Carboxylate Form Research Articles

Technological quality improvement of gluten-free dough and chapatti-making by incorporation of modified oat 1,4-β-D-glucan

The present study aimed to explore the contribution of untreated (UtβG) and modified oat 1,4-β-D-glucan (OzβG) to the quality of gluten-free chapattis at varying concentrations (0, 1.5, 3, and 4.5 % labelled as M0, M1, M2 and M3 for maize chapattis and F0, F1, F2 and F3 for finger millet chapattis, respectively). The functionality of flours was significantly enhanced by the addition of UtβG and OzβG. However, OzβG incorporated flour exhibited a more pronounced influence on both functional and farinographic parameters when compared to flours with UtβG. Further, the hardness of the chapattis decreased with incorporation of OzβG and it was lowest for M2 and F2 i.e. 6.38 N and 5.27 N, respectively due to the formation of more carboxyl and hydroxyl groups, which had more affinity towards water molecules. The sensory analysis indicated that OzβG incorporated M2 and F2chapattis exhibited the highest overall acceptability. Hence, this study provides valuable insights into the utilization of UtβG and OzβG for the formulation of gluten-free chapattis with better dough characteristics and chapatti-making properties.

Epoxidized cardanol oleate (ECD-OA) as an effective biobased chain extender of polylactic acid (PLA)

Moisture exposure during polyester processing can lead to degradation, resulting in the formation of carboxyl and hydroxyl end-groups. To preserve mechanical properties, thorough drying and the use of chain extenders like epoxy acrylates and isocyanates during extrusion are crucial for maintaining or enhancing molecular weight through in-situ reactions. Our study introduced epoxidized cardanol oleate (ECD-OA), containing epoxy and long-chain alkyl groups, as a potential chain extender, and compared its effectiveness with commercially available epoxidized cardanol glycidyl ether (cardolite NC514). Compared to neat PLA without chain extension, the addition of 1 phr ECD-OA resulted in an increase in the molecular weight (Mw) of PLA from 15.3 × 104 g/mol to 17.1 × 104 g/mol, demonstrating a chain extension efficiency of 11.8 %. The melt flow rate of PLA decreased from 9.9 g/10 min to 5.0 g/10 min, and the initial thermal degradation temperature of PLA increased by 5.7 °C. Upon chain extension, there was a substantial increase in both the elongation at break and tear resistance of the PLA film. The results demonstrate that ECD-OA can extend PLA molecular chains through chemical reactions and promote entanglement with the long alkane chain, consequently enhancing the mechanical and thermal properties of PLA. Due to the enzyme's preference for biobased small molecules, the PLA film with the addition of a biobased chain extender is more prone to enzymatic degradation compared to neat PLA. To conclude, ECD-OA acts as a bio-based chain extender that improves the performance of PLA while also enhancing its biodegradability.

Identification of clerodane diterpene modifying cytochrome P450 (CYP728D26) in Salvia divinorum - en route to psychotropic salvinorin A biosynthesis.

Salvia divinorum is a hallucinogenic plant native to the Oaxaca in Mexico. The active ingredient for psychotropic effects in this plant is salvinorin A, a potent and highly selective κ-opioid receptor agonist. Salvinorin A is distinct from other well-known opioids, such as morphine and codeine, in that it is a non-nitrogenous diterpenoid with no affinity for μ-opioid receptor, the prime receptor of alkaloidal opioids. A terpene opioid that selectively targets a new opioid receptor (κ-opioid receptor) can be instrumental in developing alternative analgesics. Elucidation of the salvinorin A biosynthetic pathway can help bio-manufacture diverse semi-synthetic derivatives of salvinorin A but, to date, only two enzymes in the Salvinorin A pathway have been identified. Here, we identify CYP728D26 that catalyzes a C18 oxygenation on crotonolide G, which bears a clerodane backbone. Biochemical identity of CYP728D26 was validated by in vivo reconstitution in yeast, 1H- and 13C-NMR analyses of the purified product, and kinetic analysis of CYP728D26 with a Km value of 13.9 μM. Beyond the single oxygenation on C18, collision-induced dissociation analysis suggested two additional oxygenations are catalyzed by CYP728D26 to form crotonoldie G acid, although this carboxylic acid form is a minor product. Its close homologue CYP728D25 exhibited a C1-hydroxylation on the clerodane backbone in a reconstituted yeast system. However, CYP728D25 showed no activity in in vitro assays. This result implies that catalytic activities observed from overexpression systems should be interpreted cautiously. This work identified a new CYP catalyst and advanced our knowledge of salvinorin A biosynthesis.

