Volatiles, evaporation

Since methylated II is highly volatile, evaporation of the solvent to dryness should be avoided. 

KEY TERMS vapor pressure volatility evaporation vaporization endothermic... 

The FSD is a flash evaporator, whereby the preheated polymer solution/melt falls within the vessel primarily by gravity, while the volatiles evaporate during falling. This method is normally used with process streams that are not exceptionally temperature-sensitive and where the concentration of volatiles is relatively high. 

This is an example of a loss through volatilization (evaporation) under temperature conditions at which water would volatilize, hence the word drying. The loss can occur by elevating the temperature of the sample to just above the boiling point of water (although a different temperature may be specified) or through desiccation. This is not necessarily limited to water, however, as any sample component that volatilizes in the case of elevated temperature would be included in the weight loss. Thus it is called loss... 

Volatiles evaporate, and signals become weaker over time. In mixtures, evaporation of the more-volatile compounds can change the quality of the odor and the range over which it can be detected. This means that decaying and... 

The characteristics of the three most common thermoset resin systems used in pultrusion are compiled in Table 11.2 [3]. It is noteworthy that unreinforced polyesters and vinylesters shrink 7-9% upon crosslinking, whereas epoxies shrink much less and tend to adhere to the die. These epoxy characteristics translate into processing difficulties, reduced processing speed, and inferior component surface finish. It is normal practice to use resin additives to improve processability, mechanical properties, electrical properties, shrinkage, environmental resistance, temperature tolerance, fire tolerance, color, cost, and volatile evaporation. It is normally the resin, or rather its reactivity, that determines the pulling speed. Typical pulling speeds for polyesters tend to be on the order of 10-20 mm/s, whereas speeds may exceed lOOmm/s under certain circumstances. Apart from the resins characterized in Table 11.2, several other thermosets, such as phenolics, acrylics, and polyurethanes, have been tried, as have several thermoplastics (as will be discussed in Sec. 11.2.6). 

Volatilization evaporation t,/2 = 51 min from dilute aqueous solution (Dilling 1975)... 

Volatilization/Evaporation estimated evaporation rate from liquid surfaces at 100°C to be 0.009 mg/cm2h (Hutzinger et al. 1974) ... 

Fig. 59. Graph of relative volatility (evaporation) rates vs reciprocal temperature for Ba(dfhd)2, Ba(ofhd)2, Ba(fod)2, Ba(hfac)2, and Ba(ppm)2. (Redrawn from Ref. 213.)...

Volatile Evaporating rapidly at normal temperatures and pressures,... 

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