Ethyl Cellulose Content Research Articles

Incorporation of bioactive compounds from avocado by-products to ethyl cellulose-reinforced paper for food packaging applications.

Reinforced films were fabricated by impregnating paper in ethyl cellulose solutions. After solvent evaporation, the infused ethyl cellulose acted as binder of the paper microfibres and occupied the pores and cavities, thus improving the mechanical and barrier properties. To prepare active films, avocado by-products from guacamole industrial production were extracted in ethyl acetate. Then, the extract (optimized to be rich in phenolic compounds and flavonoids and mainly composed by lipids) was incorporated to the paper reinforced with the highest content of ethyl cellulose. In general, the addition of the avocado by-products extract decreased the water uptake and permeability, improved the wettability, and increased the biodegradability in seawater and the antioxidant capacity. In addition, these films acted as barriers and retainers for Escherichia coli and Bacillus cereus. The potentiality of these materials for food packaging was demonstrated by low overall migrations and a similar food preservation to common low-density polyethylene.

Formation and characterization of konjac glucomannan/ethyl cellulose films by using ethanol and water as the solvents

Hydrophilic konjac glucomannan (KGM)/hydrophobic ethyl cellulose (EC) film was prepared in the ethanol/water environment. The film-forming solution and film properties were both characterized to analyze the molecular interaction changes. Although higher ethanol usage enhanced the stability of the film-forming solution, it did not benefit the film property improvement. The SEM images showed some fibrous structure on the air surface of the films, consistent with the XRD results. The changing trend of mechanical properties and the FTIR results suggested that both ethanol content and ethanol evaporation impacted the molecular interaction during the film formation. The surface hydrophobicity results indicated that the ethanol content could cause significant EC aggregation changes on the film surface only with high EC contents. The water vapor permeability results suggested that higher ethanol usage decreased the compactness of the films. Considering all results, the 20 % ethanol content and the weight ratio of KGM: EC = 7:3 were suggested for the film preparation due to the superior properties in most properties. This study contributed to the understanding of polysaccharide interaction in the ethanol/water environment and offered an alternative biodegradable packaging film.

Impact of ethyl cellulose variation on microstructural and electrochemical properties of spin coated YSZ electrolyte thin films for SOFCs: Slurry composition evolution

The present work meticulously highlights the physical and electrochemical properties of slurry spin coated Yttria Stabilized Zirconia (YSZ) electrolyte thin films for solid oxide fuel cell (SOFC) applications wherein the concentration of ethyl cellulose (EC) is varied from 3.5 wt% to 6.5 wt% in the EC/YSZ/terpineol slurry. The TGA of the prepared mixtures reveals the complete mass removal of EC in temperature range of 380–400 °C. The dense and crack-free YSZ thin films on NiO/YSZ anode composites are developed by performing four separate coating cycles where each cycle is preceded by baking the films at 380 °C. The prepared YSZ electrolyte thin films showed polycrystalline nature with cubic phased prominent reflection corresponding to plane (111). The crystallite size of YSZ thin films is determined from W–H and Scherrer's relations which is obtained in the range of 18–26 nm and 21–26 nm, respectively. The 3D AFM projection shows hill-like topography where the average roughness is found to be increased from 3.01 nm to 8.49 nm with an increase in the EC content. FESEM analysis unveils smooth morphology along with the presence of some abscission zones in YSZ thin films after the removal of EC. The electrochemical properties are explored by fitting equivalent electrical circuit to the Nyquist data which confirms electrolytic response of the prepared coatings. The thermal activation of ionic conduction has been verified by observing the Arrhenius plots where conductivity is found to be varied in range 10 −4 -10 −5 S/cm with the respective increase in EC content. The activation energies of YSZ electrolyte thin films are found to be in the range of 1.09–1.18 eV which are slightly higher as compared to that of bulk YSZ.

Preparation and Performance of Microencapsulated Sealing Material for Coal Mine Gas Drainage.