Vanadium-Containing Ionic Liquids Derived from Complexes of Modified Edta as Catalysts of Epoxy-Anhydride Ring-Opening Copolymerization.

A new type of vanadium-containing ionic liquids (ILs) was synthesized by cation exchange from barium salts of oxidovanadium(IV) complexes stabilized by edta and its congeners (dcta, oedta, and heedta) serving as pentadentate ligands. All starting barium salts and several magnesium and cesium salts, serving as models for the cation exchange, were structurally characterized by single-crystal XRD analysis. The synthesized ILs consisting of organic cations (Bu4N+, Bmim+, and Bu4P+) and complex anions ([VO(edta)]2-, [VO(dcta)]2-, [VO(oedta)]-, and [VO(heedta)]-) were characterized by analytical and spectroscopic methods including EPR spectroscopy and cyclic voltammetry. Then, ILs were tested as catalysts for the ring-opening copolymerization of epoxy resin with cyclic anhydride showing significant catalytic activity, which led to production of highly cross-linked glassy thermosets. A detailed isothermal DSC kinetic study was performed for the most promising IL showing that the progress of cross-linking can be successfully fitted by the Kamal-Sourour model. Based on the DSC and NIR results, the initiation mechanism of the cross-linking in the presence of vanadium-containing IL was suggested. IL had ability to activate a rapid hydrolysis of anhydride cycle and the formed carboxyl groups initiated a polyesterification. In parallel, the role of imidazolium cation of IL for the initiation of chain-growth anionic copolymerization is also discussed.

Analysis of the effects of Pr1-xCexCoO3/dolomite catalyst on energy saving and carbon reduction in biomass gasification for the production of hydrogen-rich syngas

Biomass is considered a renewable green coal, and its clean and efficient utilization is of great significance for energy conservation and carbon reduction. One of the most critical aspects of biomass gasification is the selection of an appropriate catalyst. In this study, we synthesized a catalyst with 10 % Pr1-xCexCoO3 supported on dolomite using the sol-gel method. We conducted graded internal circulation gasification experiments to produce hydrogen-rich syngas. The effects of element substitution in PrCoO3, temperature, catalyst composition, and steam injection rate on the products were investigated. The optimal gasification conditions were determined through response surface regression analysis. The data indicate that this catalyst can improve gasification efficiency, with Pr0.4Ce0.6CoO3/Dol showing the best catalytic performance. It effectively reduces the required gasification temperature and steam amount, decreases CO2 production, and increases CO and H2 yields. The catalyst accelerates the cleavage and ring-opening reactions of hydrocarbons, leading to terminal chain hydroxylation, followed by the dehydration-condensation of methyl groups into ethers. As the temperature rises, the rate of carboxyl group removal gradually exceeds the rate of carboxyl group formation via the oxidation of hydroxyl and ether chains, resulting in an initial increase and then a decrease in the number of carboxyl groups. Under optimal gasification conditions, CO2 production is reduced by one-fourth compared to using a dolomite catalyst.

