Carboxymethyl Cellulose Polymer Research Articles

Gastrointestinal-inert prebiotic micro-composites improve the growth and community diversity of mucosal-associated bacteria.

The process of microencapsulation and the development of microparticle-based drug formulations have gained increased pharmaceutical interest, particularly for drug delivery and bacterial-encapsulation purposes for probiotic delivery. Existing studies have examined microcomposite (MC) responses to gastrointestinal (GI) conditions with the aim of controlling disintegration, and thus release, across the small and large bowel. However, the delivery of MCs which remain intact, without degrading, could act as bacterial growth scaffolds or materials providing a prebiotic support, conferring potentially beneficial GI health properties. This present study employs prilling as a method to produce a portfolio of MCs using a variety of biopolymers (alginate, chitosan, pectin and gellan gum) with a range of MC diameters and density compositions. Fluorescent probes are co-encapsulated within each MC to enable flow-cytometry directed release profile assessments following exposure to chemical simulated gastric and intestinal digestion conditions. We observe that MC size, gel-strength, density, and biopolymer material all influence response to gastric and intestinal conditions. Gellan gum (GG) MCs demonstrated complete resistance to disintegration throughout GI-simulation in the stomach and small intestine. Considering these MCs could reach the colon intact, we then examined how such MCs, doped with prebiotic growth supporting Carboxymethyl cellulose (CMC) polymers, could impact microbial communities using a bioreactor model of the colonic microbiome. Following supplementation with GGCMC MCs, mucosal bacterial diversity (using 16 s rRNA sequencing and Shannon entropy and observed feature diversity metrics) and taxonomic composition changes were observed. Concentrations of short chain fatty acid (SCFA) metabolites were also found to be altered. This is the first study to comprehensibly examine how MC physicochemistry can be manipulated to tailor MCs to have the desired GI release performance and subsequently, how GI-resistant MCs could have influential microbial altering properties and could be adopted in novel prebiotic strategies.

Gelatin-carboxymethyl cellulose/iron-based metal-organic framework nanocomposite hydrogel as a promising biodegradable fertilizer release system: Synthesis, characterization, and fertilizer release studies

Application of fertilizers is a routine method in agriculture to increase the fertility of plants However, conventional fertilizers have raised serious health and environmental problems in recent years. Therefore, the development of biodegradable superabsorbent hydrogels based on natural polymers with the capability for fertilizer controlled release has attracted much interest. In the current research, a novel nanocomposite hydrogel based on gelatin and carboxymethyl cellulose polymers enriched with an iron based metal- organic framework (MIL-53 (Iron)) was prepared. The prepared nanocomposite hydrogel was loaded with NPK fertilizer to obtain a slow release fertilizer system. The structural properties of the nanocomposite hydrogel were investigated using FTIR, XRD, and SEM techniques. The swelling and fertilizer release behavior of the nanocomposite hydrogel were evaluated in conditions. Results showed that by adding iron-based metal organic framework to the hydrogel matrix, the water absorption capacity of the hydrogel system was increased to 345.8 (g/g). Fertilizer release studies revealed that the release of fertilizer from the nanocomposite matrix has a slow and continuous release pattern. Therefore, the synthesized nanocomposite has an appropriate strength and high potential to be used as a slow-release fertilizer system.

Surface Immobilization of Oxidized Carboxymethyl Cellulose on Polyurethane for Sustained Drug Delivery.

Polyurethane (PU) has a diverse array of customized physical, chemical, mechanical, and structural characteristics, rendering it a superb option for biomedical applications. The current study involves modifying the polyurethane surface by the process of aminolysis (aminolyzed polyurethane; PU-A), followed by covalently immobilizing Carboxymethyl cellulose (CMC)polymer utilizing Schiff base chemistry. Oxidation of CMC periodically leads to the creation of dialdehyde groups along the CMC chain. When the aldehyde groups on the OCMC contact the amine group on a modified PU surface, they form an imine bond. Scanning electron microscopy (SEM), contact angle, and X-ray photoelectron spectroscopy (XPS) techniques are employed to analyze and confirm the immobilization of OCMC on aminolyzed PU film (PU-O). The OCMC gel incorporates Nitrofurantoin (NF) and immobilizes it on the PU surface (PU-ON), creating an antibacterial PU surface. The confirmation of medication incorporation is achieved using EDX analysis. The varying doses of NF have demonstrated concentration-dependent bacteriostatic and bactericidal effects on both Gram-positive and Gram-negative bacteria, in addition to sustained release. The proposed polyurethane (PU-ON) surface exhibited excellent infection resistance in in vivo testing. The material exhibited biocompatibility and is well-suited for biomedical applications.

