. GC-MS and FT-IR spectroscopy were employed to determine the chemical compositions and profiling bioactive compounds of the extracts. The detected compounds such as 1-nonadecene, tetracosane, and eicosane, were linked to the observed antioxidant activity. Additionally, 1,2-benzene dicarboxylic acid, diethyl ester, 2-hydroxy propanoic acid, and 2-propenoic acid tridecyl ester hold antibacterial properties. This metabolomic exploration corroborates the biological attributes of fenugreek microgreens, highlighting their potential as a sustainable source of valuable nutraceutical bioactive compounds. The present study paves the way for future investigations to comprehensively explore the potential of fenugreek microgreens as a functional food source while necessitating clinical trials to validate these in vitro findings. [Display omitted] • Fenugreek microgreens (FGM) has higher phytochemicals, including phenols, flavonoids, and tannins. • Metabolomic analysis provided a comprehensive profile of the bioactive compounds present in FGM. • Methanolic extract shows better antioxidant activity by scavenging ABTS, DPPH and H 2 O 2 radicals. • FGM extracts exhibits antibacterial activity against Aeromonas hydrophila , Pseudomonas aeruginosa , and Staphylococcus aureus. • FGM shows better biofilm inhibitory potential against the tested pathogens. [ABSTRACT FROM AUTHOR]

[Display omitted] • The photo-catalytic mechanism of γ-butyrolactones from styrene and acrylic acidwas elaborated based on DFT calculations. • The cyclic mechanisms of NMA*BF 4 and PhSSPh have been investigated with DFT. • The ρ ele and ρ hole have been applied in the system to assess the photo-excitation process. The reaction mechanisms of γ-butyrolactones through electrophilic addition reactions between styrene and acrylic acid, catalyzed by the 9-mesityl-10-methylacridinium ion (NMA*BF 4) and diphenyl disulfide (PhSSPh) under 450 nm visible-light, were investigated by employing M06-2X-D3/ma-def2SVP method and basis set. In this study, the SMD model was taken to simulate the solvent effect of dichloromethane. The photocatalyst NMA absorbs the energy of photons and becomes an excited state, capturing an electron from styrene; this leads to an electrophilic addition reaction happened between the obtained styrene cationic radical and acrylic acid anion (or acrylic acid molecule); finally, an intramolecular ring-closure process and H-shift process result in the formation of the final product. The computational results point out that the electrophilic reaction is an exothermic process; and the optimal path for ring-closure reaction and H-shift reaction has Gibbs free energy barriers of 11.10 and 9.94 kcal/mol, respectively. In particular, the recycling of the photo-catalyst NMA and cocatalyst PhSSPh has also been discussed. The ρ hole and ρ ele can reveal the charge transfer process during the photo-catalytic reaction. Results would provide valuable insights into these types of interaction and related processes. [ABSTRACT FROM AUTHOR]

Lead(II) is a potential carcinogen of heavy-metal ions (HIs). With the wide application of Pb-bearing products including lead alloy products, and new-energy lead-ion batteries, lead pollution has become a tricky problem. To solve such a difficulty, novel ultrathin MoS 2 -vinyl hybrid membranes (MVHMs) with a "spring" effect were synthesized via co-polymerization of acrylic acid, styrene and molybdenum disulfide (MoS 2) and their adsorptions for HIs were explored. The "spring" effect derived from the interaction between the tendency of the short polyacrylic acid (PAA) chain connected with MoS 2 to spread outward and the coulomb force between layers from MoS 2 (s-MoS 2), which enlarge the spacing of MoS 2 layers without changing the number of layers after membrane formation, which changes the swelling membrane to a dense membrane and reduces the original thickness from 0.5 cm to 0.011 mm in the thickness direction. The adsorption experiment revealed that these MVHMs had super adsorption performance and high selectivity for Pb2+ by comparison with other five metal ions: Cu2+, Cd2+, Ni2+, Cr3+ and Zn2+. Especially, the adsorption quantity of MVHMs for Pb2+ could approach 2468 mg/g and the maximum adsorption ratio of q e [Pb2+]/q e [Cu2+] can reach 10.909. These values were much larger than the data obtained with the adsorbents reported in the last decade. A variety of models are applied to evaluate the effect of ionic groups. It was confirmed that –COOH plays a key role in adsorption of HIs and s-MoS 2 also has a certain contribution. Conversely, ion exchange plays only a minor role during the period of adsorption process. Effective diffusion coefficient (D eff) of Pb(II) had the largest values among these metal ions. Hence, these hybrid membranes are promising adsorbents for the removal of Pb2+ from water containing various ions. [Display omitted] • An ultrathin MoS 2 -vinyl hybrid membrane was made via solution co-polymerization. • The "spring" effect from MoS 2 after membrane formation was established. • The Pb2+ adsorption capacity of MVHMs significantly surpassed current adsorbent. • Its high sorption selectivity for Pb(II) in the mixture of metal ions was tested. • These membranes showed potential use in the disposal of metal-bearing wastewater. [ABSTRACT FROM AUTHOR]