Characterization of Composite Materials Using Carbon Nano Tube Carboxy Group Introduction and Aluminum Oxide Synthesis

The high integration and high density of semiconductor packages are generating increased heat in electronic devices, leading to issues such as reduced lifespan and malfunctions in electronic devices. In response, research on thermal interface materials is being conducted to address heat generated from heat sources, and various studies, particularly those applying carbon nano tube, are notable in this regard. However, in the case of carbon nano tube, there are challenges in industrial application due to the occurrence of cohesive forces through van der Waals interactions. Therefore, in this study, the characteristics were analyzed through the formation of carbon nano tube carboxyl groups (–COOH) and the synthesis of aluminum oxide via chloride (–COCl) formation. After the chloride process, a functional group –COCl was confirmed at 430 cm−1. It was confirmed that the electrical properties were improved as a result of the CNT, CNT carboxyl, and chloride process. It is believed that the electrical properties improved as impurities were removed during the acid treatment process. In addition, it is believed that the electrical properties were improved due to the increase in intermolecular forces between CNTs. Through this, it is determined that the application of carbon nano tube and aluminum oxide composite materials can be highly beneficial for thermal conductivity heat dissipation filler applications.

Effects of Na-salt solutions on the biomass pyrolysis and CO2-assisted gasification behavior

This study aims to explore the effects of different Na-salt solutions on the behavior of biomass pyrolysis and gasification. The same molar number of Na was introduced via the impregnation method. The distinction was that pine wood impregnated with neutral NaCl and Na2SO4 solutions was the Na in physical adsorption form, whereas the alkaline Na2CO3, CH3COONa, and NaOH solutions resulted in both carboxylate form and physical adsorption form. Thermogravimetric analysis results showed that impregnating alkaline Na solution was more potent than the neutral Na solution in reducing the thermal stability of pine wood structures. Results of pyrolysis and CO2-assisted gasification indicated that samples impregnated with the alkaline Na solutions obtained lower CO and higher CO2 evolution than that from the neutral Na solution during pyrolysis. The Na in carboxylate form was more difficult to volatilize, and formed more Na-containing active catalytic structures, resulting in biochar that provided higher reactivity in gasification. However, different Na solutions on the biochar's gasification reactivity showed the order of NaCl-loaded sample < CH3COONa-loaded sample ∼ NaOH-loaded sample < Na2SO4-loaded sample < Na2CO3-loaded sample. This can be attributed to the combined effects of Na-containing active catalytic structures, along with the active surface salt complex formed by molten Na species and biochar. As for the overall energy efficiency of pine wood impregnated with different Na solutions, gasification of Na2CO3-loaded sample provided the highest maximum overall energy efficiency (49.2 %). The results presented here provide useful insights for practical application of using syngas for electricity generation.

Development of Graphene Oxide-Based Anticancer Drug Combination Functionalized with Folic Acid as Nanocarrier for Targeted Delivery of Methotrexate.

Graphene has become a prominent material in cancer research in recent years. Graphene and its derivatives also attract attention as carriers in drug delivery systems. In this study, we designed a graphene oxide (GO)-based methotrexate (MTX)-loaded and folic acid (FA)-linked drug delivery system. MTX and FA were bound to GO synthesized from graphite. MTX/FA/GO drug delivery system and system components were characterized using Fourier transform infrared spectroscopy (FTIR), differential calorimetric analysis (DSC), scanning electron microscopy (SEM), transmission electron microscopy (TEM), zeta potential analysis, and dimension measurement (DLS) studies. SEM and TEM images confirmed the nanosheet structure of GO synthesized from graphite, and it was shown that MTX/FA binding to GO transformed the two-dimensional GO into a three-dimensional structure. FTIR and DSC graphs confirmed that oxygen atoms were bound to GO with the formation of carboxylic, hydroxyl, epoxide, and carbonyl groups as a result of the oxidation of graphite, and GO was successfully synthesized. Additionally, these analyses showed that MTX and FA bind physicochemically to the structure of GO. The in vitro Franz diffusion test was performed as a release kinetic test. The release kinetics mathematical model and correlation coefficient (R2) of MTX-loaded GO/FA nanomaterials were found to be the Higuchi model and 0.9785, respectively. Stiffness analyses showed that adding FA to this release system facilitated the entry of the drug into the cell by directing the system to target cells. As a result of the stiffness analyses, the stiffness values of the control cell group, free MTX, and MTX/FA/GO applied cells were measured as 2.34 kPa, 1.87 kPa, and 1.56 kPa, respectively. According to these results, it was seen that MTX/FA/GO weakened the cancer cells. Combined use of the MTX/FA/GO drug delivery system had a higher cytotoxic effect than free MTX on the MDA-MB-231 breast cancer cell line. The results showed that the synthesized MTX/FA/GO material has promising potential in cancer cell-specific targeted therapy for MTX as a drug delivery system.

