What are polysulfides used for?

Master Bond polysulfides are versatile synthetic elastomers that are used in the electronic, electrical, computer, metalworking, appliance, automotive and chemical industries. They can be used in a wide range of applications, such as: Aircraft fuel tank sealants.

How are polysulfides formed?

In addition to water and ammonia, the clouds in the atmospheres of the gas giant planets contain ammonium sulfides. The reddish-brownish clouds are attributed to polysulfides, arising from the exposure of the ammonium sulfides to light.

What is polysulfide made of?

Polysulfide rubber is a synthetic rubber that is a product of the polycondensation of dihalides of aliphatic compounds (for example, ethylene dichloride or propyl dichloride) with polysulfides of alkali metals (for example, Na2Sx, where x=2–4).

How do you make a sodium polysulfide solution?

Alternately you may take NaOH solution make it two halves. In one half pass hydrogen sulfide to get NaHS and then into it add the rest half of NaOH solution to create fresh Na2S . Into it you add elemental sulfur and stir. You will get polysulfide solution.

What is the meaning of polysulfide?

: a sulfide containing two or more atoms of sulfur in the molecule.

What is Polythioether?

Polythiols also called polythioethers are compounds with mercaptane or thioether functions in the backbone. They are commonly prepared by reacting sodium sulfide with dichloro compounds: Polythiols can also be prepared by reacting dithiols with aldehydes or ketones.

Is a monomer?

Monomer, a molecule of any of a class of compounds, mostly organic, that can react with other molecules to form very large molecules, or polymers. The essential feature of a monomer is polyfunctionality, the capacity to form chemical bonds to at least two other monomer molecules.

What is the chemical formula of sodium thiosulfate?

Na2S2O3
Sodium thiosulfate/Formula
Sodium thiosulfate (sodium thiosulphate) is an inorganic compound with the formula Na2S2O3. xH2O. Typically it is available as the white or colorless pentahydrate, Na2S2O3·5H2O. The solid is an efflorescent (loses water readily) crystalline substance that dissolves well in water.

What is the formula of sodium polysulfide?

Sodium polysulfide

Which is called polycentric?

: having more than one center (as of development or control): such as. a : having several centromeres polycentric chromosomes. b : characterized by polycentrism.

How do you remove polysulfide sealant?

12) To remove the uncured polysulfide sealant or silicone, place a wipe between you thumb and index finger. Place the wipe over the sealant and while pressing down flick you hand over the surface and up. Fold the wiper on itself and repeat until the surface is free of sealant residue.

What is polysulfide sealant?

Polysulfide sealants are designed for joints that need to withstand prolonged immersion in liquids. Typical applications include swimming pools, fountains, cooling towers, fuel and chemical storage tanks, wastewater treatment and petrochemical plants.

How are polysulfides used in the automotive industry?

Because of their solvent resistance, these materials find use as sealants to fill the joints in pavement, automotive window glass, and aircraft structures. Polymers containing one or two sulfur atoms separated by hydrocarbon sequences are usually not classified polysulfides, e.g. poly ( p -phenylene) sulfide (C 6 H 4 S) n .

How are Dihalides used to make polysulfide polymers?

Polysulfide polymers can be synthesized by condensation polymerization reactions between organic dihalides and alkali metal salts of polysulfide anions: Dihalides used in this condensation polymerization are dichloroalkanes (such as 1,2-dichloroethane, bis- (2-chloroethyl)formal (ClCH 2 CH 2 OCH 2 OCH 2 CH 2 Cl), and 1,3-dichloropropane).

How is sodium polysulfide produced in a solution?

Sodium polysulfide can be produced by dissolving sulfur in a solution of sodium sulfide. Alternatively they are produced by the redox reaction of aqueous sodium hydroxide with sulfur at elevated temperatures.

How are polysulfides used in the pulping of wood?

Polysulfide pulping is a variant of kraft pulping in which half or more of the sodium sulfide of kraft white liquor is first oxidized. This orange liquor has the ability to preferentially oxidize end groups of hemicelluloses, making them more stable to alkaline attack and resulting in higher yields of pulp from wood.