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Polysulfide

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Polysulfide 

a derivative of hydrogen polysulfide, H2Sx where x = 2–9. Polysulfides are solids, ranging in color from light yellow to brownish red, with a specific, unpleasant odor.

Polysulfides of ammonia, alkali metals, and alkaline-earth metals are known—for example, potassium forms K2S2, K2S3, K2S4, K2S5, and K2S6. Sulfur atoms are arranged in an —S—S—S— chain in polysulfide molecules. The melting point of polysulfides is lower than that of sulfides. For example, the melting point of K2S is 835°C, whereas that of K2S6 is 183°C. Polysulfides are chemically very unstable; they decompose upon heating to form sulfides. In the presence of acids they liberate H2Sx which decomposes immediately into H2S and S.

Polysulfides are produced by fusing sulfides, hydroxides, or carbonates with sulfur; sulfur may be added to an aqueous sulfide solution. Polysulfides of calcium and barium are used against agricultural pests. Barium polysulfide is an effective depilatory.
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Proxan develops, produces and sells sealants made from polysulfide and two-component polyurethane.
The construction chemicals market: consolidation continues to be a ... by Wright, Tim / Coatings World
[ILLUSTRATION OMITTED] THE NEW ASSEMBLIES USE A POLYSULFIDE SEALANT AND CAN BE IDENTIFIED BY A MACHINED V-CUT ON THE SPINDLE.
New and improved road arms. (M1-Series Tanks ...) by PS, the Preventive Maintenance Monthly
Given that the caulking material is at least 30 years old, it may be degraded to the point that the PCBs, which were plasticizers in the original polysulfide polymer formulations, can be mobilized into solution.
Soil contamination from PCB-containing buildings by Weymouth, George A. / Environmental Health Perspectives
 
 
 
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