Broken crystal symmetry of MWCNTs as the key factor in improvement of carboxyl functionalization

Carbon nanotubes functionalized with carboxyl groups (COOH-CNTs) find their application in energy storage, sensing, improving mechanical stability and biomedicine. So a facilitation of COOH-groups bonding to CNTs is one the modern scientific challenges. In this study untreated multi-walled CNT (MWCNTs), nitrogen-doped MWCNT (N-MWCNTs) and ion-beam irradiated N-MWCNTs (irr-N-MWCNTs) were synthesized using the CVD method. Characterizations were performed via HRTEM, Raman, XPS, and NEXAFS spectroscopy. Irr-N-MWCNTs demonstrated the largest amount of carbon crystallites, the presence of Stone-Wales defects as well as the regions of tensile-compressive, shear and torsional deformation. All these factors contributed to increase of carboxyl functionalization at the tube’s surface. On the base of experimental data, the atomic supercells of N-MWCNTs and irr-N-MWCNTs were built by the self-consistent-charge density-functional tight-binding method (SCC DFTB). Through SCC DFTB, we quantified atomic rearrangements, electronic structures, charge transfers, total energies, and the forces and energy barriers relevant to COOH bonding. The twisting of irr-N-MWCNTs supercells by 45 degrees decreased the barrier to the carboxyl formation in 2.5 times in comparison to undeformed nanotubes. Our findings reveal that nitrogen addition, ion-beam irradiation, and induced deformations create the necessary conditions for COOH functionalization by altering the physicochemical surface properties of MWCNTs.

Biochar derived from animal and plant facilitates synergistic transformation of heavy metals and phosphorus in sewage sludge composting

This study investigated the influence of plant-derived biochar (PB) and animal-derived biochar (AB) on behavior of heavy metals and phosphorus fractions during sewage sludge composting. PB was highly effective in reducing the bioavailability of Zn and Cu by 39% and 50%, respectively, while AB decreased the bioavailability of Pb (30%) and Cd (12%). Both biochar increased available phosphorus by over 38%. Acid extractable and bioavailable Pb in AB, and water-soluble, oxidizable and total Zn, acid extractable and oxidizable Cu in PB were positively correlated with moderately resistant organic phosphorus (MROP). Besides, in AB, Cd had strong and positive correlation with highly resistant organic phosphorus (HROP). This suggested biochar facilitated the formation of stable organometallic complexes through binding metal ions to phosphorus fractions, with notable differences based on biochar source. FT-IR showed biochar promoted humification, with PB enhancing carboxyl and polysaccharide formation, while AB encouraged quinone and aryl ether structures. These surface functional groups on the biochar likely contributed to heavy metals and phosphorus binding through chelation, adsorption, and electron shuttling.

