Hydroxyethyl Cellulose Concentration Research Articles

Properties and microstructure regulation of electrodeposited ultra-thin copper foil in a simple additive system

Hydroxyethyl cellulose (HEC) has been commonly used in a variety of complex formulations for acid copper plating. However, the roles of HEC acting in acid copper plating still lacks of systematic investigation. To explore the efficacy of HEC in the deposition of the ultra-thin electrodeposited copper foil (ED-Cu), we designed a simple formulation system, in which HEC was used as the single organic additive. Using electron backscatter diffraction (EBSD), microstructures of the prepared ED-Cu was comprehensively investigated. The results showed that the ED-Cu was characterized by a mixed distribution of columnar and equiaxed crystals. Grain morphology, dislocation density and crystal orientation of the ED-Cu could be regulated by HEC concentration. According to the cyclic voltammetry (CV) and chronoamperometry (CA) results, the introduction of HEC between 0–200 ppm led to a polarizing effect, which marginally increased with the HEC concentration. Meanwhile, the increase of HEC concentration enhanced the nucleation rates of copper and reduced the grain size during instantaneous nucleation. The introduction of the HEC also altered the preferred orientation of the ED-Cu foil. Mechanical results showed that the optimum concentration of HEC addition was 125 mg l−1.

Corrosion inhibition of acid pickling –descaling-cleaning action on mild steel using aqueous hydroxyethyl cellulose

The corrosion inhibition capability of aqueous Hydroxyethyl cellulose (HEC) on mild steel corrosion in 1 M HCl solution proposed for mild steel pickling, industrial cleaning, and descaling was evaluated at different concentrations and immersion times using gravimetric measurement. HEC demonstrated efficiency in mild steel corrosion inhibition with a maximum inhibition efficiency of 87% for a 300 ml acid pickling, industrial cleaning, and descaling solution composed of 20% aqueous solution of 0.01 M HEC and 80% of 1 M HCl solution, within an immersion time of 120 hours. The inhibition efficiency was found to increase with the increase in the concentration of HEC implying that HEC’s inhibition action is concentration and time-dependent. The mechanism of adsorption of HEC was identified to be chemisorption with hydroxyl (-OH) moiety donated to the active sites of mild steel coupled with HEC molecules encapsulation of chloride ions on mild steel surface thus preventing the corrosive action of Cl ions on the mild steel.

Sustainable Treatment of Oral Traumatic Ulcers with Licorice Containing Hydrogels: Integrating Computational Modeling, Quality by Design, Green Synthesis, and Molecular Biological Evaluation.

The urge to implement innovative approaches that align with eco-friendly practices and hold promise for enhancing oral health while promoting environmental sustainability has been increasing. This current work aims to develop a sustainable treatment for oral traumatic ulcers using licorice-based hydrogels (LHGs) containing hydroxyethyl cellulose (HEC) as the green gelling agent. Licorice root aqueous extract was phytochemically profiled using UPLC-ESI-MS/MS. Forty-three compounds were detected, with Glycyrrhizic acid being the major component of the extract (34.85 ± 2.77%). By implementing a Quality by Design (QbD) approach, the study investigates the effects of different licorice extract and HEC concentrations on key variables such as pH and viscosity of the prepared formulations, ulcer and wound healing scores, and tissue growth factors via a Full Factorial Experimental Design. The LHGs exhibited desirable consistency, spreadability, and clarity. Statistical analysis, employing an ANOVA test, revealed the high significance of the constructed models with the licorice concentration being the key independent factor affecting all dependent outputs. The pH as well as the viscosity of the prepared LHGs were positively influenced by licorice extract concentration, with higher concentrations leading to increased alkalinity and viscosity. Rheological behavior analysis revealed a pseudoplastic flow with demonstrated thixotropy which is advantageous for application and prolongation of residence time. The wound healing process was assessed through ulcer size, traumatic ulcer healing score (UHS), collagen-1 expression (COL-1), growth factors (EGF, VEGF), pro-inflammatory markers (TNF-α), wound healing score (WHS). LHGs prepared using higher levels of both factors, 30% dried licorice root extract and 4% HEC, demonstrated enhanced wound healing, elevated growth factor expression of 66.67% and 23.24%, respectively, and 88% reduced inflammation compared to the control group, indicating their potential in expediting oral ulcer recovery. Overall, these findings highlight the promising role of green licorice-based hydrogels in promoting sustainable oral mucosal healing.