Polydopamine-acrylate (P(A-D) x) nanoparticles were blended with polyethersulfone (PES) to fabricate a high-performance hybrid ultrafiltration (UF) membrane for the separation of water from oily wastewater. In tris-alkaline buffer solution at room temperature, P(A-D) x nanoparticles were synthesized by intramolecular Michael addition of dopamine with acrylic acid (AA) monomers. Hybrid PES membranes were prepared using P(A-D) x at 0.05–0.4 wt% and characterized using various assays including Field emission scanning electron microscopy (FESEM), Thermogravimetric analysis (TGA), atomic force microscopy (AFM), Fourier transform infrared spectroscopy (FTIR), and water contact angle (WCA). The membranes showed a significant increase in hydrophilicity, water permeability, and oil rejection (R). The primary and secondary pure water fluxes of the membrane with 0.2 wt% P(A-D) 0.25 were 45% and 110.78% higher than those of neat PES membrane, respectively. For 3300 ppm oil feed solution, water flux during water/oil separation increased by 107%, while the oil rejection (R) remained at 99.08%. The surface of membrane was markedly hydrophilic, with a WCA about 40°, much lower than that of the neat PES membrane (80.67°). UF hybrid membranes also showed a remarkable reduction in oil adhesion on the membrane surface as well as superior antifouling performance for membranes containing 0.2 wt% P(A-D) 0.25 , flux recovery ratio (FRR) = 84.88 ± 3.27%, reversible fouling (R r) = 51.12 ± 1.09%, and irreversible fouling (R ir) = 15.12 ± 3.27%. In addition, the pure water flux was 446% higher than that of the unmodified membrane after five cycles (900 minutes). [Display omitted] • Polydopamine-acrylate (P(A-D) x) nanoparticles were synthesized using the intramolecular Michael addition method. • P(A-D) X NPs were used to prepare PES/P(A-D) X blend membranes using the non-solvent induced phase inversion method. • Water flux during water/oil separation increased by 107%, while the oil rejection (R) remained at 99.08%. • UF membrane displayed good long-term performance stability after five cycles (900 minutes). [ABSTRACT FROM AUTHOR]

Recycling of post-consumer materials can save natural resources and solve the waste disposal problem, but most previous studies focused on the environmental benefits of recycled products versus the products made from virgin materials. This paper analyses the environmental performance of two recycled fiber produced by waste bottle (Scenario A) and textile waste (Scenario B) based on the methodology of life cycle assessment (LCA). The method of economic allocation combine with cut-off principle is adopted to shift the environmental loads from previous to following life cycle of the recyclable waste materials. To compare with Scenario A, Scenario B reduces the environmental loads by approximately 21%-48% in the eight environmental impact categories. In Scenario B, the consumption of acrylic acid should be the key improvement factors. And the optimization of electric power is the most effective measure to improve the environmental benefits. [Display omitted] [ABSTRACT FROM AUTHOR]