The performance of coal mine gas extraction borehole sealing material plays an essential role in the efficiency of gas extraction. Microcapsule technology was proposed to delay the expansion time of sealing materials to address the ineffective expansion of cement-based sealing materials in hydration. Based on conventional cement-based sealing materials, delayed-expansion microcapsules were prepared by phase separation with ethyl cellulose (EC) as the capsule wall material and montmorillonite (MMT) as the core material. A single-factor experiment showed that the delayed-expansion microcapsule had the best comprehensive effect when the EC content was 3%, the stirring rate was 400 rpm, the MMT content was 3.5%, and the core-wall ratio (CWR) was 10:3. Second, the slow release effect of the cement samples under the action of microcapsules is remarkable through physical tests. In addition, the triaxial compression test results show better mechanical properties of the delayed-expansion sealing materials. Then, nuclear magnetic resonance scanning was applied to the coal samples injected with different sealing materials. It was found that the proportions of macropores and mesopores in the total pore volume in the coal sample at 50 and 100 mm from the borehole wall decreased by 12.28 and 11.82%, respectively, indicating that the delayed-expansion sealing material has a better sealing effect.

Impact of the Morphology of Electrospun Lignin/Ethylcellulose Nanostructures on Their Capacity to Thicken Castor Oil.

This study reports on a novel strategy for manufacturing thickened gel-like castor oil formulations by dispersing electrospun lignin/ethylcellulose nanostructures. These thickened formulations were rheologically and tribologically evaluated with the aim of being proposed as alternative ecofriendly lubricating greases. Low-sulfonate kraft lignin (LSL) and ethylcellulose (EC) were dissolved in a DMAc:THF mixture at different concentrations (8, 10, and 15 wt.%) and LSL:EC ratios (50:50, 70:30, and 90:10) and subjected to electrospinning. The resulting electrospun nanostructures were morphologically characterized. EC acting as the cospinning polymer improved both LSL spinnability and the oil structuring ability. Solutions with a high lignin content achieved microsized particles connected by fibrils, whereas solutions with a high EC content (50:50 ratio) and LSL/EC total concentration (10 and 15 wt.%) yielded beaded or bead-free nanofibers, due to enhanced extensional viscoelastic properties and nonNewtonian characteristics. The gel-like properties of electrospun nanostructure dispersions in castor oil were strengthened with the nanostructure concentration and the EC:LSL ratio, as a result of the formation of a more interconnected fiber network. The oleodispersions studied exhibited a satisfactory frictional response in a tribological contact, with friction coefficient values that were comparable to those achieved with traditional lithium-lubricating greases.

Characterizing the rheological properties of ethylcellulose-beeswax oleogel to enhance carotenoids stability

The objectives were to study the optimum content of ethyl cellulose (EC) based on rheological properties and to reduce the degradation of the bioactive substances applied in the solid-lipid cosmeceutical production of lip balm. EC contents of 0–7% w/w and beeswax were used as oleogelators while gac (Momordica cochinchinensis) oil was the source of the bioactive substances. A higher percentage of EC caused the oleogel to become more solid-like. However, the optimal EC content should be in the range from 5 to less than 7%, since at 7% the product seemed to be too dry and too stiff. After storage for 3 mth at room temperature in an opaque container, the oleogel at 5%EC had the significantly highest lycopene and beta carotene contents at 11.61 ± 0.82 and 81.38 ± 3.02 mg/100 g sample, respectively, among samples added with EC 0–7% and the highest antioxidant capacity of 763.11 ± 116.16 mg ascorbic acid equivalents (AAE)/100 g sample.

Tuning the Sensitivity and Dynamic Range of Optical Oxygen Sensing Films by Blending Various Polymer Matrices.

