Stearates barium

Ultimately, as the stabilization reactions continue, the metallic salts or soaps are depleted and the by-product metal chlorides result. These metal chlorides are potential Lewis acid catalysts and can greatiy accelerate the undesired dehydrochlorination of PVC. Both zinc chloride and cadmium chloride are particularly strong Lewis acids compared to the weakly acidic organotin chlorides and lead chlorides. This significant complication is effectively dealt with in commercial practice by the co-addition of alkaline-earth soaps or salts, such as calcium stearate or barium stearate, ie, by the use of mixed metal stabilizers. 

Typically, soHd stabilizers utilize natural saturated fatty acid ligands with chain lengths of Cg—C g. Ziac stearate [557-05-1/, ziac neodecanoate [27253-29-8] calcium stearate [1592-23-0] barium stearate [6865-35-6] and cadmium laurate [2605-44-9] are some examples. To complete the package, the soHd products also contain other soHd additives such as polyols, antioxidants, and lubricants. Liquid stabilizers can make use of metal soaps of oleic acid, tall oil acids, 2-ethyl-hexanoic acid, octylphenol, and nonylphenol. Barium bis(nonylphenate) [41157-58-8] ziac 2-ethyIhexanoate [136-53-8], cadmium 2-ethyIhexanoate [2420-98-6], and overbased barium tallate [68855-79-8] are normally used ia the Hquid formulations along with solubilizers such as plasticizers, phosphites, and/or epoxidized oils. The majority of the Hquid barium—cadmium formulations rely on barium nonylphenate as the source of that metal. There are even some mixed metal stabilizers suppHed as pastes. The U.S. FDA approved calcium—zinc stabilizers are good examples because they contain a mixture of calcium stearate and ziac stearate suspended ia epoxidized soya oil. Table 4 shows examples of typical mixed metal stabilizers. 

The basic metal salts and soaps tend to be less cosdy than the alkyl tin stabilizers for example, in the United States, the market price in 1993 for calcium stearate was about 1.30— 1.60, zinc stearate was 1.70— 2.00, and barium stearate was 2.40— 2.80/kg. Not all of the coadditives are necessary in every PVC compound. Typically, commercial mixed metal stabilizers contain most of the necessary coadditives and usually an epoxy compound and a phosphite are the only additional products that may be added by the processor. The requited costabilizers, however, significantly add to the stabilization costs. Typical phosphites, used in most flexible PVC formulations, are sold for 4.00— 7.50/kg. Typical antioxidants are bisphenol A, selling at 2.00/kg Nnonylphenol at 1.25/kg and BHT at 3.50/kg, respectively. Pricing for ESO is about 2.00— 2.50/kg. Polyols, such as pentaerythritol, used with the barium—cadmium systems, sells at 2.00, whereas the derivative dipentaerythritol costs over three times as much. The P-diketones and specialized dihydropyridines, which are powerful costabilizers for calcium—zinc and barium—zinc systems, are very cosdy. These additives are 10.00 and 20.00/kg, respectively, contributing significantly to the overall stabilizer costs. Hydrotalcites are sold for about 5.00— 7.00/kg. 

ADCA is activated by zinc oxide, zinc stearate (strongly) and urea (slowly). Barium stearate, calcium stearate and triethanolamine, when added at 10 phr, moderately activate gas evolution from ADCA. They do not have very much effect on decomposition rate when the cure temperature is at 170 °C, but a marked effect above 180 °C. The rate of decomposition of ADCA is significantly influenced by the particle size of the additive. Effective dispersion and heat transfer through the particle can be a means of controlling the cell quality and the manufacturing method for the product. The correct particle size is selected to achieve the optimum balance between cure and cell development. 

Blodgett KB, Langmuir I (1937) Built-up films of barium stearate and optical properties. Phys Rev 51 964-982... 