Miniature and high-performance optical fiber relative humidity sensor based on Fabry-Perot structure interacting with hydroxyethyl cellulose

A miniature Fabry-Perot fiber-optic sensor is demonstrated for high-performance relative humidity (RH) detection. This sensor is constructed by fusing a single-mode fiber to a small section of capillary coating the end with a hydroxyethyl cellulose film (HEC). The effects of capillary length and hydroxyethyl cellulose concentration on the RH response are investigated to obtain the preferential condition with capillary length of 102 μm and HEC concentration of 0.03 g/ml. A testing RH sensitivity of 1.24 nm/%RH can be achieved in the range of 48%RH to 60%RH. Simultaneously, small hysteresis errors are demonstrated in the tests with increasing and decreasing RH values. The dynamic measurements reveal a response time of 1.61 s and a recovery time of 2.1 s. The high sensitivity, good stability and simple fabrication process of the sensor make it promising for practical applications of relative humidity sensors.

Wet-spinnability and crosslinked Fiber properties of alginate/hydroxyethyl cellulose with varied proportion for potential use in tendon tissue engineering

Researchers have examined different bio-inspired materials in tissue engineering and regenerative medicine to fabricate scaffolds to address tendon regeneration requirements. We developed fibers based on alginate (Alg) and hydroxyethyl cellulose (HEC) by wet-spinning technique to mimic the fibrous sheath of ECM. Various proportions (25:75, 50:50, 75:25) of 1 % Alg and 4 % HEC were blended to this aim. Two steps of crosslinking with different concentrations of CaCl2 (2.5 and 5 %) and glutaraldehyde (2.5 %) were used to improve physical and mechanical properties. The fibers were characterized by FTIR, SEM, swelling, degradation, and tensile tests. The in vitro proliferation, viability, and migration of tenocytes on the fibers were also evaluated. Moreover, the biocompatibility of implanted fibers was investigated in an animal model. The results showed ionic and covalent molecular interactions between the components. In addition, by properly maintaining surface morphology, fiber alignment, and swelling, lower concentrations of HEC in the blending provided good degradability and mechanical features. The mechanical strength of fibers was in the range of collagenous fibers. Increasing the crosslinking led to significantly different mechanical behaviors in terms of tensile strength and elongation at break. Because of good in vitro and in vivo biocompatibility, tenocyte proliferation, and migration, the biological macromolecular fibers could serve as desirable tendon substitutes. This study provides more practical insight into tendon tissue engineering in translational medicine.

Development of Besifloxacin HCL Loaded Ocular İn Situ Gels; In Vitro Characterization Study

Objective: The aim of this study is to develop in situ gel formulations containing besifloxacin hydrochloride are heat triggered, which are prepared by using different poloxomer and derivatives different polymers that will change the gelling temperature to increase corneal contact time, regulate drug release, improve ocular bioavailability and increase patient compliance increase mucoadhesion.
 Material and Method: Various concentrations of poloxamer 188 (P188) and poloxamer 407 (P407) were used to create the in situ forming gels. To increase the gel's capacity for bioadhesion, mucoadhesives such hydroxypropylmethyl cellulose (HPMC) or hydroxyethyl cellulose (HEC) were included in the formulations. Drug release in vitro, sol-gel transition temperature, rheological behavior, pH, clarity, and mucoadhesion force were all assessed for the produced formulations. 
 Result and Discussion: The developed formulations' gelation temperatures ranged from 29 to 35°C. The preparations' viscosity and mucoadhesion force increased with increasing P407, HPMC, and HEC concentrations. Besifloxacin HCl forms in situ gel formulas with K1, K2, K3, and K6 suited for mucoadhesion characteristics, gelation temperature, and viscosity. These formulations exhibit pseudoplastic flow. Increasing polymer concentrations resulted in a reduction in the burst release of the formulations. However, at the end of 6 hours, drug release was finished in all formulations. The results show that in situ gels containing P407 and P188 show promise for besifloxacin HCl application

Evaluation of the effect of maltodextrin and hydroxyethyl cellulose solution containing ZnO and Fe2O3 nanoparticles on the CO2 release in sodium bicarbonate coating process

