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Showing 1 to 20 of 27 for “"Solubility parameters"”.
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Correlation of Polymer Performance and Hansen Solubility Parameters
… of this research was to investigate formulation parameters and how they affect grout performance. It was learned that particle size and oil absorption (OA) value are important filler properties that affect performance as much as adequate packing density and optimal pigment volume concentration …
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The Use of Solubility Parameters to Select Membrane Materials for Pervaporation of Organic Mixtures
… The paint processing industry uses Hansen solubility parameters (HSP) to indicate polymer solubility. The potential of this method to predict solvent-polymer affinity was investigated for screening potential membrane materials for the pervaporation of a model solution containing linalool …
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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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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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Using Covalent and Non-Covalent Chemistry to Control Properties of Single -Walled Carbon Nanotubes
… with sodium cholate surfactant. Solution-phase solubility without surfactants can be achieved using high levels of covalent functionalization with aryl hydroxyl or aryl carboxylic acid moieties. Polymer theory based models for the Hildebrand and Hansen solubility parameters confirm the effect of …
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The effect of hydrocarbon exposure and temperature on the behaviour of elastomeric seals
… aromatic rings) as well as increasing all Hansen solubility parameters increased swelling. Of the Hansen solubility parameters, the greatest correlation was found with the hydrogen-bonding (electron exchange) parameter. Nonetheless the dispersion parameter which is strongly affected by the number …
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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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Simultaneous Degradation of Toxic and Volatile Substrates by Two Phase Partitioning Bioreactor Systems: Performance Characterization and Rational Polymer Selection
… using three different methods, Hildebrand solubility parameters, Hansen Solubility Parameters (HSP) and activity coefficients at infinite dilution. It was found that the HSP method gave the best trends and its predictions had better agreement with the experimental results. Consequent …
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I. Solubility and blend studies of nitrocellulose II. Relaxation properties of thin film coatings: the role of surface topography
… first part of this two part thesis, interaction parameters of nitrocellulose with various solvent systems were investigated by Inverse Gas Chromatography. From these data, the solubility parameters of nitrocellulose were determined at a series of nitration levels which were used to guide the …
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Study of controlled release of active pharmaceutical ingredients from functionalized nanoclays and polymer matrices
… and as a result it showed increased apparent solubility in the simulated body fluids. The second study dealt with API-polymer miscible or immiscible systems prepared by different mixing methods. The selected APIs have low solubility at the low pH of the aqueous medium and different solubility …
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TEM/EDXS studies of phase separation in block and graft copolymers
The relationships between molecular parameters and microdomain formation of a variety of block- and graft-copolymers were studied by Transmission Electron Microscopy (TEM). Molecular variables included chemical composition: dimethyl-, fluoropropyl and diphenyl-siloxane , sulfone styrene, …
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The use of ion pairs to increase the percutaneous delivery of diclofenac
… skin in vitro permeation testing (IVPT). Next, solubility challenges were addressed by assessing diclofenac sodium (DNa) solubility in various pharmaceutical solvents. Transcutol® (TC), propylene glycol (PG), and dipropylene glycol (DiPG) were selected for high DNa solubility and water …
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Ionic liquids as additives for biodegradable polyactic acid
… T_g, characterization, as well as from solubility parameters calculations. The effects of the IL containing a decanoate anion were more pronounced on lubrication and degradation as evidenced by reduced melt viscosities and accelerated thermal/hydrolytic degradation; this IL could also …
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Viscosity and Stability of Visbroken Fractionated Oils
… (molecular weight, density, viscosity, and solubility) of each fraction were measured. Previously developed correlations for molecular weight, density model parameters, viscosity model parameters, and solubility parameters were updated. The density of the oils was determined with a …
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Solubility Enhancement and Precipitation Inhibition of Poorly Water Soluble Compounds Utilizing Hot Melt Extrusion Technology
… was utilized to determine the miscibility and solubility of the model compounds within Soluplus® , of which felodipine demonstrated higher solubility when compared to ketoconazole (14% vs 4.3% w/w) at room temperature (298K). Moreover, the solubility parameters of FEL, KTZ and SOL were …
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The effect of different chemical classes on the swelling of NBR O-rings in blends with synthetic paraffinic kerosene
… measurements, although with lower repeatability. Solubility parameters and molar volume were shown to be key determinants of seal swell. It was demonstrated that the extent of swell was not significantly different between n- and iso- isomers of octane and dodecane. What was different was that …
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Design and Synthesis of Complex and Fluorescent Labeled Cellulose-Based Derivatives for Orally Administered Drug Delivery Systems
… by the similarity of the polymer and drug solubility parameters. I was further able to confirm via polarized light microscopy that advantageous nanodroplet formation occurs during the drug-release process.
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Hydroxypropylmethylcellulose: A New Matrix for Solid-Surface Room-Temperature Phosphorimetry
This thesis reports an investigation of hydroxypropylmethylcellulose (HPMC) as a new solid-surface room-temperature phosphorescence (SSRTP) sample matrix. The high background phosphorescence originating from filter paper substrates can interfere with the detection and quantitation of trace-level …
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Fabrication and characterization of cellulose nanocrystal enhanced sustainable polymer nanocomposites through surface chemistry and processing
… them in organic solvents with different Hansen’s solubility parameters. The dispersibility of grafted CNCs in organic solvents was improved by using never-dried CNCs as source materials and keeping CNCs wet in their washing solvents after grafting, thus increasing the solvency range to disperse …
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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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