Fe-Gallic acid metal organic framework-encapsulated cellulose polymer thin film for fluorescent immunoassay of prostate-specific antigen

A novel, highly sensitive, and cost-effective biosensor for prostate-specific antigen (PSA) detection has been developed using bioengineered nanotechnology. This biosensor integrates a Fe(III)-Gallic acid metal organic framework (Fe-GA MOF) embedded in a carboxymethyl cellulose polymer thin film, coupled with a PSA monoclonal antibody for capture. The resulting sensor demonstrates exceptional performance in detecting PSA levels within a wide concentration range (0.1–170 ng/mL), with a remarkable limit of detection of 0.06 ng/mL. This advanced technology surpasses conventional methods by providing enhanced sensitivity, stability, and reduced interference. The biosensor holds immense potential for early prostate cancer diagnosis, monitoring treatment response, and detecting recurrence. Moreover, its applicability may extend to other cancers characterized by elevated PSA levels, ultimately improving patient outcomes through timely intervention and optimized care.

Exploration of diverse interactions of nonionic poly(vinylpyrrolidone) (PVP) and anionic sodium carboxymethylcellulose (NaCMC) polymers in aqueous imidazolium-based surface active ionic liquid solutions

The binding interactions in complex formation between surface active ionic liquids (SAILs) and polymers (nonionic or anionic) are gaining attention because of their potential applications in novel materials. Therefore, the use of a variety of measurements is required for a better understanding of the interactions involved in polymer/SAIL formation. Here, we have investigated the interactions of nonionic poly(vinylpyrrolidone) (PVP) and anionic sodium carboxymethylcellulose (NaCMC) polymers with SAIL 1-tetradecyl-3-methylimidazolium chloride [C14mim][Cl] in aqueous solution using different measurements such as conductivity, surface tension, fluorescence spectroscopy, dynamic light scattering (DLS) and rheometric measurements. The surface tension, conductivity and fluorescence profiles for SAIL-NaCMC systems provide distinct breakpoints that correspond to four different aggregation states: the concentration at which SAIL monomers begin to attach to the polymer chain (C1), the critical aggregation concentration C2 (cac), the saturation concentration (CS) and the critical micelle concentration (cmc). In the case of SAIL-PVP systems, the surface tension and fluorescence profiles confer three transition states: C2 (cac), CS and cmc and only two transition states have been observed in conductivity curves. The cooperative binding of SAIL to the NaCMC/PVP chain at the solution interface was analyzed by calculating various thermodynamic and interfacial parameters. Strong complexation was observed between NaCMC-SAIL molecules compared to PVP-SAIL systems at the air-solution surface. This is due to the non-ionic character of the PVP chain, which shows weak interactions with SAIL in comparison to NaCMC. Furthermore, DLS and fluorescence measurements were used to investigate the interactions between SAIL and polymers.

UV-Irradiation Effects on the Optical Properties of Polyvinyl Alcohol/Carboxymethyl Cellulose/Polyvinyl Pyrrolidone/Tin Chromium Disulphide Nanocomposite Films for their Application in Optoelectronic Devices

A nanocomposite (NC) film containing polyvinyl alcohol (PVA), carboxymethyl cellulose (CMC) and polyvinyl pyrrolidone (PVP) polymers and tin chromium disulfide (Sn0.75Cr0.25S2) nanoparticles (NPs) was prepared using thermolysis and casting techniques. The prepared NPs were characterized using X-ray diffraction (XRD) and transmission electron microscopy (TEM) techniques. The induced alterations in the optical and color properties of the prepared PVA/CMC/PVP/Sn0.75Cr0.25S2 NC film due to UV irradiation, within fluences ranging from 10 to 80 Joule/cm2 (J/cm2), were characterized via UV spectroscopy and the International Commission on Illumination (CIE) color changes techniques. As the UV fluence increased up to 80 J/cm2, the maximum fluence used, both the direct and indirect bandgaps decreased. We attribute this to the dominance of formed chain crosslinks that destroyed the ordered structure and, thus, increased the amorphous regions. The effect of UV irradiation on the absorbance, refractive index, real and imaginary dielectric parameters and optical conductivity of the NC samples were studied. Furthermore, the optical color changes between the pristine and the irradiated films were evaluated. The pristine NC film was uncolored. It showed significant color changes when irradiated with the UV radiation at increasing fluences up to 80 J/cm2. The changes in the optical properties of PVA/CMC/PVP/Sn0.75Cr0.25S2 NC film suggested its usage as a promising candidate for future optoelectronics characterization techniques.