Coating is a rapidly extending technology; especially in food and pharmaceutical industries. The coating process of sodium bicarbonate using ZnO and Fe2O3 nanoparticles (NPs) in aqueous solutions of maltodextrin (MD) and hydroxyethylcellulose (HEC) as wall materials has been studied in this work. The best operating conditions obtained by factorial design were the fluidization air flow rate of 100 m3/h, spraying pressure of 4 bars, drying air temperature of 60 °C, MD concentration of 30 % and HEC concentration of 0.1 %. The introduction of the NPs into the coating solution provides a heterogeneous surface, which enforces the wall material to a more uniform and faster crystallization. The applied conditions have been shown to be efficient for the coating process investigated in this study since they improve the coating characteristics such as CO2 release reduction, which is the most important one. CO2 release was reduced from 4 % for coated powders with no NPs in the coating solution to 2.4 % and 3.5 % for coated powders with Fe2O3 and ZnO NPs in the coating solution, repectively. The adsorption–desorption of N2 gas implies that the pore sizes of the coating layer surface have been significantly decreased by adding NPs to the coating solution.

Colloidal and rheological properties of natural rubber latex concentrated with hydroxyethyl cellulose and sodium dodecyl sulphate

AbstractNatural rubber latex (NRL) is a complex colloidal system composed of rubber particles surrounded by a layer of phospholipids and proteins maintaining its colloidal stability. NRL creaming is a nonrobust concentration method, and its colloidal and rheological properties can be altered due to the presence of creaming agents and surfactants. Both properties must remain stable over time after creaming to ensure conditions for subsequent manufacturing processes. These properties have been evaluated for synthetic latex, but not for NRL in which the clone variety and phenological factors make the system being always different. In this research, hydroxyethyl cellulose (HEC) and sodium dodecyl sulphate (SDS) are used to concentrate NRL and response surface methodology was selected to optimize the colloidal and rheological properties of creamed NRL. Flocculation and stabilization by depletion are involved on NRL concentration depending on HEC and SDS concentration. Those agents modify NRL zeta potential in a range of −78 and −63 mV, and viscosity increases more than 10 times the raw NRL value. SDS plays a key role on enhancement of the creaming process and in electrostatic stability because its anionic nature. Physicochemical interactions between NRL, HEC, and SDS are proposed.

Exploring the gelation of aqueous cellulose nanocrystals (CNCs)-hydroxyethyl cellulose (HEC) mixtures

We investigated the gelation and microstructure of cellulose nanocrystals (CNCs) in nonionic hydroxyethyl cellulose (HEC) solutions. Cellulose nanocrystals (CNCs) with a particle length of 90 nm and width of 8 nm currently produced by acid hydrolysis of wood pulp were used in this study. The microstructures of CNCs/polymer suspensions were investigated by performing linear small amplitude oscillatory shear (SAOS) and nonlinear large amplitude oscillatory shear (LAOS), in addition to constructing CNCs phase diagrams and measuring steady-state shear viscosities. Significant viscosity increases at low shear rates coupled with high shear thinning behaviors were observed in CNCs in HEC solutions above the overlapping concentration of HEC. The physical strength of CNCs/HEC solution gels increased with the increase in CNCs concentration and resembled the weakly crosslinked gels according to the scaling of linear dynamic mechanical experiments. According to LAOS analysis, CNCs/HEC mixtures showed type III behavior with intercycle stress softening, while the samples showed stress stiffening in single cycles.Graphical abstract

Hydroxyethyl Cellulose As a Rheological Additive for Tuning the Extrusion Printability and Scaffold Properties.

Bioink, a key element of three-dimensional (3D) bioprinting, is frequently engineered to achieve improved printing performance. Viscoelasticity related to rheological properties is correlative of the printability of bioink for extrusion bioprinting, which affects the complexity of printing 3D structures. This article shows the use of hydroxyethyl cellulose (HEC) as a rheological additive for engineering bioink to improve the printability without reducing the biocompatibility. Different concentrations of HEC were added to four types of bioink, namely, reagent-crosslinked, temperature-dependent phase change, ultraviolet-polymerized, and composite hydrogel bioinks, to investigate the effect on the viscoelasticity properties, print fidelity, and other printed scaffold properties. The results indicate that HEC is able to increase the rheological properties by 100 times to stabilize complex structures and improve the printing fidelity to narrow the gap between the design value and theoretical value, even converting nonviscous ink into directly printable ink, as well as tune the swelling ratio for better molecular permeability. The degradation of bioink can also be tuned by the addition of HEC. Moreover, this bioink is biocompatible for cell lines and primary cells. HEC is expected to be widely used in 3D extrusion-based bioprinting.