Thermo-gels based on chitosan crosslinked poly(N -isopropylacrylamide) were developed as alternatives to conventional eye drops for the sustained release of ketotifen fumarate in the treatment of allergic conjunctivitis. The thermo-gelling properties of the base polymer were altered prior to crosslinking with chitosan by incorporation of the hydrophilic and hydrophobic comonomers acrylic acid and methyl methacrylate respectively. Varying amounts of chitosan were incorporated by ionic interaction to produce polyelectrolyte complexes or by carbodiimide chemistry to produce covalently crosslinked networks. The lower critical solution temperature of all the chitosan crosslinked thermo-gels produced was below the surface temperature of the eye. All the chitosan crosslinked thermo-gels were found to have greater than 80% equilibrium water contents following gelation. The method and amount of chitosan incorporation allowed for tailor-ability of material rheologic properties, with full degradation occurring over a one-to-four-day period, and tailorable rates of release of 40–60% of the loaded allergy medication ketotifen fumarate. The chitosan crosslinked thermo-gels were demonstrated to be nontoxic both in vitro and in vivo. It was demonstrated that the synthesized materials could be applied to the inferior fornix of eye, sustaining a multiple day release of ketotifen fumarate, as an alternative to conventional eyedrops. Topical eyedrops are the main treatment modality for anterior ocular conditions. However, due to the natural clearance mechanisms of the eye, topical eyedrops are well established to be largely ineffective as a method of drug delivery. Herein, we investigate a method of altering thermo-gel properties of an n-isopropylacrylamide based polymer to enable the incorporation of greater amounts of chitosan by different methods of crosslinking. By controlling the synthesis parameters, final material properties can be tailored to impart ideal spreading, retention on the eye, and the rate of degradation and drug release over several days. This work also focuses on studying the rheological properties of the chitosan crosslinked thermo-gels which has not been investigated previously. [Display omitted] [ABSTRACT FROM AUTHOR]

Oxygen-rich carbonaceous microspheres (CSs) could be facilely prepared by hydrothermally carbonizing glucose, however showed low adsorption affinity toward heavy metal ions (HMs). In this work, acrylic acid (AA) doping and alkaline soaking markedly enhanced their adsorption ability to HMs. The adsorption amounts toward the tested HMs by GS10AK were 5.1-9.1 times of those by the control CS without any modification. As proved by SEM, FTIR, XPS and zeta potential, more wrinkles appeared after doping and more carboxyl groups were formed/ activated during KOH soaking process, whereas the O contents were almost unchanged. The performance of GS10AK for HMs removal under various conditions was investigated. The adsorption best processed under pH of 4-5, and completed fast in 60 mins for Pb(II) and 120 mins for Cu(II) and Cd(II). The initial and whole adsorption conformed to the intraparticle diffusion and pseudo-second-order kinetic models, respectively. The fitted maximum adsorption capacities by Langmuir isotherm model were 1.875, 1.365 and 1.216 mmol/g for Pb(II), Cu(II) and Cd(II), respectively, which was almost linear to their polarization force constants. The adsorption would be accelerated and improved under higher temperature (testing range: 285-313 K). The copresence of Na(I), Ca(II), Fe(II) and fulvic acid negatively influenced HMs removal in various range of 0.56-62.3%. The regeneration and stable reuse of GS10AK could be realized in at least three cycles. This study suggests that GS10AK and CSs synthesized using similar method hold great potential as inexpensive and green adsorbents for remediating HMs from water matrices. [ABSTRACT FROM AUTHOR]

