/pol'ee sul"fuyd/, n. Chem.
a sulfide whose molecules contain two or more atoms of sulfur.
[1840-50; POLY- + SULFIDE]

* * *

      any member of a class of chemical compounds containing one or more groups of atoms of the element sulfur linked together by covalent bonds. In inorganic compounds belonging to this class, these groups are present as ions having the general formula Sn2-, in which n is a number from 3 to 10 or more; these compounds usually are prepared by dissolving sulfur in solutions containing the sulfide ion, S2-. Sodium polysulfides are used in the tanning industry to remove hair from hides; lime–sulfur and sulfurated potash, prepared by heating sulfur with lime and potash, respectively, are mixtures containing polysulfides, used as insecticides and pesticides.

      Sodium polysulfide, in which n has a value around 4, has been used as a starting material in the preparation of rubbery or resinous synthetic organic substances called Thiokols. The molecules of these products consist of long chains in which polysulfide groups alternate with small organic groups capable of forming two covalent bonds. They can be converted by heating with zinc oxide to tough, resilient materials used to make hoses and linings for storage tanks and in other applications requiring resistance to chemical and physical attack; they also have been used as solid fuels for rockets. Thiokols also can be prepared as aqueous dispersions useful for forming protective coatings on surfaces such as wood, metal, or concrete or for preparing caulking compositions.

* * *

Universalium. 2010.

Look at other dictionaries:

  • Polysulfide — Polysulfīde, s. Schwefel …   Kleines Konversations-Lexikon

  • Polysulfide — Polysulfide,   Schwefelverbindungen.   …   Universal-Lexikon

  • polysulfide — [päl΄i sul′fīd΄] n. [ POLY + SULFIDE] a binary compound of sulfur containing more atoms of sulfur than the valence of the combining element requires …   English World dictionary

  • Polysulfide — Polysulfides are a class of chemical compounds containing chains of sulfur atoms. In their simplest form, polysulfides are anions with the general formula S n 2− and the structure −SSn 2S−. These anions are the conjugate bases of the hypothetical …   Wikipedia

  • Polysulfide — Anorganische Polysulfide (Polysulfane) sind Salze der Polyschwefelwasserstoffe. Sie enthalten als Anion ein zweifach negativ geladenes Polysulfid. Herstellung Alkalimetallpolysulfide werden durch Umsetzung von Alkalimetallmonosulfid mit… …   Deutsch Wikipedia

  • polysulfide — polisulfidas statusas T sritis chemija formulė Formulę žr. priede. priedas( ai) Grafinis formatas atitikmenys: angl. persulfide; polysulfide rus. персульфид; полисульфид …   Chemijos terminų aiškinamasis žodynas

  • polysulfide — noun Etymology: International Scientific Vocabulary Date: 1849 a sulfide containing two or more atoms of sulfur in the molecule …   New Collegiate Dictionary

  • polysulfide — noun any compound of general formula RSR having a chain of more than two sulfur atoms; any derivative of a polysulfane …   Wiktionary

  • polysulfide — poly·sul·fide (pol″e sulґfīd) 1. a sulfide that has two or more atoms of sulfur. 2. containing polysulfides; see under rubber …   Medical dictionary

  • polysulfide — poly·sulfide …   English syllables

Share the article and excerpts

Direct link
Do a right-click on the link above
and select “Copy Link”

We are using cookies for the best presentation of our site. Continuing to use this site, you agree with this.