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Showing 1 to 20 of 26 for “"Solubility parameter"”.
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Solubility Enhancement via Melt Extrusion: Drug-polymer Solubility, Physicochemical Characterization and Quality by Design
… is a very widely applied technique for solubility enhancement of water insoluble drugs. In order to form stable solid dispersions it is important to select appropriate excipients that will maintain the drug in its amorphous form for an extended period of time. Selection of appropriate …
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Computational prediction of enhanced solubility of poorly aqueous soluble drugs prepared by hot melt method
<p>Solubility is the concentration of a solute in a saturated solution at a given temperature and pressure. Solubility of a drug in aqueous media is a pre-requisite to achieve desired concentration of a drug in the systemic circulation. Low aqueous solubility is a major problem encountered with …
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Characterization and Asphaltene Precipitation Modeling of Native and Reacted Crude Oils
… requires mole fractions, molar volumes, and solubility parameters for the pseudo-components representing the crude oil mixture. The pseudo-components used in the RSM, based on a solubility fractionation method (modified ASTM D4124 technique), are namely saturates, aromatics, resins, and …
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Volumetric Properties and Viscosity of Fluid Mixtures at High Pressures: Lubricants and Ionic Liquids
… In addition, a method of estimating Hildebrand solubility parameter was employed, allowing for solubility parameter to be put in terms of pressure, temperature, and composition. The effect of cosolvent addition on the thermodynamic properties was changed by the length of the alkyl group on the …
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Study of controlled release of dapsone from modified montmorillonite and polymer matrices
… was prepared by melt mixing. In agreement with solubility parameter differences, Dapsone exists in an amorphous state in the polymer matrix. The API-modified clay was dispersed in the polymer to form a ternary system, in which the API showed a more controlled release profile due to the presence …
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Characterization of polyphenoxy-ethylphenoxyphosphazene-bulk sealant applications
… sealant application. Investigation of the solubility parameter through solvent ingression experiments determined the solvent resistive abilities of the material. Thermogravimetric analysis set an upper temperature limit of application by determining the thermal stability of the polymer. The …
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The blending of hydroxypropyl lignin with poly(methylmethacrylate) and poly(vinyl alcohol)
… and evaluated in terms of HPL content and PVA's solubility parameter. Blends of HPL and PVA formed homogeneous materials over a much broader range of solubility parameters than would be predicted from the theory of matching solubility parameters. It was concluded that hydrogen bonding between …
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Application of Hansen Solubility Parameters and Thermomechanical Techniques to the Prediction of Miscibility of Amorphous Solid Dispersion. Investigating the role of cohesive energy and free volume to predict phase separation kinetics in hot-melt extruded amorphous solid dispersion using dynamic mechanical analyser, shear rheometer and solubility parameters data
… is increasingly employed to improve the solubility of poorly water-soluble drugs. The technique relies on the enhanced solubility of the amorphous form of the drug compared to its crystalline counterpart. These systems however are thermodynamically unstable. This means that the drug …
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Polymeric capsules for self-healing anticorrosion coatings
… unreasonable. Therefore, exploitation of the solubility parameter approach was found to be more useful. The latter allows consideration of the properties of each single component instead of the pair of components. In such a manner, the Hansen Solubility Parameter (HSP) approach was used for …
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Optimizing the structure and plasticization resistance of asymmetric polyimide hollow fiber membranes for CO2 removal from natural gas
… have evaluated many of the critical fabrication parameters and optimized those parameters as regard to the membrane physical and separation properties. Asymmetric hollow fibers with CO2/CH4 separation factors up to 67 were successfully fabricated under the optimum fabrication conditions. Our …
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Investigating Crystallization Tendency, Miscibility and Molecular interactions of drug-polymer systems for the development of amorphous solid dispersions
… along with theoretical calculations such as solubility parameter were performed to study drug polymer miscibility. Molecular interactions were predicted by using Tg deviations and molecular modeling. Physical states of drug in the SDs were characterized by X-ray diffraction (XRD) and MDSC. IR …
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Removal of polymer coating with supercritical carbon dioxide
… developed is built upon the three-component solubility parameter (HSP) concept, which is widely used in the coatings industry to aid in the selection of solvents. Temperature and pressure dependent HSP values have been develop for supercritical CO2, using a methodology extendable to other …
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Predicting aqueous solubility of pharmaceutical agents by solid dispersion prepared by solvent evaporation method
<p>Solubility of active pharmaceutical agents is a crucial process that determines drug absorption and ultimately its bioavailability. Many of the new therapeutically beneficial compounds discovered are lipophilic requiring various solubility enhancement strategies to improve their solubility. …
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Development and Evaluation of Ternary Amorphous Solid Dispersion of Poorly Water-soluble Compounds
… anticancer activity. However, their poor aqueous solubility limits their oral application. The purpose of this study is to design, characterized, and evaluate a soluble and stable TASD containing CUR and RES with a hydrophilic polymer. Methods: Choosing an optimum polymer can be considered as one …
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Development of Sustainable Thermoplastic Elastomers
… composition of SAS) was utilized as a convenient parameter for tuning the physical properties of SAS, including the melting temperature and viscosity of the midblock polyacrylate, melt viscosity of SAS above the ODT, and tensile properties. The thermodynamic interactions between the components of …
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Study of the dilute solution properties of various homo- and block co-polymers by variable temperature size exclusion chromatography
… selective solvent, its extent depending on the solubility parameter difference between the components, molecular weight, composition and solvent power. In the third part, poly(methyl methacrylate) samples with varying tacticities were studied as to the effect of stereochemical configuration on …
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Dépolymérisation de la cellulose dans des mélanges fluides binaires et ternaires riches en CO2 à hautes pressions
… such as wood. Based on hydrogen bonding and solubility parameter concepts, different fluids were selected: pure carbon dioxide and water, the binaries: CO[subscript 2] - water; CO[subscript 2] - methanol and CO[subscript 2] - acetone and the ternaries: CO[subscript 2] - water - methanol and …
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Study of gold-based alloy phase diagrams
… AuIn, Auln2' AuGa, AuGa2' AuZn and AuCd. The solubility of Ge in the AuX compounds was not determined directly. However, it was 1.3 at.% Ge for Zn and Cd containing alloys and less than 1.0 at. % Ge for In and Ga containing alloys at the eutectic temperatures, which is in accordance with the …
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Development and manufacture of novel amorphous Itraconazole drug products using quality by design principles
The aim of this thesis was to improve the poor solubility of Itraconazole (ITZ) through novel approaches to product development using continuous manufacture with novel in-line process analytical technology (PAT) to monitor quality. The solubility parameter () of ITZ and polymers, Kollidon® VA64 …
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Design and development of drug delivery systems for immediate and sustained release utilizing hot melt extrusion
… of API can have as much as 10-1600 fold higher solubility than their crystalline forms. HME technology is extensively been used to convert crystalline form to amorphous form of drug with increased solubility with polymeric matrices as carriers. Efavirenz (EFZ) and Carbamazepine (CBZ) are …
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