This study investigates the effect of chitosan and acrylate acid addition in the acrylic resin as denture material toward the number of fibroblasts and inflammatory cells including macrophages, lymphocytes, and plasma cells. This study is an experimental laboratory research. Nine Wistar rats (Rattus Novergicus) were divided into 3 groups (n= 3). Control group receiving treatment without mixture of acrylic resin (CO), group 2 acrylic resin mixture with chitosan and 1% acrylate acid (ARC1), while group 3 acrylic resin mixture with chitosan and acrylate acid 2% (ARC2). The acrylic resin plate is formed in 4 mm-sized discs with 2 mm thickness. Resin samples were implanted into subcutaneous dorsal-area of Wistar rats, then stitched. Microscopic evaluation conducted on day 7 post-implantation. Histological examination combined hematoxylin eosin staining and 400x magnification light microscope. Fibroblasts, macrophages, lymphocytes and plasma cells were counted using the Image J program. Data were analyzed using one-way ANOVA and followed by LSD test with 95% level of significance. Results revealed that fibroblasts, macrophages, lymphocytes and plasma cells count in the CO group were higher than the ARC1 and ARC2 groups. Greater concentration of chitosan and acrylate acid in the acrylic resin decreased the mean of fibroblasts, macrophages, lymphocyte and plasma cells. One-way ANOVA test presented significant differences in the fibroblasts, macrophages, lymphocytes and plasma cells count of the control and treatment groups (p<0.05). The LSD test indicated significant difference between CO and ARC2 group. We concluded that the combination of acrylic resin with chitosan and 2% acrylate acid concentration is properly perceived by rat's body tissue. [ABSTRACT FROM AUTHOR]

The aim of this study was to optimize the preparation method of polymethyl methacrylate (PMMA) denture base loaded with nano silver (NAg), to more effectively and safely impart sustainable antibacterial functions. NAg solution was synthetized and mixed with acrylic acid and methyl methyacrylate (MMA) monomer in order to prepare a new type of NAg solution (NS)/polymer methyl methacrylate denture base specimens (NS/PMMA). The surface morphology, mechanical strength, antimicrobial activity, anti-aging performance, cytotoxicity and biocompatibility of NS/PMMA denture base were evaluated in comparison with specimens fabricated using traditional NAg adding methods and NAg-free denture base. The aesthetic characteristics and mechanical strength of NS/ PMMA denture base met the clinical application requirements. Meanwhile, NS/PMMA denture base showed better antibacterial activity, anti-aging properties, no cytotoxicity and displayed exceptional biocompatibility. NS/PMMA denture base thus has great potential for clinical application. [ABSTRACT FROM AUTHOR]

The anisotropic Janus nanoparticles (JNPs) provide synergistic effects by concentrating multiple properties on a single carrier. Herein, we reported a novel and simple approach to fabricate acorn-like poly(acrylic acid)-mesoporous calcium phosphate/polydopamine (PAA-mCaP/PDA) JNPs, which were selectively functionalized with methoxy-poly(ethylene glycol)thiol (PEG-SH) on PDA domains to obtain superior stability, while the other mCaP sides served as a storage space and passage for the anti-cancer drug of doxorubicin (DOX). The unique acorn-like PAA-mCaP/PDA-PEG JNPs were utilized as novel theranostic agents for photoacoustic (PA) imaging-guided synergistic cancer chemo-phototherapy. More importantly, this synthetic strategy can be applied to synthesize various mesoporous Janus nanocarriers, paving the way toward designed synthesis of acorn-like JNPs in nanomedicine, biosensing and catalysis. The distinct acorn-like poly(acrylic acid)-mesoporous calcium phosphate/polydopamine Janus nanoparticles (PAA-mCaP/PDA JNPs) with a spherical-shaped PAA-mCaP core and PDA half-shell were fabricated for the first time. To achieve superior stability, the acorn-like PAA-mCaP/PDA JNPs were selectively functionalized with methoxy-poly(ethylene glycol)thiol (PEG-SH) on PDA domains to obtain acorn-like PAA-mCaP/PDA-PEG JNPs. The resultant acorn-like PAA-mCaP/PDA-PEG JNPs own an excellent biocompatibility, high drug-loading contents, good photothermal conversion efficiency, photoacoustic (PA) imaging capacity and pH/NIR dual-responsive properties, enabling the acorn-like JNPs to be applied for PA imaging-guided synergistic cancer chemo-phototherapy. More importantly, the synthetic approach could be extended to prepare acorn-like mesoporous inorganic substances/PDA JNPs for specific applications. [Display omitted] [ABSTRACT FROM AUTHOR]