Interestingly, in a situation where either magnesium stearate or stearic acid forms a component in the formulation, the organic medicinal compound which is acidic (amobarbital) cannot be extracted with NaOH solution for obvious reason that sodium stearate shall also be extracted along with the salt of the organic acid. Therefore, instead a saturated solution of Ba(OH)2 is employed thereby the insoluble precipitate of barium stearate may be discarded by filtration. 

Explosives such as PETN, RDX, HMX cannot be used as such for pressing because of their sensitivity and granular nature. The sensitivity is reduced considerably to safer limits by coating them with waxes or polymers. This process is called phlegmatizahon. In some cases, zinc stearate, barium stearate, graphite etc. 

Waxy ketones Synthetic esters Fatty acid amides Amide derivatives Imide condensation products Fatty alcohols Fatty acidis Metal soaps Palmitone cetyl stearate palmitamide stearanilide N-hexadecyl phthalimide stearyl alcohol stearic acid 12 hydroxstearic acid calcium resinate barium resinate calcium stearate barium stearate ... 

Barium Stearate. See under Stearates. Its use in smoke-producing compns was patented by J, DeMent, USP 2995526(1961),p6... 

Figure 9. Conductance of barium stearate multilayer membranes (109)...

M. Baer, Cast TNT/RDX/Wax/ Barium Stearate , PALR 126429, PicArsn, Dover... 

Example 13.6. Sodium salts such as NaCl exposed to a hot flame of a Bunsen burner emit bright yellow light of the wavelengths 589.0 nm and 589.6 nm (so-called Na D-lines) which is used as a hint for the presence of sodium in analytical chemistry. When we observe the reflection of this light from a LB film made of barium stearate (n = 1.491) on a glass substrate (n2 1.52) it appears completely dark for a film thickness of about 100 nm. 

Figure 3. Electron mean free path as a function of electron kinetic energy through organic materials. Key V, PMMA , poly(p-xylene) O, plasma polymerized fluorocarbon , barium stearate 0, cadmium arachidate and A, carbon. (Reproduced, with permission from Ref. 35.)...

DBTL = dibutyltin dilaurate BaSt = barium stearate... 

In general, the cadmium-containing samples have lost the most weight the barium stearate and bisphenol A samples have lost somewhat less than the cadmium samples but more than the controls. The rest of the samples are more or less indistinguishable on the basis of weight loss. 

The nature of the adsorbed monolayer depends on the interaction of the polar head group and the substrate surface. For example, if a glass microscope slide is raised up through a barium stearate monolayer spread on distilled water, the molecules in the film will be oriented with the hydrocarbon chains outwards, and hence the adsorbed film is hydrophobic 1I80. When a previously coated plate is dipped back into the surfactant-coated water, a second oriented layer will be deposited and the coated surfac m ain becomes hydrophilic as the head groups point outward. 

Ba(0H)2 8H20 was dissolved in stearic acid slowly, stirred and heated at a certain temperature. The barium stearate formed after some hours, to which a stoichiometric amount of tetrabutyl titanate (Ti(OC4H9)4) was added with stirring. The reaction mixture was kept at a certain temperature for hours to form white sol. The sol was dried in the air for 24 hours, and then the gel with a three-dimensionional net-like structure was formed. The BaTiOj powder was obtained by annealing the gel at 750 C in the air for 1 h by using a conventional furnace. 

Lesslauer, W. and Blasie, J. K. (1972). Direct determination of the stmcture of barium stearate multilayers by x-ray diffraction. Biophys. J. 72 175. 

SYNS CADMIUM BARIUM STEARATE OCTA-DECANOIC ACID, BARIUM CADMIUM SALT (4 1 1) (9CI) STEARIC ACID, BARIUM CADMIUM SALT (4 1 1)... 

CADMIUM AMIDE see CAD325 CADMIUM AZIDE see CAD350 CADMIUM BARIUM STEARATE see BAI800 CADMIUM BIS(N-AMYLDITHIOCARBAMATE) see CAD550... 

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