PEMANFAATAN POTENSI LIMBAH KULIT BAWANG MERAH (Allium Cepa. L) SEBAGAI SEDIAAN GEL HAND SANITIZER

The increased health problems caused by microorganisms at the hands, hand sanitizer gel as the way out to maintained health and hand hygiene because it is more practical and easy to carry. The purpose of this study was to make formulations of gel with physically stable and had inhibitory activity against the Staphylococcus aureus bacteria. In this study three formulations were made with a ratio of Hydroxy ethyl selilulose 0.5% (F1), 1% (F2) and 2% (F3) then physical stability testing included organoleptic, homogeneity, pH and dispersion before and after accelerated storage, then antimicrobial activity by sump method. Organoleptic test showed there is no color, smell and texture changes. The results of the homogenety test, formula with concentration of Hydroxy ethyl cellulose 1% and 2% is homogeneous. The pH test results showed that the gel preparation did not change pH. Dispersing test showed concentration hydroxyethyl cellulose 1% has the highest dispersion value. but statistical paired T test results showed that the dispersion before and after storage was accelerated significantly different 0.043 (p <0.05), but still in accordance with the range of dispersion specifications for a good semisolid preparation.The MIC test results showed Formulation F1, F2 and F3 ethanol extract red onion skin gel are strong inhibitory effect, ethanol extract of red onion skin gel F1 inhibitory zone is 16mm, F2 and F3 had the same inhibitory zone is 14.33. It can be concluded F2 has the best physical stability, but F1 is the most effective to inhibit Staphylococcus aureus.
 

Shelf-life of guavas coated with biodegradable starch and cellulose-based films

Guava is a perishable fruit susceptible to post-harvest losses. So, the development of biodegradable films based on acetylated cassava starch (ACS) and hydroxyethyl cellulose (HEC) could be an alternative to increase guavas (Psidium guajava L.) shelf life. Films were characterized by solubility, opacity, water vapor transport, and thickness. Mass loss, texture, titratable acidity, soluble solids, vitamin C, and skin color of the fruits were analyzed. The films with higher HEC concentration were more transparent and hygroscopic. Guava coated with 75% HEC and 25% ACS or 100% HEC films increased firmness, maintained green skin color and reduced ripeness, lasting for 13 days, ensuring that the ACS and HEC based films can increase guavas shelf life, besides decrease environmental impacts of non-biodegradable packages.

Separation of subcellular fluorescent microspheres by capillary electrophoresis.

Fluorescent microspheres (FMs) are widely employed in diagnostics and life sciences research; here, we investigated the effect of capillary coating, polymer concentration, electric field strength, and sample concentration on the separation performance of 1.0μm FMs in hydroxyethyl cellulose (HEC) by capillary electrophoresis (CE). Results showed that (1) capillary coating could enhance the fluorescence signal. (2) For HEC with the same molecular weight, the higher HEC concentration is, the later the first peak appears in the electropherogram. (3) When FMs are diluted, increasing the electric field strength can enhance the migration speed and reduce the aggregation of FMs. (4) The number of FMs calculated is close to the theoretical value when it is diluted 10,000 times. The optimum conditions for CE were as follows: 6cm/8cm of effective length and total length of the coated capillary, 0.3% HEC (1300k), and 300V/cm of electric field strength. Such a study is helpful for the development of a FM counting system. Graphical abstract.

Developing a Physically Cross-Linked Hydroxyethyl Cellulose Hydrogel for Wound Dressing Applications

Physically cross-linked hydroxyethyl cellulose (HEC) hydrogels of different concentrations are synthesized at room temperature, and the hydrogel films are evaluated for its antimicrobial and exudate absorption properties. Results showed that all the hydrogels inherently possess antimicrobial property for all the HEC concentrations tested. The maximum water uptake is determined to be 173.8% for the 13.75% HEC hydrogel. At the same HEC concentration, the hydrogel absorbed the largest amount of exudate. The rate of diffusion in the longitudinal direction is observed to be higher, but the exudate was observed to travel generally farther in the radial direction. The diffusion coefficient model reported by Kipcak, et al. in 2014 was observed to be valid and applicable for the HEC hydrogels. Lastly, scanning electron microscopy showed the microstructure of the fibers and pores of the hydrogels.