The surface functional groups of hydrochar are crucial to its surface properties, and their contents are strongly positively correlated with the adsorption performance. In this study, acrylate-functionalized hydrochar (AHC) with varying contents of O-containing functional groups (OFGs) was synthesized via hydrothermal carbonization (HTC) of bamboo, acrylic acid and an initiator, and then deprotonated with NaOH. The AHCs were analyzed by various characterization techniques. During HTC, the higher amount of acrylic acid added led to higher carbon, oxygen and carboxyl contents, and to the larger specific surface area and pore volume of AHC. The adsorption kinetics, isotherms, thermodynamic, ionic strength and pH effects of Pb(II) on AHC were studied. Adsorption isotherms and kinetics obeyed Langmuir and pseudo-second-order models, respectively, indicating adsorption is monolayer chemical process. The adsorptive ability was well linearly related to the OFG contents of AHC. When acrylic acid was added to 25 mL during HTC, the adsorbing ability of AHC over Pb(II) reached 193.90 mg g−1. Hence, direct HTC of acrylic acid, biomass and an initiator can prepare hydrochar with controllable OFG contents, which is a prospective adsorbent for treating metal cations. [Display omitted] • Efficient hydrochar was prepared by coupled HTC and free radical polymerization. • AHC25 has abundant OFGs and a high specific surface area. • The sorption capacity for Pb(II) is linearly related to the OFG contents of hydrochar. • The inner-surface complexation was the main mechanism for Pb(II) removal by AHC25. • AHC25 exhibited high sorption capacity towards Pb(II) (193.90 mg g−1). [ABSTRACT FROM AUTHOR]

With the process of industrialization, many production fields produce high-salt organic wastewater. In this work, we have employed an electrodialysis (ED)-resin-bipolar membrane electrodialysis (BMED) mixed process to address sodium acrylate wastewater, achieving resource recovery. The influences of the initial volume ratio and applied voltage were investigated. In the ED-resin, the separation of organic compounds and pigments such as sodium acrylate and phenol was realized. The desalting rate could reach 93.1%, the energy consumption is 0.6 kWh/kg C 3 H 3 O 2 Na, and the chroma removal rate can reach 99%. In the subsequent BMED phase, we attain notable acrylic acid and base concentrations, reaching levels of 1.59 mol/L and 3.12 mol/L, with a current efficiency of 58.14% and an energy consumption of 3.28 kWh/kg NaOH. In addition, economic and environmental evaluations verify the feasibility of this process, which is indicative of its prospect of industrial application. • The mixed process is employed to resourcelize the sodium acrylate wastewater. • Optimum operation conditions were investigated to obtain high quality products. • Desalination rate of during the ED process was 93.1%. • The chroma removal rate of sodium acrylate wastewater reaches 99%. • The process cost of treating sodium acrylate wastewater was estimated. [ABSTRACT FROM AUTHOR]

The potential of invertebrates in the biodegradation of plastic polymers such as polyvinyl chloride (PVC) is receiving increasing attention. The present study is aimed to identify the gut microbiome involved in this degradation in yellow mealworms, i.e., the larvae of Tenebrio molitor Linnaeus. The egested PVC polymer experienced a dramatic reduction in both number average molecular weight (Mn) and weight average molecular weight (Mw) of 99.3% and 99.6%, respectively, whereas FTIR analysis revealed chemical alterations. Mass spectrometry analysis identified two potential degradation products: phthalic acid, di(2-propylpentyl) ester and 2-Propenoic acid, tridecyl ester. Further, we used metagenomic sequencing to elucidate the response of the gut microbiome when transitioning from bran to PVC as a food source, identifying four microorganisms actively involved in PVC degradation. Additionally, metagenomic functional analysis of the gut microbiome identified 111 key gene modules that were significantly enriched. In summary, our findings suggest that yellow mealworms adapt to PVC degradation by modifying their gut microbiome both structurally and functionally. • Yellow mealworms exhibit a capacity to sustain a certain level of growth through PVC consumption when provided PVC as their sole diet under solitarily raising conditions. • The onset of PVC degradation was substantiated by alterations in PVC's chemical structure. • Two potential degradation products in the frass were recognized. • The dietary effect of PVC led to changes in the expression of intestinal flora and its functional genes in yellow mealworms larvae, adapting them more effectively to this specific diet. [ABSTRACT FROM AUTHOR]

