Hydrocarbon blends

Propellants. The propellant, said to be the heart of an aerosol system, maintains a suitable pressure within the container and expels the product once the valve is opened. Propellants may be either a Hquefied halocarbon, hydrocarbon, or halocarbon—hydrocarbon blend, or a compressed gas such as carbon dioxide (qv), nitrogen (qv), or nitrous oxide. 

A site in northern New Jersey was to be remediated by Sybron using the ABR Hydrocarbon blend in 1995/1996. This application was an in situ soil remediation described in Case Study 1 (see D14650J, p. 21). The projected cost for the soil clean-up was approximately 11 per ton or 14.50/yd for the 35 -acre treatment area. 

The current RP-1 hydrocarbon fuel used in high thrust boosters is an example of a special kind of tailoring. This hydrocarbon blend or distillation cut was selected to meet a series of special property and combustion requirements for liquid oxygen-oxidized high thrust systems. 

Another biosynthetic issue is the origin of complex hydrocarbon blends, such as the 11 different tetraenes of Ca. hemipterus (Figure 19.3). While there could be separate biosynthetic systems for each of the Ca. hemipterus tetraenes, a more parsimonious explanation, which fits the data, is that a single biosynthetic system exists with imperfect selectivity for acyl units (Bartelt et al., 1992b). If the most abundant tetraene, 5, represents the normal product, then tetraenes 6,7,14, and 18 represent instances of one acyl substitution (or biosynthetic mistake ). There are six possible ways in which two of these substitutions could exist in one compound, and these are represented by 8,15,16,19,20, and 21. Occurrence of two substitutions would be rarer than just one, and the observed abundances reflected this expectation. Tetraenes with three or four substitutions would be even rarer, and these were not detected. Substitutions were never observed for the second acyl unit, which was unfailingly propionate. Related arguments can be made for the patterns of hydrocarbons in Ca. freemani and Ca. davidsoni (Bartelt et al., 1990b Bartelt and Weisleder, 1996). 

An early approach to predicting TCC flash points for hydrocarbon mixtures used this concept by estimating flash point as the temperature at which mixture vapor pressure reached about 10 mm Hg (3). Other workers (4) have found both the product of vapor pressure at the flash point and molecular weight to be constant for a number of hydrocarbon fractions. The TCC flash point for hydrocarbon blends was predicted as the temperature at which... 

Alcohol-hydrocarbon blends are often modified with ethyl acetate. Adding ethyl acetate to alcohol-heptane blends (with the exception of... 

A comparison of potential cresol replacements is given in Table 2 [143]. None of the solvents shown there is a full equivalent to cresol. Because of the reduced solvency power for poly(ester-imide)s the varnishes contain less hydrocarbons blended in and the heat of combustion is lower than that of a cresylic varnish, undesired for the existing installed enameling machines. 

Figure 2. Comparison of hydrophobic silica antifoam properties. The blank is an untreated styrene—butadiene latex. Compound A is an aqueous blend. Compound Bis a hydrocarbon blend.

Table 6. Composition of hydrocarbon component of TOT complex crystals grown from hydrocarbon blends...

C hydrocarbons blended with additives and used as a fuel in spark-... 

Chem. Descrip. Modified glycol/hydrocarbon blend Uses Defoamer for metalworking fluids, printing inks, latex paints, adhesives/caulks/sealants, wood stains, floor wax cleaning compds. Regulatory FDA compliance Properties Liq. sp.gr. 0.85-0.88 100% act. 

Chem. Descrip. Fatty acid/hydrocarbon blend Uses Defoamer for metalworking fluids, printing inks, latex paints, adhesives/caulks/sealants, wood stains, paper coatings, water-reducible systems, aq. resin and latex coatings, textile preps. food pkg. adhesives component of paper/paperboard in contact with aq./fatty foods Features Silicone-free high efficiency low cost Regulatory FDA 21CFR 175.105,175.300,176.170 Properties Off-wh. opaque low-vise, liq. sp.gr. 0.86-0.89 nonionic 100% act. 

The viscosity dependence on polymer molecular weight is demonstrated in Figure 2.21 whereas Figure 2.22 shows the effect of polymer/solvent interaction. In the latter, the viscosity of solutions of a thermoplastic rubber at constant concentration and temperature is given in various hydrocarbon(blend)s. In this example hydrogen bonding or polar effects play no or only a very limited role. It is clear that in this case the solution viscosity is very much influenced by the Hildebrand solubility parameter of the solvent in relation to that of the polymer (8.2-9.1). 

Hair spray consists of a resin dissolved in a solvent (usually ethanol but can be isopropanol) and a propulsion system to place the product onto the hair. The propulsion system is mainly the condensed gas aerosol (hydrocarbon blends or dimethyl ether) but pump and compressed gas systems are available. 

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