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Waxes dissolution

Downhole wax inhibitor injection will not he required since the stabilized flowing temperature within the well tubing and at the wellhead will be some 55°C which is wpll above the cloud point and wax dissolution... [Pg.15]

Solvent plastics, gasoline, varnishes, lacquers, stains, inks, fats, oils, and waxes dissolution in the substrate azo, triphenylmethane, anthraquinone, and phthalocyanine... [Pg.4]

RPLC-PDA is frequently used for quality control, such as the determination of free Irganox 1098 in PA4.6 (at 278 nm after dissolution/precipitation), of free Irganox 1010/1076 in PP (at 278 nm after extraction with MTBE, thus avoiding dissolution of polymer waxes), of Luperco 802 in PP (at 218 nm, after extraction with HCC13), and of Tinuvin 122 in HDPE (at 225 nm as diol). The advantages of the use of HSLC over conventional LC in QC of plastics and additives have been demonstrated, e.g. for AOs in PE, mixed phthalate esters and residual terephthalic acid in PET and partially cured epoxy resins [557],... [Pg.252]

The comparison of the 2D plot of a graft copolymer with the 2D plot of the precursor PEO shows clearly that the graft copolymer sample does not contain any free PEO. This result was also confirmed by MALDI-TOF mass spectrometry. Next to the requirement of being PEO free, the PEO-g-PVA copolymers showed a good combination of film-forming properties, a fast dissolution, and a low solution viscosity in water. The phase separated morphology, as demonstrated by TEM, DSC, DMTA, and WAXS experiments, provided the PEO-g-PVA copolymers with relatively constant mechanical properties. [Pg.403]

Sticker, in glass dissolution, 22 456 Sticky dental wax, 3 299-300 specification, 8 300t... [Pg.887]

For acid-labile drugs, a coating of wax or of a cellulose acetate polymer is used to prevent disintegration of solid dosage forms in the stomach. Accordingly, disintegration and dissolution will take place in the duodenum at normal speed (A, track 1) and drug liberation per se is not retarded. [Pg.10]

After dissolution came Conjunction, wherein the separated elements were combined. Then followed Putrefaction, necessary for the germination of the seed which had been produced by calcination, dissolution, and conjunction. Putrefaction was followed by Congelation and Citation. The passage through the next gate, called Sublimation, caused the body to become spiritual, and the spiritual to be made corporal. Fermentation followed, whereby the substance became soft and flowed like wax. Finally, by Exaltation, the Stone was perfected. [Pg.32]

Dissolution- and diffusion-based technologies can be utilized to obtain various novel profiles of drug release. For example, a repeat-action tablet can be created wherein the tablet provides two immediate release doses, with a time interval. This technology is used in Proventil Repetabs to provide two doses of albuterol (2 mg) separated by six hours. Acacia and carnauba wax are the polymers used in this specific case to provide two immediate release doses over a defined period. [Pg.342]

The crude was circulated through the test tube with a wall temperature of 5°f and a crude temperature of 65°C. After two hours the test tube temperature was continuously Increased at a rate of 2°C/hr. A plot of pressure versus time and wall temperature (Fig. 7) shows that wax deposition occurs at wall temperatures below 25°C. Above 25°C the pressure decreased Indicating dissolution of wax, and at approximately 35°C, the pressure equals the initial pressure indicating that all the deposited wax had been dissolved. [Pg.14]

A recent novel approach uses the PLGA polymer as a sustained-release coating on budesonide dry powders. Talton et al. showed that these coated particles conferred a statistically significant increase in pulmonary targeting in rats compared with uncoated budesonide powders [101], Another approach uses a wax coating to control particle dissolution. Pillai et al. produced paraffin wax-coated fluores-... [Pg.78]

R. S. Pillai, D. B. Yeates, I. F. Miller, and A. J. Hickey, Controlled dissolution from wax-coated aerosol particles in canine lungs, 7. Appl. Physiol. 87 1878 (1998). [Pg.89]

If a solvent and solute are nonpolar, the interaction force between them is of the van der Waals type 1 kJ/mole) where as the distance between them becomes closer, the interaction energy increases rapidly to the twelfth power of the distance. The induced dipole-induced dipole interaction mainly accounts for the dissolution of nonpolar solutes in nonpolar solvents such as paraffin in petroleum benzin or wax in CC14. The net heat of solution becomes zero or very small for nonpolar systems when the solute and solvent molecules are of similar size and structure. In this case, the interaction energies of solute-solute, solvent-solvent, and solute-solvent are of the same magnitudes. Materials that can be soluble with zero heat of solution are often called ideal solutions. [Pg.138]

Adeyeye, C. M., and Price, J. C. (1997), Chemical dissolution stability and microscopic evaluation of suspensions of ibuprofen and sustained release ibuprofen-wax microspheres, /. Microencapsul., 14(3), 357-377. [Pg.344]

In the area of the leaf surface in contact with the . graminis film, the cuticle loses its original integrity as evidenced by the apparent dissolution of surface wax crystals. Within 60 min the film disappears and the surface of the conidium again assumes the morphology of the unstimulated state. [Pg.226]

Important solvent properties are volatility, viscosity, surface tension, and lipid solubility. The first three determine the area over which a given volume of solvent spreads the larger the area of contact between insecticide and outer cuticle layers, the larger its total penetration rate will be. Acetone does not spread very far from the site of application, because it is so volatile. Lipid solubility affects the dissolution of the wax components of the epicuticle. By disrupting this layer, e.g., depositing a drop of acetone, the insecticide could bypass the epicuticular barrier. All these effects together may explain why an optimal balance of solvent properties is necessary to obtain maximal penetration rates (Welling and Patterson, 1985). [Pg.109]

Sato, H. Miyagawa, Y. Okabe, T. Dissolution mechanism of diclofenac sodium from wax matrix granules. J. Pharm. Sci. 1997, 86, 929-934. [Pg.2019]

Small aerosol particles, 1-5 pm in diameter, have been condensation coated from a vapor of a fatty acid or paraffin wax. These particles have been shown to exhibit reduced dissolution rates in vitro, corresponding to reduced absorption rates following deposition in the lungs of Beagle dogs. [Pg.2330]


See other pages where Waxes dissolution is mentioned: [Pg.14]    [Pg.2018]    [Pg.14]    [Pg.2018]    [Pg.463]    [Pg.134]    [Pg.78]    [Pg.53]    [Pg.65]    [Pg.148]    [Pg.694]    [Pg.178]    [Pg.453]    [Pg.280]    [Pg.242]    [Pg.363]    [Pg.14]    [Pg.16]    [Pg.21]    [Pg.512]    [Pg.140]    [Pg.79]    [Pg.463]    [Pg.426]    [Pg.374]    [Pg.110]    [Pg.3065]    [Pg.766]    [Pg.768]    [Pg.975]    [Pg.992]    [Pg.1290]    [Pg.2330]   
See also in sourсe #XX -- [ Pg.148 ]




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