Acids aliphatic unsaturated

Besides steroids, axillary odor also contains normal, branched, unsaturated aliphatic acids with 6 to 11 carbon members. Most abundant is (E)-3-methyl-2-hexenoic acid. Both this compound and its (Z)-isomer are found in the aqueous phase hydrolysate and the aqueous phase incubated with bacteria. It is assumed that precursors are water soluble and converted to odoriferous compounds by the axillary flora (Zeng etal., 1992). 

The nomenclature of carboxylic acids and their derivatives was discussed in Section 7-6. Many carboxylic acids have trivial names and often are referred to as fatty acids. This term applies best to the naturally occurring straight-chain saturated and unsaturated aliphatic acids, which, as esters, are constituents of the fats, waxes, and oils of plants and animals. The most abundant of these fatty acids are palmitic, stearic, oleic, and linoleic acids. 

The reduction of oleic acid to stearic acid by this method is of technical importance and is one example of the reduction of unsaturated aliphatic acids to the corresponding saturated acids. 

Copolymers of isobutene with styrene (< 10 %) and isoprene (< 3 %) may be used for the manufacture of food contact materials. The following polymerizates and polymer mixes can be added to these polymerizates polyethylene, polypropylene, styrene-acrylonitrile mixed polymers, mixed polymers of ethylene, propylene, butylene, vinyl esters and unsaturated aliphatic acids as well as salts and esters and polybutene-1. 

PVC can be blended with numerous other polymers to give it better processability and impact resistance. For the manufacture of food contact materials the following polymerizates and/or polymer mixtures from polymers manufactured from the above mentioned starting materials can be used Chlorinated polyolefins blends of styrene and graft copolymers and mixtures of polystyrene with polymerisate blends butadiene-acrylonitrile-copolymer blends (hard rubber) blends of ethylene and propylene, butylene, vinyl ester, and unsaturated aliphatic acids as well as salts and esters plasticizerfrec blends of methacrylic acid esters and acrylic acid esters with monofunctional saturated alcohols (Ci-C18) as well as blends of the esters of methacrylic acid butadiene and styrene as well as polymer blends of acrylic acid butyl ester and vinylpyrrolidone polyurethane manufactured from 1,6-hexamethylene diisocyanate, 1.4-butandiol and aliphatic polyesters from adipic acid and glycols. 

There are also examples of bromofluorination of unsaturated aliphatic acids of the general formula... 

Similar studies carried out on the reduction of unsaturated aliphatic acids also show that rhodium and palladium function differently. In Tables III and IV data are presented on the reduction of various acids with these catalysts. With palladium it is noted that the rate of hydro-... 

Table I. Effect of Position of Double Bond on the Ionization Constant of Unsaturated Aliphatic Acids...

The contents of volatile acids of green and roasted coffee were studied by Wohrmann et al. (1997a). By means of simultaneous distillation/extraction (SDE), ion exchange and GC/FID, they identified and quantified 12 acids, including volatile saturated and unsaturated aliphatic acids which have a rancid and sweaty character. 

The identification of the numerous esters in the aliphatic ester fraction from tobacco and smoke led to the identification of a series of solanesyl and phy tosteryl esters of saturated and unsaturated aliphatic acids in tobacco and smoke (3296) and a similar series of P-amyrin esters in tobacco by Fredrickson (1230). 

Vorlander described unsaturated polyesters which were produced from ethylene glycol and maleic anhydride in 1894,- but commercial unsaturated polyesters were not Introduced until the 1920 s. The first commercial free radical-curable unsaturated polyesters were produced by Klenle and Hovey, who condensed dlfunctlonal glycols, such as ethylene glycol with phthalic anhydride and an unsaturated aliphatic acid such as oleic acid.- — - The name alkyd, which was derived from the prefix in alcohol and the suffix in incorrectly spelled "akyd" was used to describe these important polyesters. 

The fatty acid compositions of fungi have been extensively reviewed (Shaw, 1966 Wassef, 1977 Weete, 1980). Fungi produce saturated and unsaturated aliphatic acids of 10 to 24 carbons in chain length. Palmitic is the major saturated acid, oleic the main monoenoic acid and linoleic the most common polyunsaturated acid. 

Dicarboxylic acids found in polymeric esters unsaturated aliphatic acids determined in the ultraviolet by use of the strong bathochromic shift which occurs when concentrated H2SO4 is used as solvent e.g., crotonia acid has a maximum at 220 m/x in water, 235 m/x in H2SO4 Mixtures of terephthaloyl and isophthaloyl chlorides determined in ultraviolet region in iso-octane solution [ ]. 

Cobra venom contains an esterase capable of liberating the unsaturated aliphatic acid from lecithin, and leaving a residual lysolecifhin. Lysolecithins are powerful hsemolysins, and contribute by the fatal effect of injection of snake venom. They are antagonised by cholesterol, with which they form non-hsemolytic compounds. 

---