The drying of electrodes during the manufacturing process strongly affects both the cell performance and production costs of lithium-sulfur (Li-S) batteries. Herein, we present a detailed study on the effect of temperature during the drying process on the performance and binder distribution of sulfurized poly(acrylonitrile) (SPAN) based electrodes using poly(vinylidene fluoride) (PVdF) or poly(acrylic acid) (PAA) as the binder. The electrochemical performance of the PVdF- and PAA-based cathode coatings, which were dried at three different temperatures (30 °C, 60 °C and 90 °C), is analyzed by cycling against lithium metal and utilizing reference-assisted impedance spectroscopy. Time-of-flight secondary ion mass spectrometry (ToF SIMS) is applied on both the surface and the cross-section of the electrodes to determine the binder distribution. Contrary to the PAA-based cathodes, PVdF-based electrodes exhibit binder migration to the electrode surface at elevated coating drying temperatures. The enrichment of PVdF on the surface leads to an increase in the charge transfer resistance and thereby reduces the rate capability. [ABSTRACT FROM AUTHOR]

Copyright of Polimery is the property of Industrial Chemistry Research Institute and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Copyright of Polimery is the property of Industrial Chemistry Research Institute and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

This paper presents investigations of physical properties of hydrogel (HG) based on the lightly crosslinked polymer of acrylic acid "Carbopol ETD 2020" brand under conditions of electrical and thermal modifications when exposed to alternating frequency-modulated signal (AFMS). Data on change in the hydrogel viscosity depending on the gel-forming component concentration, AFMS treatment, and temperature were obtained. It is established that the comparative heating time of modified hydrogels increases with increased concentration of the gel-forming component and under AFMS exposure for thermally modified hydrogels near the water critical point of 4 °C. The advantages of using modernized HG with respect to the traditional fire-extinguishing agent are shown. Thermophysical and rheological properties of HG obtained under electrical modification and hydraulic calculations of watering systems for above-ground vertical stock tanks (VST) of petroleum product proved the justification for their use and showed improving efficiency of installations for thermal protection of tanks storing petroleum products. The compositions of modified HG and their field of application in the nomenclature of tanks for petroleum products were determined. Practical recommendations with calculation results for the use of modified HG on existing fire extinguishing installations in tank batteries are proposed. [ABSTRACT FROM AUTHOR]

The clinical application of triptolide (TPL) in tumor therapy has been greatly limited by its toxicity and inefficient delivery. Herein, a localized and sustained-release thermo-sensitive hydrogel was developed for the intra-tumor administration of TPL. Based on the amphiphilic structure of poly (N -isopropylacrylamide -co- acrylic acid)- g -F68 copolymer, it was able to form nano-micelles to efficiently encapsulate TPL, and then turn into a hydrogel at 37 °C. TPL@nano-gel exhibited a sustained drug release profile in vitro and a stronger anticancer effect caused by "two strikes". The "first strike" was its enhanced cytotoxicity compared to free TPL, due to the enhanced pro-apoptosis effect observed in both MDA-MB-231 and MCF-7 cells caused by the regulation of endogenous mitochondrial pathways. Furthermore, TPL@nano-gel exhibited a "second-strike" through its anti-angiogenesis capabilities mediated through VEGFR-2 signaling inhibition. As expected, after intra-tumoral injection at a 0.45 mg/kg TPL-equivalent dose three times over 14 days in 4T1 tumor-bearing mice, TPL@nano-gel led to lower systemic toxicity and higher antitumor efficacy compared to multiple injections of TPL. In this regard, these findings indicate that this injectable thermo-responsive hydrogel carries great potential for TPL as a safe and effective cancer therapy. Image 1 A themoresponsive nano-hydrogel was fabricated for the sustained release of triptolide (TPL) in the localized treatment of breast tumor. TPL@nano-gel exhibited the enhanced pro-apoptosis effects against breast tumor by the regulation of endogenous mitochondria pathway in vitro and in vivo. [ABSTRACT FROM AUTHOR]