Effect of Fenton reaction parameters on the structure and properties of oxidized wheat starch

Wheat starch was oxidized through a Fenton reaction by hydrogen peroxide and Iron II sulfate as a catalyst at various concentrations and reaction duration. The formation of carbonyl and carboxyl groups confirmed the starch oxidation as determined with Fourier-transform infrared (FTIR) spectroscopy. The degree of oxidation was estimated by carbonyl and carboxyl titration. The various oxidized wheat starches presented considerable variations in their oxidation level as a function of the catalyst concentration and oxidative process duration. The effect of the Fenton reaction parameters on the starch macromolecular chains and microstructure was evaluated by X-ray diffraction and amylose content estimation. Significant depolymerization of the starch macromolecules was observed, mainly in the starch amorphous phase, followed by a degradation of the crystalline phase at a higher oxidation level. SEM observations revealed changes in starch structure, which ranged from minor degradation of the starch granules to a more crosslinked morphology.

Fossil steroid acids can arise from microbial alteration of steranes

Steroid acids are unique molecular fossils composed of a steroid carbon skeleton linked to a carboxyl group. These biomarkers contain special geological and biological clues in their structures. However, the origin of steroid acids remains a subject of debate, and there is a lack of direct evidence in previous studies. Here, we present experimental evidence for the origin of steroid acids. The origin of steroid acids during biodegradation in crude oil was observed for the first time. Molecular structures of these steroid acids reveal that they arose from steranes via bacterial oxidation of sidechain terminal methyl groups. Our results suggest that microbial activities indeed contribute to the formation of carboxyl groups on the eukaryotic steroid skeletons, and we believe steroid acids are a promising biomarker for both geomicrobial processes and ancient eukaryotic life in the rock record.

A sensitive bioanalytical ultra-high-performance liquid chromatography-tandem mass spectrometry method for the simultaneous quantitation of lactone and carboxylate forms of topotecan in plasma and vitreous.

Topotecan (TPT) is used in the treatment of retinoblastoma, the most common malignant intraocular tumor in children. TPT undergoes pH-dependent hydrolysis of the lactone ring to the ring-opened carboxylate form, with the lactone form showing antitumor activity. A selective, and highly sensitive ultra-high-performance liquid chromatography-tandem mass spectrometry method was developed for the determination of both forms of TPT in one mobile phase composition in plasma and vitreous humor matrices. The method showed an excellent linear range of 0.375-120ng/mL for the lactone. For the carboxylate, the linear range was from 0.75 to 120ng/mL. The matrix effect and the recovery for the lactone ranged from 98.5% to 106.0% in both matrices, for the carboxylate form, it ranged from 94.9% to 101.2%. The dynamics of the transition between TPT lactone and TPT carboxylate were evaluated at different pH environments. The stability of TPT forms was assessed in plasma and vitreous humor at 8 and 37°C and a very fast conversion of lactone to carboxylate form occurred at 37°C in both matrices. The method developed facilitates the investigation of TPT pharmacodynamics and the release kinetics in the development of the innovative local drug delivery systems.

Effect of Single and Dual Modifications on the Physicochemical Properties of Sago Starch Modified by Ozonation and Acetylation

Abstract Dual-step starch modification is an effort to eliminate weaknesses in single-step modification. This research aims to study the effect of single-step or dual-step modification methods on the physicochemical properties of sago starch. The single step consists of ozonation (Oz) and acetylation (As), while the dual step (sequentially), namely ozonation-acetylation (Oz-As) and acetylation-ozonation (As-Oz). The physiochemical responses measured were water content, carbonyl content, carboxyl content, acetyl content, water solubility index (WSI), water absorption index (WAI), and color. Ozonation causes the formation of carbonyl and carboxyl groups, and the modification process certainly causes the addition of carbonyl and carboxyl groups both in single step and dual-step. Acetylation causes higher acetyl group values in either single-step (As) or dual step (Oz-As and As-Oz) compared to original sago starch. There was a significant difference between the single and dual steps in the WSI and WAI values. The characteristics of Ozonated-acetylated (Oz-As) modified sago showed starch the highest WSI and WAI results. The water content in single-step modified sago starch compared to native sago starch has no significant difference in water content, whereas the dual-step modified sago starch has a higher water content than the native one.