Hydroxyethyl cellulose as a rheology modifier for water-based drilling fluids formulated with Algerian bentonite

Under the different geological conditions of wells and during the drilling operation, some of the water-based drilling fluid compositions are sometimes not efficient for the drilling success of the oil and gas wells (case of the Algerian oil and gas wells). In the use of bentonite in drilling fluid applications, the addition of hydroxyethyl cellulose (HEC) is recommended to obtain good rheological properties of the fluid. In this research, we investigate the rheological behaviour in steady state, and dynamic shear rheology of drilling fluids formulated based on an Algerian bentonite with a fixed concentration of 3 wt% and a water-soluble polymer HEC of high molecular weight (~ 9.5 × 105 g/mol) at different concentrations ranged from 0.02 to 0.2%. All the results obtained by a controlled stress rheometer have been commented by taking the interaction between the clay and the polymer molecules into consideration, to highlight the effect of HEC on the rheological properties of bentonite suspensions. Herschel–Bulkley (H–B) model was used to fit and interpret the experimental data. A significant increase in the rheological properties of the mixture bentonite–HEC with the increase in HEC concentration has been shown. These properties reached the maximum at HEC concentration of 0.1 wt%; beyond this value, they decreased. X-ray diffraction test performed on the different samples also allowed understanding the rheological behaviour of the system bentonite–HEC. Indeed, the HEC could intercalate the bentonite interlayer and formed link bridges between bentonite particles below a critical concentration of 0.1 wt%. Based on the results of the study, it is recommended to choose the optimum concentration of HEC to be added to the bentonite suspension to ensure the optimum rheological characteristics of the drilling fluids.

Effects of HEC Concentration on Silicon Polishing

Hydroxyethyl cellulose (HEC) is believed to effectively reduce haze level in silicon final polishing. We find that the removal rate(RR) and roughness of the polishing are very sensitive to the concentration of HEC, which can be divided into two concentration ranges. Its machanism is not only absorption occurence on silicon surface but also related to HEC colloid properties. Evidence has shown that HEC covers on the surface of silica sol, and there are three forms of coverage depending on the concentration, which have different effects on the interface between silicon and abrasive during polishing. Combined with steric hindrance, a possible polishing model is discussed based on the existence of HEC which is verifed by coeffiecient of friction force(CoF) according to HEC concentration. The results not only provide guidance for effective silicon polishing, but also imply that colloidal properties of additives with surface activity should be considered in other polishing systems.

Rheological studies and optimization of Herschel–Bulkley parameters of an environmentally friendly drilling fluid using genetic algorithm

The Herschel–Bulkley rheological parameters of an environmentally friendly drilling fluid formulated based on an Algerian bentonite and two polymers—hydroxyethyl cellulose and polyethylene glycol—have been optimized using a genetic algorithm. The effect of hydroxyethyl cellulose, temperature, pH and sodium chloride (NaCl) on the three-parameter Herschel-Bulkley model was also studied. The genetic algorithm technique provided improved rheological parameter characterization compared to the nonlinear regression, especially in the case of drilling fluids formulated with sodium chloride making it a better choice. Furthermore, the oscillatory test offered more reliable yield stress values. The rheological parameters were found to be very sensitive to different conditions. Yield stress and consistency index increased with increasing the hydroxyethyl cellulose concentration, reaching maximum at a temperature of 65 °C and decreased with decreasing pH and also when adding sodium chloride to the drilling fluid. The flow index changed inversely to yield stress and consistency index. The physical origins of these changes in rheological parameters were discussed and correlation between variation in rheological parameters and bentonite suspension properties were concluded. Based on these results, it is recommended to use the proposed formulation of drilling fluid at high temperature and when the formation of alkaline pH is encountered due to the gelation mechanism and to select the optimum concentration of NaCl to avoid degradation of the rheological parameters.