The purpose of present study is to load Metformin HCl into pH-sensitive hydrogels to have sustained release over a period of time. The hydrogel was synthesized from naturally occurring polysaccharide pectin and monomer acrylic acid (AA) using ethylene glycol dimethacrylate (EGDMA) as cross-linker under controlled conditions for polymerization at 45°C for one hr, 50°C for two hrs, 55°C for three hrs, 60°C for four hrs and finally 65°C for 12 hrs. Hydrogels were characterized for dynamic/equilibrium swelling, sol-gel fraction analysis, diffusion coefficient and percentage porosity. Hydrogels were tested by FTIR, XRD and SEM for structure and surface morphology respectively. Experimental in-vitro drug release data was applied to kinetic models. Formation of strong bonding between pectin and AA was supported by FTIR. The intensity of XRD peaks was reduced in non-loaded and loaded hydrogels compared to active drug substance. The non-loaded hydrogel showed discrete porous structure whereas loaded hydrogels were fibrous and smooth. Hydrogels showed higher swelling in the solutions of pH 6.5 and 7.5 as compared to in the solutions of pH 1.2 and 5.5. The diffusion coefficient decreases with the increase of AA and pectin concentrations. It was observed upon increasing the EGDMA concentration porosity decreases. The release of drug from all compositions of hydrogels took place through non-Fickian diffusion mechanism. [ABSTRACT FROM AUTHOR]

Within the context of environmental impact, the scope of the current study is focused on researching effect of low temperature plasma treatment on dyeing of polyester fabrics. This is done in terms of low temperature, short time and improved fastness. Plain weave 100% polyester fabrics were subject to low frequency plasma treatment under a well selected power and duration using acrylic acid (AA) monomer. Plasma polymerization treatment was investigated by considering water absorption, ESCA and SEM analysis outputs, followed by dyeing and related color measurements. Consequently, results were compared with dyed untreated fabrics. Additionally, washing and rubbing fastness were also examined to exploit the effects of plasma on permanentness of short time (<30 minutes) and low temperature (<110°Q dyeing compared to coventional disperse dyeing. This work's appearant result was the effectiveness of acrylic acid plasma polymerization technique on dye uptake of polyester fibers in disperse dyeing. However, high impact result of the work was short time (30min) disperse dyeing of polyester fabrics. We can conclude that the mentioned method can be an alternative to conventional long time dyeing (60min) with acrylic acid plasma polymerzation treatment, increasing dry rubbing fastness. This results are promising for an ecological and energy saving alternative to conventional disperse dyeing. [ABSTRACT FROM AUTHOR]

• We investigated the textile fiber composition of women's clothing in the retail trade of Santos (Brazil), and we verify that the inspected garments consisted mainly of polyester, viscose, and cotton fibers. • We calculate clothes' ecological footprints by multiplying the fibers' proportions by their sustainability notes and adapt the results to the current Brazilian labeling system. • Ecological footprint to clothing labels can influence consumer purchasing decisions and encourage the development of more sustainable products. Then, we propose the application of the labeling system as an environmental management tool for the Brazilian fashion sector. The textile industry presents one of the most threatening patterns of production concerning the global environmental impact. In this article, we investigated the textile fiber composition of women's clothing in the retail trade of Santos (Brazil), through information read on the labels during July 2017 (winter) and January 2018 (summer), in three types of stores: department, popular and thrift stores. The inspected garments consisted mainly of polyester, viscose, and cotton fibers, although fibers such as elastane, polyamide, and acrylic were eventually present as fabric complements. We calculate clothes´ ecological footprints by multiplying the fibers´ proportions by their sustainability notes and adapt the results to the current Brazilian labeling system. We did not detect ecological footprints differences in types of stores, nor seasons of the year. There was predominance (69 %) of clothes with a high ecological footprint (low sustainability). Exposure of the ecological footprint to clothing labels can influence consumer purchasing decisions and encourage the development of more sustainable products. Thus, we propose the application of the labeling system as an environmental management tool for the Brazilian fashion sector. [ABSTRACT FROM AUTHOR]