Transient radical species and oxygen colorimetric indicators grounded on phenothiazinium dyes

This study investigates four phenothiazinium dyes including methylene blue (MB) and three analogues containing auxochrome variation 2–4 as oxygen colorimetric indicators prepared by their incorporation into two types of oxygen permeable materials containing: a) polyvinyl alcohol substrate with additional TiO2 photocatalysts (PhOxIn), and b) carboxymethylcellulose polymer matrix containing glucose and KOH (ChOxIn). In vacuum packages where volumetric concentrations of oxygen were below 0.01 %, the leuco forms of the tested phenothiazinum dyes were readily oxidised, initiating the colour turn from white to blue. The redox processes involved were explored by experimental electron paramagnetic resonance EPR and UV–vis spectroscopic methods and further supported by theoretical quantum chemistry. The EPR experiments showed that the chemical oxidation of the leuco-form of the phenothiazinium dyes 1–4 produced transient aminyl radical species with the single electron mainly located at the nitrogen atom of the heterocyclic core. The formation of these transient aminyl species was also perceived by UV–vis spectroscopy, their absorption maxima situated in the 552–592 nm range being also supported by TD-DFT theoretical calculations.

Fabrication and Characterization of Silver Nanoparticle-Doped Chitosan/Carboxymethyl Cellulose Nanocomposites for Optoelectronic and Biological Applications.

The synthesis of nanoparticles using environmentally friendly methods for applications in fields such as food packaging and biomedicine has been gaining increasing attention. Organic-inorganic nanostructures offer opportunities to create innovative materials suitable for use in optoelectronics and biological applications. In this study, we focused on producing nanocomposite films by blending carboxymethyl cellulose (CMC) and chitosan (CS) polymers in equal proportions (50/50 wt %) and adding silver nanoparticles (Ag NPs) through a solution casting process. Our objective was to examine how the introduction of Ag NPs influenced the structural, optical, mechanical, electrical, and antibacterial properties of the virgin CMC/CS composites. XRD patterns of the prepared samples indicated the presence of crystalline Ag phases within the CMC/CS blend. FT-IR spectroscopy showed the primary vibrational peaks associated with CMC and CS, which exhibited reduced intensity after the addition of Ag NPs. The UV absorption of the nanocomposites exhibited a gradual increase and a shift toward longer wavelengths. The electrical properties are enhanced with higher concentrations of Ag NPs. An increase in the content of Ag NPs resulted in a corresponding enhancement of antibacterial activity against both Staphylococcus aureus and Escherichia coli. The CMC/CS-Ag-doped films demonstrated significant enhancements in Young's modulus (Y), tensile stress (σt), and elongation at break (εB). These findings suggest that these nanocomposite films hold promise for potential applications in optoelectronics and biological fields.

Assessing the Utilization of Sawdust in Water-Based Drilling Fluid for Managing Fluid Loss and Enhancing Viscosity

The evaluation of the use of sawdust in drilling fluid formulation is covered in this study. The investigation focused on the physicochemical and rheological properties of water-based mud (WBM) drilling fluids that included four different dosages of sawdust. These properties included yield stress, plastic viscosity, rheological behavior, gel strength, filtration test (API filtrate; American Petroleum Institute), and pH. The sawdust was employed as a substitute for the polymers commonly used in water-based muds (WBMs) to serve either as a viscosifier or as a fluid loss controller. The current study set out to evaluate how sawdust (diameter ≤630 µm) affected the primary characteristics of the drilling muds. Sawdust was utilized in place of carboxymethyl cellulose polymer (CMC) as a viscosifier and polyanionic cellulose polymer (PAC) as a filtrate reducer at several dosages (0, 10, 20, 50, and 100 g/L). It was found that the sawdust dosage and its role had a significant impact on the rheological characteristics of the drilling fluids. At amounts between 20 and 50 g/L, the sawdust was added as a viscosifier to the drilling fluids under study, resulting in a significant improvement in their physicochemical and rheological parameters (yield stress, plastic viscosity, and gel strength). However, the drilling fluids showed extremely high rheological properties and a viscosity that can slow down fluid circulation in the well when 100 g/L of sawdust were used, totally substituting for the polymers.

