Zinc stearate powder

V.V. Zhukov, On the Explosive Concentration Limit of Iron, Sulfur and Zinc Stearate Powders and Their Mixtures , UsbPreduprezhdenie-VnezapnVozplomeneneniiPoroshkov i Vzryvov-GazodispersnSistem 1975, 139—41 CA 85, 8720(1976)... 

After leaving the solution to rest for 24 hours and filtering it, UV exposure was what made it effective Solutions not exposed to UV did not appear to work. The skin was also prepared by UV exposure, and the solution was applied five times, leaving each coat to dry before the next application. Urkov then applied an occlusive mask. This mask allowed the superficial layers to hyperhydrate by blocking transepi-dermal water loss (TEWL). The hyperhydration dissolved the salicylic acid that would have precipitated on the skin without occlusion and could not have penetrated, as only the acids in solution can readily penetrate the skin barrier. He then applied zinc stearate powder (which is antiseptic and anti-inflammatory). The erythema subsided in 5-6 days and exfoliation was superficial. The solution can be kept in the fridge for 10 days. 

Figure 2. Wide Angle X-ray (WAXS) pattern of 303-50 extruded fiber (right) and of zinc stearate powder (left) (adapted from Ref. 16).

Figure 3. Differential scanning thermograms of 303-0, 303-50 and zinc stearate powder in a second melting pass.

Figure 14. Scanning electron micrograph (SEM) of zinc stearate powder (technical).

A case study presented by Murray (1926) reported on an infant death due to bronchopneumonia resulting from inhalation, and possibly ingestion, of an unspecified amount of zinc stearate powder spilled from a container. However, it is unclear whether the death was due to the zinc content or... 

Zinc Stearate. Inhalation of zinc stearate powder resulted in aspiration bronchopneumonia in an infant (Murray 1926). However, it is unclear whether the bronchopneumonia resulted from the inhalation of zinc stearate powder specifically or from the inhalation of powders in general. 

Dry lubricants are usually added to the powder in order to decrease the friction effects. The more common lubricants include zinc stearate [557-05-17, lithium stearate [4485-12-5] calcium stearate [1592-23-0] stearic acid [57-11-4] paraffin, graphite, and molybdenum disulfide [1317-33-5]. Lubricants are generally added to the powder in a dry state in amounts of 0.25—1.0 wt % of the metal powder. Some lubricants are added by drying and screening a slurry of powder and lubricant. In some instances, lubricants are appHed in Hquid form to the die wall. 

Cellulose powder is now stirred into the cooled solution until the mass can still just be stirred.The contents of the flask are then transferred to a large beaker and more cellulose powder is kneaded in by hand (wear rubber gloves ) until a total of 35 g has been added.The crumbled mixture is dried for 24 h at 50 °C in the vacuum oven. Finally, the dried product is finely ground in a mortar, mixed with 1% of ammonium chloride and 1 % of zinc stearate (as lubricant) and crosslinked (cured) by heating to about 160 C for 10 min in a simple press at 300-400 bar. A thin transparent plate is obtained that is no longer soluble in or attacked by water this is more convincing if a small piece is allowed to stand overnight in a beaker of water. 

Zinc Stearate (or Octadecanoic acid zinc salt). Zn(Ci8H3502)2 mw 632,33 white, hydro-phobic powder, free from grittiness faint odor mp about 120°, about 130° (separate values) specific gravity 1.095. Sol in benz and hot common solvents such as chlf insol in ethanol, eth and w. Prepn is by reacting Na stearate with a soln of Zn sulfate. CA Registry No [557-05-1]. Zn stearate has an autoignition temp of 790°F and a flash pt of 530°F... 

Zinc stearate is primarily used in pharmaceutical formulations as a lubricant in tablet and capsule manufacture at concentrations up to 1.5% w/w. It has also been used as a thickening and opacifying agent in cosmetic and pharmaceutical creams and as a dusting powder. See Table I. 

Zinc stearate occurs as a fine, white, bulky, hydrophobic powder, free from grittiness and with a faint characteristic odor. 

Zinc stearate is used in oral and topical pharmaceutical formulations and is generally regarded as a nontoxic and nonirritant excipient. However, following inhalation, it has been associated with fatal pneumonitis, particularly in infants. As a result, zinc stearate has now been removed from baby dusting powders. 

The binders and lubricants added to the UO2 powder prior to granulation include materials such as polyethylene glycol (Carbowax), polyvinyl alcohol (PVA), paraffin, zinc stearate, or stearic acid. The additives may be incorporated dry (in amounts up to 3 wt %), or in solution (aqueous, in alcohol, or in carbon tetrachloride). The binders... 

Urkov used zinc stearate as a healing powder for 5 days after removing the occlusive mask. 

Major components of the pressed powder blusher include the powder phase and binder (or oil) phase. Components of the powder phase include mineral powder fillers such as talc (a magnesium silicate), mica (a magnesium ahuninum silicate), sericite (a form of hydrated mica), and kaolin (known as China clay). Talc is the most popular of all fillers used, as it tends to be virtually transparent depending on the particle size, and it is very soft to the touch. Although mica is also used extensively as a result of its transparency and smooth texture, it often exhibits a shiny appearance with skin application and has poor compression characteristics when used in a pressed powder. Modern non-oil control formulations rarely contain kaolin, as it tends to exhibit course texture, an extremely matte appearance, and excessive oil-absorption capabilities. Dry binders are also used to allow tlie compressed powder to retain form these include metallic soaps such as zinc stearate and magnesium stearate and... 

ZINC STEARATE (557-05-1) Combustible solid (flash point 530°F/277°C). Dust and powder form explosive mixture with air. Violent reaction with strong oxidizers, ammonium nitrate. Incompatible with nitrates. Flow or agitation of substance may generate electrostatic charges due to low conductivity. 

Zinc salt, C, I IwC4Zn. zinc undecylenate. Amorphous white powder, mp 115-116°. Resembles zinc stearate in appearance and physical properties. Can be prepd by dissolving zinc oxide in dil undecylenic acid and concentrating the solution. 

Calcium oxide Chlorite Chlorodiphenyl (54% Cl) Copper powder Feldspar Graphite Jute Melamine-formaldehyde resin Molybdenum disulfide PEG-4 dimethacrylate Sucrose distearate Urethane-acrylate resin Vinyltriethoxysilane Zeolite Zinc oxide Zinc stearate... 

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