Cytotoxic glutarimide-containing polyketides isolated from Streptomyces sp. JCM 4793.

Glutarimide-containing polyketides usually exhibit anti-fungi activity, which was well exampled by cycloheximide. In our work, three new polyketide structures, 12-amidestreptimidone (1), 12-carboxylstreptimidone (2) and 3-(5S,8R)-(2-amino-2-oxoethyl-2'-methoxy-2'-oxoethyl)-8,10-dimethyl-7-oxododeca-5-hydroxy-9E,11-diolefin (3) were isolated from Streptomyces sp. JCM 4793. 3 without the glutarimide moiety is not active against fungi as expected, while 1 bearing the amide moiety is much more active than its carboxylic form 2. Here we report the isolation, structural elucidation, antifungal activity, and proposed biosynthesis pathway of 1-3.

Flexible laser-induced graphene electrodes on polyimide film: Hybrid nanoflower-modified dielectric microjunctions for non-faradaic analysis

Laser-induced Graphene (LIG) electrodes on flexible substrates have attracted significant research interest, making them an excellent alternative to conventional fabrication of transducers on rigid planar substrates. In this study, four individual capacitor-like triangular LIG electrodes were fabricated on polyimide (PI) film with micron gap (MG) spacing of 30, 66, 125 and 180 µm, to study the relationship between gap spacing and capacitance. A novel N, N-carbonyldiimidazole-copper (CDI-Cu) hybrid nanoflower (NF) was synthesised via one-pot biomineralization and deposited at the triangular junction of acid-base treated LIG-MG for the immobilization of neutravidin. The gap spacing and structure of the LIG-MG were analysed using high-resolution microscopes, revealing a porous nanofiber-like graphene structure. X-ray Photoelectron Spectroscopy (XPS) of acid-base treated PI film proved carboxyl group formation. A decrease in capacitance was observed with an increasing gap spacing in a non-faradaic environment. The capacitance of CDI-Cu NF following neutravidin modification for 30, 66, 125 and 180 µm spacings were 1.77E-07, 1.36E-07, 4.73E-08, 4.84E-08 F, respectively, suggesting excellent biomolecular modification sensitivity of the LIG-MG with 30 µm spacing. A comparative analysis of dielectric performance for different gap-spaced devices revealed that a 30 µm spacing would be optimal for bio-capturing because of the close confinement of biomolecules for smaller gapped areas.

Accelerating effect of metal ionic liquids for epoxy-anhydride copolymerization

One of the main drawbacks of high-performance epoxy-anhydride thermosets is slow cross-link kinetics requiring high temperature and long curing cycle. Herein, the accelerating effect of imidazolium metal-based ionic liquids (MILs) bearing (FeCl4)-, (ZnCl4)2-, and (CoCl4)2- anions on epoxy-anhydride copolymerization was investigated. It was observed that MILs accelerated bisphenol diglycidyl ether (DGEBA) − methylhexahydrophthalic anhydride (MHHPA) cross-linking, better than the reference catalysts (1-methylimidazole and 1-butyl-3-methylimidazolium chloride), especially at low temperatures through their ability to activate a rapid anhydride ring opening and formation of carboxyl groups, which initiates polyesterification. A detailed investigation of the polymerization mechanism revealed the formation of alternating epoxy-anhydride copolymers although several MILs-induced initiation mechanisms were detected. Despite the multiple-initiation consisting of imidazole, counter anion, and polyesterification pathways, the cross-linking kinetics was successfully fitted up to vitrification by the Kamal-Sourour model. Finally, MILs-induced cross-linking leads to homogeneous network build-up enabling to produce thermosetting materials with an increased cross-link density, a glass transition temperature above 150 °C, and excellent thermal stability.