In this work, eight different types of optical oxygen sensing films were prepared by impregnating indicator and matrix solution on the surface of a polypropylene microporous filter membrane. The polymer matrix of the sensing films was ethyl cellulose (EC), polymethyl methacrylate (PMMA), and their blends with different mixing ratios. Scanning electron microscopy (SEM), laser confocal microscopy, and fluorescence spectrometer were used to investigate the morphologies and optical properties of the sensing films. Phase delay measurements under different oxygen partial pressures (PO2) and temperatures were applied to investigate the analytical performances of the sensing film for gaseous O2 monitoring. Results show that the response time of all the sensing films was extremely fast. The sensitivities and dynamic ranges of the sensing films with the blended polymer matrix were separately decreased and increased as the EC/PMMA ratio decreased, and the S-V curve of the sensing films blended with equal content of EC and PMMA exhibited good linearity under different temperatures, showing a promising prospect in practical application.

Expert Design and Optimization of Ethyl Cellulose-Poly (ε-caprolactone) Blend Microparticles For Gastro-Retentive Floating Delivery of Metformin Hydrochloride.

Metformin Hydrochloride (MH) is an oral anti-hyperglycemic agent belonging to the biguanide class of drugs. The present study involves the formulation and evaluation of gastro-retentive floating microparticles containing MH as a model drug for the prolongation of absorption time. Three levels of a three-factor, Box-Behnken design were used to evaluate the critical formulation variables. Microparticles were prepared using a water-in-oil-in-water double-emulsion solvent evaporation method and examined in terms of production yield, particle size, entrapment efficiency, floating ability, morphology, FTIR (Fourier transform infrared spectroscopy), and in vitro drug release. The optimum conditions for preparing MH microparticles were predicted to be the content of ethyl cellulose content (150 mg),poly (ε-caprolactone) (150 mg), and polyvinyl alcohol (1%w/v).The optimized MH microparticles were found to be spherical with a mean size of 350.2 µm. Entrapment efficiency was 58.62% for microparticles. 63.94% of microparticles showed floating properties. The FTIR analysis confirmed no chemical linkage between microparticle components. in vitro release study showed a controlled release for up to 8h. These results demonstrated that MH microparticles, as a drug delivery system, may be useful to achieve a controlled drug release profile suitable for oral administration and may help to reduce the dose of the drug and to improve patient compliance.

Development of behenic acid-ethyl cellulose oleogel stabilized Pickering emulsions as low calorie fat replacer

This study investigated the optimization of thermal, functional and rheological properties of Ethyl Cellulose (EC)-based oleogel considering different concentrations of Behenic Acid (BA) and stability of water in oleogel (w/og) emulsions. The results showed that the combination of EC and BA improved the oleogel properties at specific ratios (2:4 and 1:5 wt%). High strength (G′ > 1000 mPa) with good thermo-responsive and viscoelastic behavior in the range of 45–60 °C and low loss of oil (<0.2%) were observed in these oleogel formulations. Polarized light microscopy images and XRD results showed the presence of crystals and high proportion of crystalline regions in the mentioned formulations. There were no significant differences among solid fat content (SFC) of EC contained oleogels. The FTIR results indicated new hydrogen bonds formation. The w/og stabilized emulsions with EC: BA (1:5 wt%) oleogel showed high physical stability even at high ratios of disperse phase (5 to 45 wt% of water). The particle size and polydispersity index (PDI) of emulsions were reduced significantly to 250 nm and 0.19, respectively by increasing the ratio of water phase to 45:55 w/og. The oleogel and developed Pickering w/og emulsion has good potential in the formulation of low calorie food products.

