Calcium soaps

Lipids present in the diet may become rancid. When fed at high (>4-6%) levels, Hpids may decrease diet acceptabiUty, increase handling problems, result in poor pellet quaUty, cause diarrhea, reduce feed intake, and decrease fiber digestion in the mmen (5). To alleviate the fiber digestion problem, calcium soaps or prilled free fatty acids have been developed to escape mminal fermentation. These fatty acids then are available for absorption from the small intestine (5). Feeding whole oilseeds also has alleviated some of the problems caused by feeding Hpids. A detailed discussion of Hpid metaboHsm by mminants can be found (16). 

The various lubricants formulated into PVC to improve the processing can also enhance the performance of the stabilizet. In pigmented apphcations, calcium soaps, eg, calcium stearate, ate commonly used as internal lubricants to promote PVC fusion and reduce melt viscosity. This additive is also a powerfiil costabilizer for the alkyl tin mercaptide stabilizers at use levels of 0.2 to 0.7 phr. Calcium stearate can significantly improve the eady color and increase the long-term stabiUty at low levels however, as the concentration increases, significant yellowing begins to occur. 

Salts of Organic Acids. Calcium salts of organic acids may be prepared by reaction of the carbonate hydroxide and the organic acid (9). Calcium lactate [814-80-2] is an iatermediate ia the purification of lactic acid from fermentation of molasses. Calcium soaps, soaps of fatty acids, ate soluble ia hydrocarbons, and are useful as waterproofing agents and constituents of greases (9). 

The sodium soaps of fatty acid form calcium soaps of such low solubdity that they act as their own budders. Initial soap additions precipitate the calcium ion and the soap added thereafter functions in soft water. At high temperatures, the calcium soaps are relatively soluble compared to calcium tripolyphosphate. Thus sodium tripolyphosphate (STEP) can budd (revert) soaps in a hot water wash. However, at low temperatures the relative affinity of STEP for calcium decreases so that STEP cannot budd soaps in a cold water wash. 

Thermotropic liquid-crystalline properties of different metal alkanesulfonates are studied by microscopy and X-ray diffraction [59]. Sodium soaps show smectic polymorphism of smectic A and smectic B phases. Ammonium soaps only show smectic A phases but polymorphism in the crystalline state. Calcium soaps show columnar mesophases. In Figs. 32 and 33 some textures and x-ray diffraction patterns are depicted. 

The ability to disperse the calcium soap formed from a given amount of sodium oleate has been studied for a number of a-sulfo fatty acid esters with 14-22 carbon atoms [28,30]. In principle, the lime soap dispersion property increases with the number of C atoms and the dissymmetry of the molecule. Esters with 14 C atoms have no dispersion power and in the case of esters with 15-17 carbon atoms the least symmetrical are the better lime soap-dispersing agents. However this property does not only depend on the symmetry but on the chain length of the fatty acid group. For example, methyl and ethyl a-sulfomyristate have better dispersing power than dodecyl propionate and butyrate. The esters with 18 and more carbon atoms are about equal in lime soap dispersion power. Isobutyl a-sulfopalmitate is the most effective agent under the test conditions. 

It is possible to separate a soap-LSDA dispersion by ultrafiltration through a polymeric membrane [33]. The filtrate contained sodium and some magnesium ions but no calcium soaps or LSDA. The separated substances on the membrane could be readily dispersed in water in which they retained a high degree of surface activity. 

Another way to obtain, under suitable conditions, stable dispersions of sur-factant-stabihzed nanoparticles consists in the direct suspension of some materials in w/o microemulsions. The formation of stable dispersions of rutile (size 80-450 mn) and carbon black (200-500 nm) in AOT// -xylene and of rutile, lead chloride, aluminium, antimony in solutions of calcium soaps in benzene has been reported [219,220],... 

Simple mixtures of this type have little resistance to water and are suitable for use only under the driest conditions. Many methods have been used for giving water resistance to these explosives, particularly to the milled varieties which tend to be less satisfactory in this respect than the hot mixed compositions. A small proportion of wax may be used, particularly if mixed in hot, but this tends to desensitise the explosive. Greater success is achieved by the addition of calcium soaps such as calcium stearate, in finely divided form. These also cause some desensitisation, but to an extent which is less marked in proportion to the degree of waterproofness achieved. 

In steatorrhea, the formation and precipitation of insoluble calcium soaps formed from calcium and fatty acid has been generally credited as the cause of reduced calcium and fat absorption. 

However, Patton and Carey (42) have suggested that calcium soap formation is a part of usual lipid digestion. Other research indicates that the availability of calcium from calcium soaps infused into rat intestines increases as fatty acid chain length decreases ans as degree of polyunsaturatedness increases (58). 

Fat absorption has been found to be less efficient in infants than in adult humans (60-63). Thus, the potential for formation and precipitation of calcium soaps inhibiting the absorption of calcium would appear to be greater. Furthermore, formulation of products to best promote both fat and calcium utilization by bottle fed infants would appear to be a desirable, obtainable objective. 

Grease is primarily a soap and lube oil mixture. The properties of grease are determined in large part by the properties of the soap component. For example, sodium soap grease is water soluble and not suitable for water contact service. A calcium soap grease, on the other hand, can be used in water service. The soap may be purchased as a raw material or may be manufactured on site as an auxiliary process. 

Boyd, O., Crum, C. L., and Lyman, J. F. (1931). The absorption of calcium soaps and the relation of dietary fat to calcium utilization in the white rat. /. Biol. Chem. 95, 29-41. Braun, M., and Weaver, C. M. (2006). A call to evaluate the impact of calcium-fortified foods and beverages. Nutr. Today 41, 40 7. 

Under contract with the Naval Weapons. Center, R. Stresau Laboratory, Inc, completed the sensitivity calibration of various design expls and two different series of VARICOMP expls (desensitized RDX) (Refs 2 to 7). The work differed from earlier similar efforts in that each expl was calibrated using donors of three diameters (50,100 and 200 mils). One of the VARICOMP mixes has a sensitivity to initiation nearly independent of diameter the other has a sensitivity to initiation highly dependent upon diameter. Reported upon are (1) RDX/ Calcium Stearate binary series (the same as used in the original work), (2) RDX/Calcium soap series, (3) CH-6, (4) PBXN-5, Type I,... 

Zinc soaps, which are complexes of long chain fatty acids, find similar applications in the curing and hardening of coatings to other transition metal soaps. A summary is available.123 The more important anions are 2-ethylhexanoate, naphthenate and stearate. Mixtures of zinc and calcium soaps are also effective stabilizers for poly(vinyl chloride).124 The complexes [Zn 0P(0)-(OBun)2 2] and [Zn SP(S)(OBun)2 2] both promote antiwear properties of lubricating oils.125... 

It is an everyday experience that calcium soaps have a low aqueous solubility while many surfactants with monovalent counterions have an extremely high solubility. As for other compounds, the solubility is to a great extent given by conditions in the solid phase, but for surfactants the strongly cooperative association produces the peculiar temperature dependence of solubility schematized in Fig. 2.8. The so-... 

Wherever possible, the soaps and surfactants were added to the natural rubber latex as dilute aqueous solutions. The cases where this was not possible were (a) ethylene oxide-fatty alcohol condensates of low ethylene oxide fatty alcohol mole ratio, and (b) sparingly-soluble fatty-acid soaps such as lithium laurate and calcium soaps. The former were added as pastes with water, the latter as dry powders. In all cases, the latex samples were allowed to mature for about three days at room temperature before their mechanical stabilities were determined. This allowed some opportunity for the attainment of adsorption equilibrium. 

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