Insitu synthesis of gold nanospheres immobilised carboxymethyl cellulose-based conductive hydrogel bioink for 3D bioprinting technology

Electrically conductive bioink (ECB) improves the cellular electrical coupling which increases the propagation of cells in bioprinted 3D scaffolds for developing biomimetic architectures. The preparation of ECB predominantly relies on synthetic organic polymers and inorganic nanomaterials, which have certain limitations such as cytotoxicity, weak mechanical stability, and non-biodegradability. The current study focuses on synthesising an ECB immobilised with gold nanospheres (GNS) within the carboxymethyl cellulose (CMC) polymer to eliminate the drawbacks of ECB preparation. Insitu reduction of gold into stable gold nanoparticles within the CMC hydrogel polymer matrix imparted better conductivity without compromising the bioink properties for 3D bioprinting technology.

The physicochemical properties and molecular docking study of plasticized amphotericin B loaded sodium alginate, carboxymethyl cellulose, and gelatin-based films

Plasticizers are employed to stabilize films by safeguarding their physical stability and avoiding the degradation of the loaded therapeutic drug during processing and storage. In the present study, the plasticizer effect (glycerol) was studied on bioadhesive films based on sodium alginate (SA), carboxymethyl cellulose (CMC) and gelatin (GE) polymers loaded with amphotericin B (AmB). The main objective of the current study was to assess the morphological, mechanical, thermal, optical, and barrier properties of the films as a function of glycerol (Gly) concentration (0.5–1.5 %) using different techniques such as Scanning Electron Microscope (SEM), Texture analyzer (TA), Differential Scanning Calorimeter (DSC), X-Ray Diffraction (XRD), and Fourier Transforms Infrared Spectroscopy (FTIR). The concentration increase of glycerol resulted in an increase in Water Vapor Permeability (WVP) (0.187–0.334), elongation at break (EAB) (0.88–35.48 %), thickness (0.032–0.065 mm) and moisture level (17.5–41.76 %) whereas opacity, tensile strength (TS) (16.81–0.86 MPa), and young's modulus (YM) (0.194–0.002 MPa) values decreased. Glycerol incorporation in the film-Forming solution decreased the brittleness and fragility of the films. Fourier Transform Infrared (FTIR) spectra showed that intermolecular hydrogen bonding occurred between glycerol and polymers in plasticized films compared to control films. Furthermore, molecular docking was applied to predict the binding interactions betweem AmB, CMC, gelatin, SA and glycerol, which further endorsed the stabilizing effects of glycerol in the complex formation between AmB, CMC, SA, and gelatin. The Findings of the current study demonstrated that this polymeric blend could be used to successfully prepare bioadhesive films with glycerol as a plasticizer.

Influence of Battery Electrode Manufacturing Process on Electrode Characteristics and Electrochemical Performance