Direct ink writing of 3D-Honeycombed CL-20 structures with low critical size

3D-Honeycombed CL-20 structures with low critical size of detonation have been fabricated successfully for intelligent weapon systems using a micro-flow direct ink writing (DIW) technology. The CL-20-based explosive ink for DIW technology was prepared by a two-component adhesive system with waterborne polyurethane (WPU) and ethyl cellulose (EC). Not only the preparation of the explosive ink but also the principle of DIW process have been investigated systematically. The explosive ink displayed strong shear-thinning behavior that permitted layer-by-layer deposition from a fine nozzle onto a substrate to produce complex shapes. The EC content was varied to alter the pore structure distribution and rheological behavior of ink samples after curing. The deposited explosive composite materials are of a honeycombed structure with high porosity, and the pore size distribution increases with the increase of EC content. No phase change was observed during the preparation process. Both WPU and EC show good compatibility with CL-20 particles. Apparently high activation energy was realized in the CL-20-based composite ink compared with that of the refined CL-20 due to the presence of non-energetic but stable WPU. The detonation performance of the composite materials can be precisely controlled by an adjustment in the content of binders. The 3D honeycombed CL-20 structures, which are fabricated by DIW technology, have a very small critical detonation size of less than 69 μm, as demonstrated by wedge shaped charge test. The ink can be used to create 3D structures with complex geometries not possible with traditional manufacturing techniques, which presents a bright future for the development of intelligent weapon systems.

Controlled-release urea encapsulated by ethyl cellulose/butyl acrylate/vinyl acetate hybrid latex

Abstract Fertilizer encapsulation through polymer membranes can reduce fertilizer losses and minimize environmental pollution. In this paper, an emulsion of ethyl cellulose (EC)/vinyl acetate (VAc)/butyl acrylate (BA) was successfully prepared by pre-emulsified semi-continuous seed emulsion polymerization. EC/BA/VAc films showed biodegradability. The influence of the EC content on the properties of EC/BA/VAc films was also investigated by DSC, a water absorbency analysis, etc. Controlled-release urea encapsulated by EC/BA/VAc latex was prepared in a film coating machine and conformed to the standards for slow-release fertilizers of the Committee of European Normalization. The release of urea from controlled-release urea encapsulated by EC/BA/VAc latex containing 0%, 5%, 10%, and 15% EC was 75.1%, 65.8%, 70.1% and 84.1%, respectively, after 42 days, and controlled-release urea encapsulated by EC/BA/VAc latex (5% EC) had the best controlled-release ability. Therefore, controlled-release urea encapsulated by EC/BA/VAc latex has many potential applications in agricultural industry.

The effect of the ink composition on the performance of carbon-based conductive screen printing inks

Conductive carbon-based screen printable inks are used in a wide range of applications. The aim of the comprehensive study was to monitor how the fundamental components affect the ink performance. In the present work there were prepared several variants of carbon-based inks. The higher ratio of carbon black in the graphite (G):carbon black (CB) mixture, and also the higher total carbon amount have been confirmed to cause an increase in viscosity in the shear rates range from 200 to 1000 s−1. The lowest sheet resistance values were observed with 3:1 G:CB ratio. Increasing of the total carbon amount from 15 to 35 wt% has led to improvement in conductivity with final value of 32.4 Ω sq−1. The increasing ratio of lower boiling point solvents (4-hydroxy-4-methyl-2-pentanone, ethyl alcohol) has led to the improvement of the sheet resistance (lowest value of 22.73 Ω sq−1), while the roughness values increased. In the case of rheological properties evaluation, the ethyl cellulose content modification (increase from 2 to 10 wt% in the binder) resulted in increasing viscosity dependencies. In addition, the increase of the ethyl cellulose content had minimal impact on the roughness, but positive impact on the conductivity. On the other hand, it was identified an unobvious trend after modifying the binder by polyvinylpyrrolidone. To achieve the desired effect on the sheet resistance, volume resistivity and roughness of the printed layers it is necessary to specify the most proper ethyl cellulose:polyvinylpyrrolidone ratio. The main reason is the interaction between the two polymers within the binder.

