Sticky, products

Sufficient alcohol is used to dissolve the benzaldehyde rapidly, as well as to retain the benzalacetone in solution until it has had time to react with the second molecule of aldehyde. Lower concentrations of base slow up the formation of the dibenzalacetone and thus favor side reactions which tend to yield a sticky product. Higher concentrations of base give added difficulty in washing. These concentrations were suggested by, and are approximately the same as, those used in the preparation of benzalacetophenone described in Org. Syn. 7, r. 

The benzaldehyde was U.S.P. quality which had been washed with sodium carbonate solution and distilled. Commercial C.P. acetone was used. The theoretical quantities are used, since an excess of benzaldehyde results in a sticky product, and an excess of acetone favors the production of benzalacetone. The mixture is prepared before addition in order to insure additions of equivalent quantities. 

The addition of surfactants to milk fat may also improve butter texture (Gupta and deMan, 1985). Butter spreadability was improved in some cases, depending on the nature of the surfactant (Kapsalis et al., 1963). Some surfactants resulted in a brittle and sticky product. Also, the effect of the surfactants was found to be temporary. Setting was delayed, but ultimately there was no effect of the surfactants on the SFC of butter (Kapsalis et al., 1963). For this reason, surfactants have little practical significance for butter rheology (Hayakawa et al., 1986). 

Pulsed sieve-plate columns have shown good efficiencies for frequencies between 60 and 150 strokes/min and amplitudes under 1 cm. In general, a plate spacing of 10 cm is considered most favorable. However, these columns operate well in only a limited load range and are also susceptible to fouling, particularly with sticky products. To some extent, the reduction in efficiency at underload can be compensated by changing the pulsation characteristics the load can also be artificially increased by recycling the raffinate. 

Starch has two classes of use in confectionery gelling and non-gelling. Where the starch is non-gelling it is usually being used as a substitute for a gum. Native starch is little used in confectionery - probably the only use of native starch is where it is used to dust a sticky product, e.g. Turkish delight. 

The only way to get enough quinine was to develop a synthetic version of the drug. During a vacation from college, Perkin was at home experimenting with ways of making synthetic quinine. One of his experiments resulted in a product that was a thick, sticky, black substance. He immediately realized that this attempt to synthesize quinine did not work. Curious about the substance, Perkin washed his reaction vessel with water. But the sticky product would not wash away. Perkin next decided to try cleaning the vessel with an alcohol. What he saw next was an unexpected discovery. 

Va (17). In a 250-mL, three-necked flask, 4.8 g (0.01 mol) of 2,4-didodecanoxy-6-chloro-s-triazine and 3.0 g of 2,6-diphenylhydroqui-none(III) were placed in 150 mL of dry acetone. To this solution 0.4 g of NaOH dissolved in 7 mL of water was added dropwise under N2. After the addition was complete, the reaction mixture was kept at reflux for 45 min. The orange-red color disappeared gradually. The reaction product was poured in ice water, extracted with diethylether, washed, dried over MgS04, and ether was removed in vacuo. The slightly colored, sticky product solidified at 15°C. Yield, 7 g 98%. 

If the chain extension is faster than the crosslinking activity, the system builds to a gum with very low crosslink density and a gummy, sticky product results. If the crosslinking is faster than the chain extension, then a tough, high modulus, low elongation sealant results. 

Prolonged exposure to light, or failure to control exothermic reactions in prior steps, results in a sticky product which smells of pyridine. No method for purifying partly decomposed MoOPH has been found, and "sticky" product should not be used for enolate hydroxyl ation. Suspect material can be decomposed by stirring with aqueous sodium sulfite (Na2S03) solution. 

The controlled formation of defined particles (particle size, particle size distribution, composition, etc.) is important to several kinds of production lines, including those in the pharmaceutical, pigment and catalyst industries. Milling and crystallization are the most commonly used microionization processes here, but these methods suffer from some limitations (a) it is difficult to control particle size and particle size distribution (b) recrystallization leads to solvent-contaminated compounds and (c) milling is not suitable for the treatment of heat- or even of shock-sensitive substances, or for highly viscous or sticky products. 

The rotacurrent dryer can handle particulate and non-sticky products such as aluminum silicate, copper powder, pyrite ore, charcoal, granulated rubber, chopped straw, detergents, and the like [75]. Performance data on the rotacurrent dryer are given in Table 21.21. 

The chamber in Figure 48.1c has cyclone-like dimensions, i.e., a short cylindrical side in relation to an extended cone section, and has a mixed flow concept with air entering and leaving the top of the chamber. This chamber is ideal for heat-sensitive, sticky products and has enabled many products to be spray dried successfully for the first time. Although it has... 

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