The numerous battery gigafactory projects show that the Li-ion battery sector is booming. Although groundbreaking technologies such as all-solid-state batteries mobilize a lot of research effort, current Li-ion liquid technology still needs to be updated. Only a few publications are related to electrode manufacturing. However, increasing the active material content, the areal capacity, or the solid slurry content is key to improve the energy density but also the manufacturing costs.The objectives of this thesis work are to understand and improve the preparation of the slurry and the manufacturing process as a whole in order to obtain the best possible performances depending on the material used. Initially, the study is carried out in an aqueous formulation for negative graphite electrodes. Still, it will be extended after that to the positive electrode in an organic formulation. The negative electrode is very interesting from a fundamental study point of view because of its specificities that limit the fast charge operation of the cells with a risk of metallic lithium deposit. This electrode's basic composition, in weight, is 96.5% graphite (90/10 mixture of natural and artificial graphite), 1.3% Na-CMC, 1.7% latex, and 0.5% electronic conductor.Eleven significant parameters were selected thanks to preliminary results and literature outcomes. Their impact is determined by crossing experiences and varying them thanks to a rational approach based on the design of experiments (DOE) methodology. A DOE is carried out to be able to study this large number of parameters with a limited number of trials. Apart from the active material and the mixer used, the parameters are grouped into three categories:- The CMC (CarboxyMethylCellulose) polymer, with the molar mass, the substitution degree, and its content.- The electronic conductors, the content as well as the nature (nanotube, nano-sphere, and platelet)- Electrode properties such as coating speed, porosity, or loading.To determine their influences, characterizations are carried out throughout the electrode coating. The slurries are analyzed by rheology and scanning electron microscopy (SEM). The adhesion of the electrodes and their structuring are measured, with particular attention on the electronic resistivity and tortuosity. Finally, the electrodes obtained are tested by electrochemical cycling at various charging rates.Tortuosity is a particularly sensitive factor in relation to the issue of rapid charge/discharge [1]. The tortuosity is measured by electrochemical impedance in the blocking and symmetric electrode configuration and corresponds to the measurement of the distance traveled by the ions in order to cross an electrode (Figure 1). [2]The results of this wide study will be presented with parameter sensitivity on capacity retention, high charging rate capabilities, or electrode mechanical properties. Interrelations between the parameters will be pointed out. Optimal electrode formulations and designs will be presented to validate the approach.[1] D. Grießl, A. Adam, K. Huber, and A. Kwade, "Effect of the Slurry Mixing Process on the Structural Properties of the Anode and the Resulting Fast-Charging Performance of the Lithium-Ion Battery Cell," J. Electrochem. Soc., vol. 169, no. 2, p. 020531, 2022, doi: 10.1149/1945-7111/ac4cdb.[2] J. Landesfeind, J. Hattendorff, A. Ehrl, W. A. Wall, and H. A. Gasteiger, "Tortuosity Determination of Battery Electrodes and Separators by Impedance Spectroscopy," J. Electrochem. Soc., vol. 163, no. 7, pp. A1373–A1387, 2016, doi: 10.1149/2.1141607jes Figure 1

Facile synthesis of fluorescent carboxymethyl cellulose polymer dots and multi-purpose applications in pH and glucose sensing

Herein, fluorescent carboxymethyl cellulose polymer dots (B-PDs) were synthesized by a straightforward route under mild conditions using ethylenediamine-modified carboxymethyl cellulose (CMC-NH2) and phenylboronic acid as precursors. The B-PDs exhibit a uniform nanoscale size distribution, good water solubility, photostability and excellent fluorescence emission with a high fluorescence quantum yield of 21.6 %. The B-PDs display a reversible fluorescence response with blue emission in acidic solution and green emission in alkaline solution. Moreover, the B-PDs can be designed as an excellent fluorescent sensor for glucose detection. After the addition of glucose, the FL intensity at λex = 388 nm can be enhanced due to the assembly of glucose on the B-PDs based on the reversible reaction between boronic acid and cis-diols through the aggregation-induced enhancement effect (AIE). Two good linear relationships can be obtained between (F-F0)/F0 and the glucose amount ranging from 0 ∼ 0.005 M (R2 = 0.9971) and 0.01 ∼ 1.2 M (R2 = 0.9984), and the detection limit (LOD) was calculated to be 52 μM (3σ/slope). Meanwhile, the proposed probe was successfully utilized to analyze glucose in human urine samples (recovery: 97.9–104.1 %, RSD: 2.64–4.23 %) by the standard addition method, indicating good feasibility as a practical platform for sensing.

Immobilization of hydrochar in cellulose beads for eradicating paracetamol from synthetic and sewage water

Sodium carboxymethyl cellulose polymer was used as a support matrix in immobilizing activated hydrochar derived from bamboo using hydrothermal carbonization. The structural and textural morphology of the beads were studied using FTIR, XRD, SEM/EDS, BET and TGA. Activated hydrochar showed a rough surface with irregular spherical shaped structure. Various oxygenated functional groups in composite beads and activated hydrochar were identified that assist in interaction with PARA pollutant. TGA analysis showed weight loss at three stages 200 °C, 365 °C and 710 °C that leads to complete disintegration of composite beads. BET analysis showed a variation in the surface area between activated hydrochar and beads which could be due to air drying process. Batch adsorption test was conducted for investigating the efficiency of beads in removing PARA from water. Pseudo-second order and Langmuir isotherm fitted the best highlighting chemical mode of adsorption with homogenous interaction on the adsorbent surface. 48.12 mg g−1 was the maximum adsorption capacity estimated from sorption between beads and PARA. For practical applications beads were effectively used in reducing COD levels of PARA spiked sewage water with the defined experimental parameters. Ethanol would be effectively used as regenerating solvent in recycling the beads for the betterment of cost reduction. The activated hydrochar immobilized cellulose beads would be successfully applied as adsorbent in removing target pollutants from water thereby reducing the hurdles faced with respect to fine particles in water treatment.