A novel limiting current oxygen sensor prepared by slurry spin coating

La0.7Sr0.3MnO3 (LSM) and Y0.08Zr0.92O2 (8YSZ) were synthesized by citric-nitrate and co-precipitation methods, respectively. Crystal structure and conductivity of the samples were characterized by X-ray diffraction (XRD) and DC van der Pauw measurements, respectively. A limiting current oxygen sensor was fabricated with 8YSZ solid electrolyte and LSM dense diffusion barrier by a slurry spin coating method. The process parameters and sensing performances were investigated. Results: LSM is perovskite structure. The total conductivity of LSM is 104.95–162.18 S·cm−1 from 300 to 800 °C. The obtained optimum process parameters of slurry spin coating are: ethyl cellulose content of 3 wt%, coating cycle number of 7 and sintering temperature of 1400 °C. The sensor exhibits a good limiting current plateau that depends linearly on the oxygen concentration, and exponentially on the reciprocal temperature.

Effects of Ethyl Cellulose on Performance of Titania Photoanode for Dye-sensitized Solar Cells

Ethyl cellulose (EC) was added to a titania (TiO2) paste from 2 wt.% to 18 wt.% as a binder/dispersant, and its effects on the photovoltaic performance of dye-sensitized solar cells (DSSCs) were investigated. The TiO2 mesoporous film constructed on the photoanode exhibited a dense and network structure composed of well-interconnected TiO2 nanoparticles when using a proper amount of EC (10 wt.%). Excessive and deficient addition of EC resulted in aggregation of TiO2 nanoparticles and formation of pores, respectively, in the TiO2 film. The power conversion efficiency (PCE) of DSSC showed a strong dependence on the EC content and the highest PCE of 7.53% with the highest short-circuit current density (J SC) of 12.7 mA/cm2 was achieved when the content of EC was 10 wt.%. The incident photon-to-current conversion efficiency (IPCE) results indicated that the TiO2 mesoporous film fabricated using a proper EC addition was beneficial for electron generation (also confirmed by dye desorption experiments) and electron transport, and, therefore, improved the photovoltaic performance of DSSCs.

Structural Orientations of Cellulose Acetate Phthalate/Ethyl Cellulose Blends in Solution

Cellulose acetate phthalate/ethyl cellulose blends were investigated by means of attenuated total reflection Fourier transform infrared spectroscopy (ATR-FTIR), thermogravimetry/differential thermal analysis (TGA-DTGA), shear viscosity and oscillatory shear tests. The studies showed a higher thermal stability, induced by the occurrence of hydrogen bonding, more predominant in ethyl cellulose and blends with higher content of ethyl cellulose. The effect of solution concentrations in N,N-dimethylacetamide, blend compositions and shear rate on the rheological functions generated regions with properties typical for liquid crystalline solutions in the shear field. These studies are suggested to be useful in identification of liquid crystal properties, required in some electrotechnical applications.

Effects of polymer binder on rheological properties of silver pastes for screen printing front electrode films of solar cells

The purpose of the study is to characterize and improve the fundamental understanding of the effects of Ethyl Cellulose (EC) binder on the rheological properties of silver pastes for screen printing front electrode films of solar cells. Dispersions of silver particles (surface modified with oleic acid) in EC polymer solutions with and without thixotropic agent were prepared; and yield stress values were measured by setting shear stress to characterize the strength of interaction in pastes. Week flocculation network of silver particles is produced due to depletion of flocculation. EC polymer also has a significant interaction with thixotropic agent. Down-sweep flow curves of dispersions without thixotropic agent were measured and well fitted by Generalized Casson model. The model parameters p indicated that EC polymer with high molecular weight has a stronger shear-thinning ability. Steady-state flow, three interval thixotropy shear test (3ITT) and oscillatory measurements were conducted to study the effect of EC content on viscosity, structure rebuilding and viscoelastic properties of electrode pastes. Increasing EC polymer is not the best way to prevent the layer printed from laying down.

