Resin solvent evaporation from

Predicted Compositions during Mixed Solvent Evaporation from Resin Solutions Using the Analytical Solutions of Groups Method... 

Solvents are used to carry dissolved or suspended resin and evaporate from the coating after application. Additives in small amounts are used as mildew inhibitors (cuprous compounds), surface-drying additives (manganese and cobalt naphthanates), and barrier-forming additives to protect the resin from heat and UV degradation. Fillers (talc and mica) decrease the permeability of oxygen and water in the coating. 

Solvent release n. The ability of a resin to influence the rate at which solvent evaporates from a coating. 

Spray drier n. A cylindrical or conical-bot-tomed chamber through which hot air rises and into which a resin emulsion is sprayed in small droplets. The solvent evaporates from the droplets as they fall and the dried-resin powder is removed from the chamber bottom by scraping or air blasting. Spray drying has been employed for emulsion-polymerized vinyl resin, and for amino and phenolic resins. 

Oleoresins are the flavour extracts obtained by the solvent extraction of the ground spices or vegetables and solvent evaporation from the misceUa. They are mixtures of essential oils, resins... 

An all aromatic polyetherimide is made by Du Pont from reaction of pyromelUtic dianhydride and 4,4 -oxydianiline and is sold as Kapton. It possesses excellent thermal stabiUty, mechanical characteristics, and electrical properties, as indicated in Table 3. The high heat-deflection temperature of the resin limits its processibiUty. Kapton is available as general-purpose film and used in appHcations such as washers and gaskets. Often the resin is not used directly rather, the more tractable polyamide acid intermediate is appHed in solution to a surface and then is thermally imidi2ed as the solvent evaporates. 

The solvent was evaporated from the combined benzene extracts to give 33.4 g of a clear light brown resin. Crystallization from an alcohol-water mixture gave 19.5 g of 1-methyl-4-(5-hydroxy-5-dibenzo[a,e] cycloheptatrienyO-piperidine, MP 156° to 157°C. Two recrystallizations from alcohol-water mixtures followed by two recrystallizations from benzene-hexane mixtures gave analytically pure product, MP 166.7° to 167.7°C. 

Analytical methods for detecting phenol in environmental samples are summarized in Table 6-2. The accuracy and sensitivity of phenol determination in environmental samples depends on sample preconcentration and pretreatment and the analytical method employed. The recovery of phenol from air and water by the various preconcentration methods is usually low for samples containing low levels of phenol. The two preconcentration methods commonly used for phenols in water are adsorption on XAD resin and adsorption on carbon. Both can give low recoveries, as shown by Van Rossum and Webb (1978). Solvent extraction at acidic pH with subsequent solvent concentration also gives unsatisfactory recovery for phenol. Even during carefully controlled conditions, phenol losses of up to 60% may occur during solvent evaporation (Handson and Hanrahan 1983). The in situ acetylation with subsequent solvent extraction as developed by Sithole et al. (1986) is probably one of the most promising methods. 

A very convenient method has been devised [40] for the conversion of thiols to ethyldithio derivatives as a routine procedure for protection of thiol-substituted organic acids. It uses a DMAP-catalysed exchange of the ethylthio group between a thiol and ethyl 2-pyridyl disulfide, prepared from the commercially available 2,2 -dithiobispyridine. Filtration through a macroporous sulfonic acidic resin and evaporation of the solvent yielded the disulfide directly. 

K[(CH3)3Pt]Pt(CN)4, is isolated from an aqueous solution of the nitrate by adding potassium platinocyanide. A slimy yellow precipitate is formed, insoluble in water and the usual organic solvents except acetone and alcohol. On evaporation from one of these solvents an amorphous resinous greenish-yellow compound is produced which, from determination of the platinum, appears to correspond to K2Pt(CN)4[(CH3)3Pt]2Pt(CN)4. 

Water-Based Inks. Approximately 50% of all flexographic inks use water as their primary solvent and diluent. They contain vehicles based on either acrylic emulsions, or hydrosols or an alkali-soluble rosin ester having a high acid number such as partially esterified fiimurated rosin and shellac. Carboxylated acrylic polymers, usually containing some styrene, have largely replaced natural resins because they provide better abrasion and water resistance. Ammonia or other volatile amines are used to solubilize these carboxylated resins and form resin salts. The volatile alkali evaporates from the ink film, rendering the printed matter water resistant. 

Amino-6-chloro-9-[2-(2,2-dimethyl-l,3-dioxan-5-yl)-ethyl]purine (0.59 g, 1.9 mmol) in hydrochloric acid (1.0 M, 4 ml) was stirred at 60°C for 24 hours. The solution was diluted with water and neutralised with Amberlite IR 45. The mixture was filtered, the resin washed with water and the solvent evaporated under reduced pressure. The residue was recrystallised from water to afford 9-(4-hydroxy-3-hydroxymethylbut-l-yl)guanine (238 mg, 49%), melting point 275°-277°C. 

Polar solvents are required with polar resins nonpolar solvents with nonpolar resins. When solvents are used in the adhesive formulation, they must be completely evaporated from the bond line prior to cure, or otherwise bubbles could form in the bond line, causing a weak joint. The substrate must also be tested so that the solvents that are used in the adhesive formulation do not attack or degrade it. 

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