The rheological behaviour of a water-soluble polymer (HEC) used in drilling fluids

The rheological properties of drilling fluids have been always considered as critical aspects to the success of drilling operations; in this fact, the control of these properties was of paramount importance. In this paper, the rheological behaviour of a water-soluble polymer, namely hydroxyethyl cellulose (HEC) used in drilling fluids, was investigated. Steady-state shear rheology and frequency experiment were carried out on the sample at different concentrations ranging from 0.1 to 1.2 wt% and constant temperature of 25 ± 0.1 °C using a controlled-rate rheometer. The HEC solutions showed a shear thinning behaviour that was successfully fitted using the Cross model, where its parameters were found to increase with the HEC concentration. The steady-state shear rheological data allowed determining the intrinsic viscosity of the polymer (~ 15.05 dl/g) in distilled water; thereafter, an estimation of the molecular weight of HEC using the Mark–Houwink equation indicated that the studied sample was of high molecular weight (9.5 × 105 g/mol), which gave it good rheological properties for drilling fluid applications. The critical overlap concentration was found to be ~ 0.24 wt% using two methods, the intrinsic viscosity and the plot of the apparent viscosity versus the polymer concentration at specific shear rate. The frequency sweep measurements allowed confirming the viscoelastic behaviour of the polymer; HEC solutions behaved either as viscous or as elastic materials at low and high frequencies, respectively. This information is essential for mud engineers to develop and maintain the properties of drilling fluid to the required specifications.

Study on the Mechanism of Micro-Defect Reduction during Si Final Polishing with Water-Soluble Polymers

The effect of water-soluble polymer in alkaline slurry on the micro-defect during Si final polishing was investigated. With the concentration of hydroxyethyl cellulose (polymer A) 0.15wt% and polyoxyethylene ether (polymer B) 0.05wt%, Haze value and the number of micro-defects (larger than 120nm) were reduced to 0.01 ppm and 7, respectively, on a 300mm silicon wafer surface. Also, the surface roughness was reduced from 17.2 to 0.153nm. Through the comprehensive analysis of slurry viscosity and Zeta Potential measurement, the mechanism of water-soluble polymers for micro-defect reduction during Si final polishing was discussed. Polymer B coated on the surface of SiO2 particle forming a “soft shell”, which functions as a “soft abrasive” and thus reduces friction between wafer surface and slurry abrasives. As for polymer A, the O atomic of -OH group in polymer A molecular could combine with Si-H bond on the surface of silicon wafer to form the hydrogen bond, like Si-H…O bond. As such, polymer A can be adsorbed on the surface of the silicon wafer to form a hydration film, which also can reduce friction between wafer surface and slurry abrasives/pad asperities. With the joint action of polymer A and polymer B, as experimental results showed, the number of micro-defects and Haze value in Si final polishing process can be significantly reduced.

Dispersion of carbon fibers and conductivity of carbon fiber-reinforced cement-based composites

Abstract Dispersion of carbon fibers in the cement matrix remains a hot topic in the preparation of carbon fiber-reinforced cement-based composites (CFRC) because it affects greatly both the mechanical and electrical properties of the composites. In this work, a new dispersant hydroxyethyl cellulose was used with the aids of pre-dispersion by ultrasonic wave to realize the uniform distribution of chopped carbon fibers in the cement matrix. The fracture surface of the prepared CFRC was observed by scanning electron microscopy, the elemental distribution was investigated by energy dispersive spectroscopy, and the components was analyzed by X-ray diffraction. Influences of carbon fiber lengths and contents, water/cement weight ratio, molding process, curing time, and silica fume content over the conductivity of the CFRC composites were studied. The mechanism of conductivity was discussed. Results shown that the electrical resistivity intended to decrease with the increasing of carbon fiber contents. The mass fraction 0.6% of carbon fibers was a turning point. The concentration of hydroxyethyl cellulose between 1.66% and 1.86% was mostly beneficial for the dispersion of carbon fibers. The resistivity was increased first and decreased then with the increase of water/cement ratio. When the CFRC sample was prepared by the vibrating pressing method, the resistivity of the sample was reduced far greatly than that of the sample by the vibrating method. The incorporation of silica fume into the CFRC composites exerted not only a good effect on the dispersion of carbon fibers, but also increased the density of the composites to further influence the conductivity of the CFRC.