Technological quality improvement of gluten‐free eggless cakes by the incorporation of untreated and modified hydrocolloids

SummaryThe study examined the impact of untreated β‐glucan (UtβG) and ozonated β‐glucan (OzβG) on the characteristics of batter and gluten‐free eggless cake prepared using finger millet and flaxseed flour by encompassing a comprehensive analysis of physical, rheological, textural, morphological, sensory and nutritional properties. As the β‐glucan level increased, batter density and viscosity demonstrated an upward trend. The frequency sweep test revealed that β‐glucan altered the rheological parameters of batter, with the storage modulus (G′) surpassing the loss modulus (G″), indicating more elastic properties. The inclusion of OzβG resulted in improved physical characteristics and decreased the cake hardness, attributed to the formation of carboxyl and hydroxyl groups. Cakes incorporated with 1.5% OzβG had the highest overall acceptability score. Hence, this study sheds light on the utilisation of untreated and modified oat β‐glucan in the development of gluten‐free eggless cake, potentially aiding the bakery industry in meeting the rising demands for such products.

Development of an ELISA with acidification treatment for an antibody conjugate incorporating Exatecans

The successful development of Sacituzumab Govitecan and Trastuzumab Deruxtecan has made camptothecin derivatives one of the most popular payloads for antibody-drug conjugates (ADCs). Camptothecin and its derivatives all exist in a pH-dependent equilibrium between the carboxylate and lactone forms. Such transformation may lead to differences in the ratio of the two molecular forms in calibration standards and biological matrix (bio-matrix) samples, thereby leading to inaccurate conjugated antibody results. In this study, we reported an enzyme-linked immunosorbent assay (ELISA) free of the aforementioned influence for the detection of the Exatecans-conjugated antibody (conjugated SM001) in cynomolgus monkey serum. The assay was developed by first acidifying all samples with glacial acetic acid (HAc), then performing neutralization and thereafter capturing conjugated SM001 with anti-Exatecan monoclonal antibody (mAb) and detecting it with biotinylated Nectin4 (hNectin4-Bio) and horseradish peroxidase-labeled streptavidin (SA-HRP). Results showed that all tested performance parameters met the acceptance criteria. The conjugated SM001 concentrations obtained were in parallel to but slightly lower than total antibody (TAb) throughout the pharmacokinetic (PK) study, revealing that the assay strategy implemented for conjugated SM001 measurement worked well for the elimination of interference triggered by the heterogeneous existence of the lactone and carboxylate forms of Exatecan (lactone-Exatecan and carboxylate-Exatecan).

Surface modification of poly (ethylene terephthalate) using imidazolium-based ionic liquids

Ionic liquids (ILs), with their unique characteristics, are widely known as new alternatives for solvents and catalysts used in various chemical reactions. Due to their extensive range of applications and environmental compatibility, they are suitable options for treating fibrous substrates. In this regard, this paper focuses on investigating the possibility of poly (ethylene terephthalate) surface modification via imidazolium-based ILs. Surface modification was carried out under different process conditions by varying the temperature and the catalyst. The possibility of treating samples in the IL solution for the second time was also examined. Moreover, the effect of the modification on the dyeing of polyester with disperse dye without carrier at 100 °C was studied. The samples’ wettability properties were investigated through several test methods by measuring vertical wicking height, wetting time, drop contact angle, surface resistivity and absorption of methylene blue dye. The chemical and physical changes of the modified samples were also evaluated via scanning electron microscopy images, Fourier-transform infrared spectroscopy (FTIR) spectra and mechanical tests. Results demonstrate that treatment with [BMIM]Cl and [BMIM]Br induces morphological changes on the fibre surface, creating grooves and voids. FTIR analysis and Methylene blue staining test confirm the formation of hydroxyl and carboxyl groups, enhancing the fabric's hydrophilicity and dyeability. Wettability tests reveal that increased water absorption leads to reduced electrical resistivity. Mechanical tests indicate a slight reduction in tensile strength attributed to surface roughness.