Rheological analysis of ceramic pastes with ethyl cellulose for screen-printing

Pastes of ceramic particles are used in many industrial applications such as in printed electronic products and solid oxide fuel cells. Ethyl cellulose (EC), a polymer component in the paste, is very useful to control the rheological properties of the pastes for screen printing. In this study, to prepare ceramic La0.6Sr0.4Ti0.3Fe0.7O3−δ (LSTF) pastes, EC was mixed with an organic solvent, ethylene glycol monobutyl ether acetate, and LSTF powder. The effects of EC and LSTF particle contents were investigated on the rheological properties of the pastes, using shear, stress, frequency-dependence, and a 3-step recovery tests. The recovery ratio of the pastes in the 3-step tests was found to depend strongly on their EC and LSTF particle contents, decreasing at higher contents due to the formation of a strong network. We also investigated the microstructure and surfaces of thick films fabricated through screen-printing, and confirmed that pastes with a low recovery ratio and high viscosity afford smooth surface profiles.

The relation between TiO2 nano-pastes rheology and dye sensitized solar cell photoanode efficiency

TiO2 nanoparticle pastes for screen printed semiconductive photoanodes of dye sensitized solar cells were prepared with different content (from 0 to 9wt%) of ethyl cellulose and evaluated by rheology measurements. The effect of ethyl cellulose content in the paste is crucial for printed and sintered TiO2 photoanode properties as thickness, roughness and amount of adsorbed dye, measured by profilometry, atomic force microscopy, IR and UV‐Vis spectroscopy. Moreover, the expressive correlation among paste rheology, layer properties and the final dye sensitized solar cell efficiency depending on the initial ethyl cellulose content was found, including correlations of the properties local maxima positions. The highest efficiency was achieved for the TiO2 paste with 6.5wt% of ethyl cellulose, where initial paste viscosity and thixotropy, printed layer thickness, roughness and amount of adsorbed dye achieved the local maxima (~40Pa.s,4.5µm, 24nm, 1.92×10−8mol/cm2, respectively) that indicates the optimal structure of the oxide photoanode layer. The results confirm the importance of controlled ethyl cellulose concentration and rheological properties of applied pastes for higher DSSC efficiency achievement.

Fabrication of LSGM thin films on porous anode supports by slurry spin coating for IT-SOFC

La0.9Sr0.1Ga0.8Mg0.2O3−δ (LSGM) and La0.7Sr0.3Cr0.5Mn0.5O3−δ (LSCM) powders were synthesized by glycine-nitrate process, and LSGM electrolyte thin film was successfully fabricated on porous anode substrate of LSCM by slurry spin coating technology. Some technical parameters for the preparation of LSGM thin films were systematically investigated, including ink composition, sintering temperature, and spin coating times. The electrolyte films with the best compactness and somewhat rough are obtained when the operating parameters are fixed as follows: the content of ethyl cellulose as binder is 5 wt%, the content of terpineol as modifier is 5 wt%, the optimum coating cycle number is 9 times, and the best post-deposition sintering temperature is 1,400 °C for 4 h.

Optimization of TiO2photoanode films for highly efficient quantum dot-sensitized solar cells

As a fundamental part of quantum dot-sensitized solar cells, the composition and configuration of the TiO2 photoanode film plays an important role in photovoltaic performance. In this work, the preparation and optimization of films have been systematically studied, including the TiCl4 treatment technique, transparent layer and light-scattering layer thickness and composition. Experimental results show that the sole TiCl4 treatment on fluorine doped SnO2 (FTO) glass is sufficient for achieving a high efficiency in the resultant cell devices when compared with the simultaneous treatment on both FTO glass and TiO2 mesoporous films. The thickness and porosity of the transparent layer have been optimized by tuning the number of transparent layers and the ethyl cellulose contents in the paste. Moreover, the influence of the light-scattering layer pastes with different contents of the large-sized TiO2 particles on the performance of the cells has also been explored. The CdSe-sensitized solar cells based on the optimized TiO2 film photoanode exhibits a power conversion efficiency of 5.53% under 1 full sun illumination, which is among the best efficiencies for plain CdSe QD-based solar cells.