Polydopamine-Modified Carboxymethyl Cellulose as Advanced Polysulfide Trapping Binder

The search for a high-energy-density alternative to lithium-ion batteries has led to great interest in the lithium sulfur battery (LSB). However, poor cycle lifetimes and coulombic efficiencies (CEs) due to detrimental lithium polysulfide (LiPS) shuttling has hindered its widespread adoption. To address this challenge, a modified sodium carboxymethyl cellulose (CMC) polymer with integrated dopamine moieties and polydopamine nanoparticles was created through a facile one-pot dopamine (DOP) amidation reaction to strengthen noncovalent interactions with LiPSs and mitigate the shuttling effect. The resulting CMC-DOP binder improved electrode wettability, adhesion, and electrochemical performance. Compared to LSBs with a standard CMC binder, CMC-DOP 5:1 (with a 5:1 weight ratio of CMC to dopamine precursor) improves the specific capacity at cycle 100 by 38% to 552 mAh g−1 and CE from 96.8 to 98.9%. LSBs show good stability, even after 500 cycles. Post-mortem electrochemical impedance spectroscopy (EIS) and energy-dispersive spectroscopy (EDS) studies confirmed the effectiveness of the CMC-DOP in confining LiPS in the cathode. This simple but effective nature-inspired strategy promises to enhance the viability of LSBs without using harmful chemicals or adding excess bulk.

Rheological insights on Carboxymethyl cellulose hydrogels

Hydrogels are copiously studied for tissue engineering, drug delivery, and bone regeneration owing to their water content, mechanical strength, and elastic behaviour. The preparation of stable and mechanically strengthened hydrogels without using toxic crosslinkers and expensive approaches is immensely challenging. In this study, we prepared Carboxymethyl cellulose based hydrogels with different polymer concentration via a less expensive physical crosslinking approach without using any toxic crosslinkers and evaluated their mechanical strength. In this hydrogel system, the carbopol concentration was fixed at 1 wt/v% and the Carboxymethyl cellulose concentration was varied between 1 and 5 wt/v%. In this hydrogel system, Carbopol serves as the crosslinker to bridge Carboxymethyl cellulose polymer through hydrogen bonds. Rheological analysis was employed in assessing the mechanical properties of the prepared hydrogel, in particular, the viscoelastic behaviour of the hydrogels. The viscoelastic nature and mechanical strength of the hydrogels increased with an increase in the Carboxymethyl cellulose polymer concentration. Further, our results suggested that gels with Carboxymethyl cellulose concentration between 3 wt/v % and 4 wt/v % with yield stresses of 58.83 Pa and 81.47 Pa, respectively, are potential candidates for use in transdermal drug delivery. The prepared hydrogels possessed high thermal stability and retained their gel network structure even at 50 °C. These findings are beneficial for biomedical applications in transdermal drug delivery and tissue engineering owing to the biocompatibility, stability, and mechanical strength of the prepared hydrogels.

Multi-characteristic tannic acid-reinforced polyacrylamide/sodium carboxymethyl cellulose ionic hydrogel strain sensor for human-machine interaction

Big data and cloud computing are propelling research in human-computer interface within academia. However, the potential of wearable human-machine interaction (HMI) devices utilizing multiperformance ionic hydrogels remains largely unexplored. Here, we present a motion recognition-based HMI system that enhances movement training. We engineered dual-network PAM/CMC/TA (PCT) hydrogels by reinforcing polyacrylamide (PAM) and sodium carboxymethyl cellulose (CMC) polymers with tannic acid (TA). These hydrogels possess exceptional transparency, adhesion, and remodelling features. By combining an elastic PAM backbone with tunable amounts of CMC and TA, the PCT hydrogels achieve optimal electromechanical performance. As strain sensors, they demonstrate higher sensitivity (GF = 4.03), low detection limit (0.5 %), and good linearity (0.997). Furthermore, we developed a highly accurate (97.85 %) motion recognition system using machine learning and hydrogel-based wearable sensors. This system enables contactless real-time training monitoring and wireless control of trolley operations. Our research underscores the effectiveness of PCT hydrogels for real-time HMI, thus advancing next-generation HMI systems.