To predict the novel poly(benzimidazole):poly(acrylic acid) (PBI:PAA) blend membranes proton conductivity, an ionic conductivity equation combined with thermodynamic model is proposed where different proton transport mechanisms including Grotthuss, vehicle and surface hopping mechanisms are considered in calculations. Based on the PAA titration behavior, by increasing the number-average molecular weight (M n), apparent acidity of PAA decreases. Hence, to calculate the concentration of protons involved in different mechanisms, a new modification in the predictive model is suggested by considering acidity and its relation with M n. Effect of temperature, PAA molar ratio and M n on the membranes proton conductivity is investigated theoretically and compared with experimental data. The conductivity of membranes is increased by increasing the M n and molar ratio of PAA where the highest proton conductivity is attributed to the membrane with PAA of M n = 105 g · mol-1 and molar ratio of PBI:PAA = 1:4. The experimental proton conductivity and predicted results show a good agreement in comparison to the previous models based on Nernst-Einstein equation, indicating that acidic behavior, which is usually omitted in theoretical models, has an important effect on the total proton conductivity of PBI:Polyacid membranes, especially at higher temperatures. [ABSTRACT FROM AUTHOR]

With rapidly rising demand of power in the field of flexible and wearable electronics, electrolytes being one of the influential components of the electrochemical energy storage devices and are getting more attention as their physical and chemical properties play vital role in device performance. Hydrogel electrolytes are emerging as novel materials for use in supercapacitors due to their diverse 3D porous network, bendable structure and tuneable properties. In the present work, Poly (acrylic acid) hydrogel has been synthesized using free-radical polymerization in the presence of chemical crosslinker N,N'-methylene bisacrylamide (MBA). The prepared hydrogels were soaked in four different molar concentration of lithium perchlorate (LiClO4) for 48 h to form double network hydrogel electrolytes. The structural and morphological characteristics of hydrogel electrolytes have been investigated using Fourier transform infrared-attenuated total reflectance (FTIR-ATR), X-ray diffraction and field emission scanning electron microscope (FESEM). In addition, the mechanical strength of hydrogel electrolytes was observed. The electrochemical studies including cyclic voltammetry (CV) and galvanic charge-discharge (GCD) investigated the performance of fabricated cells (AC/AA1/AC, AC/AA2/AC, AC/AA3/AC, and AC/AA4/AC) using hydrogel electrolytes in terms of specific capacitance, energy density and power density. Electrochemical studies show that AC/AA3/AC (activated carbon/acrylic acid (1.5 M LiClO4)/activated carbon) is the optimised electrochemical cell among the fabricated cells of hydrogel electrolytes. AC/AA3/AC achieved maximum specific capacitance of 115 F gâ?'1 at 3 mV sâ?'1 and 132.20 F gâ?'1 at 50 mA gâ?'1 with energy density and power density of 18.36 Wh kgâ?'1 and 1000 W kgâ?'1, respectively. All the results indicated significantly that poly (acrylic acid)/LiClO4 hydrogel electrolytes are competitive candidates for application in supercapacitors [ABSTRACT FROM AUTHOR]

Poly(acrylic acid) (PAA) is added as a binder to the water-based slurry of Ni-rich Li(Ni0.8Co0.1Mn0.1)O2 (NCM811) powder. After adding PAA, the pH of the slurry changes from strongly alkaline to nearly neutral (pH9.0), making it suitable for casting on the aluminum current collector without corroding the aluminum (Al) and a largely increased adhesion from 318 to 458 kg m-2 after drying. The use of PAA also improves the dispersion of the slurry, because the carboxyl groups of PAA can interact with NCM811 to help stabilize the electrode particles in the slurry. Given the improved dispersion, reduced corrosion potential, and better adhesion, the resultant NCM811 cathode exhibits good structural integrity and greatly lowered charge-transfer resistance from 37.0 to 8.5 O, showing a high initial capacity of 189.2 mAh g-1 and capacity retention of 84.2% after 100 charge-discharge cycles under 0.2C. [ABSTRACT FROM AUTHOR]