In vitro evaluation of drying supports and adhesive polymers as adjuvants for biocontrol of Diplodia seriata by Trichoderma harzianum and Clonostachys rosea

Grapevine trunk diseases (GTDs) can cause large losses in vineyards. Diplodia seriata is an important GTD pathogen in Chile. Development and use of bioprotectors is a complementary alternative to the use of agrochemicals for disease management. To produce bioformulations for management of D. seriata, additives could be used to maintain viability and survival of biocontrol agents, such as Trichoderma harzianum and Clonostachys rosea. Effects of drying supports (inulin, maltodextrin, lactose, or talc) and adhesive polymers (carboxymethylcellulose, Aloe vera gel, or chitosan) were assessed on D. seriata conidium viability and mycelium development of T. harzianum and C. rosea, and for their biocontrol capacity against D. seriata. T. harzianum and C. rosea cultured in Potato Dextrose Agar containing inulin (at 10% w/v) maltodextrin (10% w/v), lactose (6% w/v), or talc (4% w/v), or the adhesive polymers carboxymethylcellulose (0.5% w/v), Aloe vera gel (0.5% w/v), or chitosan (1.5% w/v), maintained their biocontrol activity against D. seriata. These additives did not enhance D. seriata development. Therefore, these preparations, at the respective indicated concentrations, can be included in bioformulations for management of disease caused by this pathogen.

Experimental analysis of tribological performance of base ficus carica vegetable oil with different polymers as additives using four ball tribometer

The need to use vegetable lubricants has been driven by the widespread concern for environmental issues, especially in industries that overuse petroleum lubricants. This research examined the tribological characteristics of vegetable-based lubricants by adding additives such as ethylene–vinyl acetate (EVA) and Eichhornia crassipes carboxymethyl cellulose (EC-CMC) polymers to study the viscometric response of the lubricants. The test was conducted using four ball-tester, and analyzed in terms of coefficient of friction (COF), wear scar diameter (WSD), and wear scar rate, respectively. The results showed that with the addition of each additive enhanced the tribological properties significantly but yielded poor results with 0.5% additives for both samples. The characterization investigation showed that ficus carica (Fig) oil responded effectively to the addition of various additives when conducted thermogravimetric analysis (TGA) and Fourier transform infrared (FT-IR) spectroscopy. Under 100 kg load and speed of 1200 rpm, base Fig lubricant yielded a higher COF of 0.193, while blended EVA and EC-CMC gave lower COF of 0.161 and 0.171, while the lowest wear scar diameter was with 1.5 wt% EVA (0.39 mm) and 1 wt% EVA (0.41 mm), respectively. Comparing all the lubricants under 1500 rpm, the base Fig lubricant yielded 0.317, while 1.5 wt% EVA, 1.5 wt% EC-CMC, SEA 5W 30 gives COF of 0.287, 0.263, and 0.239, respectively. The study revealed that the reduction in the COF and wear scar diameter was due to the formation of the film by the included additive.

Investigating the tunable properties of double blended nanocomposite films exposed to direct Nd:YAG laser beam

Detailed characterization for double blended nanocomposite films of PVP (Polyvinylpyrrolidone)/CMC (carboxy-methyl cellulose) polymer blends doped with SnO2 and ZnS nanoparticles based on different proportional concentrations (1-x)SnO2 -x ZnS (x = 0, 0.25, 0.5, 0.75, 1) has been represented. Nanoparticles were synthesized based on the sol-gel technique, while nanocomposite films were prepared using the casting technique. The crystalline structures for both nanoparticles and nanocomposite films before and after laser exposure have been discussed by the x-ray technique. Fourier transform infrared spectroscopic technique (FTIR) revealed variations in the vibrational bands intensities and locations under the effect of both laser exposure and nanoparticles. The morphological features of the studied samples have been discussed through SEM (Scanning Electron Microscope) images. The optical properties (linear-nonlinear) of nanocomposite films have been discussed in details using UV–Vis spectroscopy technique. The refractive index has been calculated based on different proposed models. Similarities in the refractive index values have been observed. The effect of direct laser beam exposure on the estimated values of energy gap Eg has been represented in details. Eg values showed a reduction from 5.1 eV (for undoped films) to 4.8 eV (for laser exposed doped films). Nanocomposite films fully doped with 100% zinc sulphide nanoparticles exhibited the lowest Eg value (4 eV). Linear and nonlinear optical parameters confirmed the dominant effect of direct laser exposure compared with the particle size effect.