Tetramethylammonium hydroxide

  • 75-59-2 (anhydrous)
  • 10424-65-4 ( pentahydrate )

Colorless, deliquescent, strong ammonia -like odor needles

Fixed

67-70 ° C

129 hPa ( 20 ° C)

Soluble in water to form strongly basic solutions

Pentahydrate

Risk

25 mg · kg -1 ( LD50, guinea pigs, s.c )

Template: Infobox chemical / molecular formula search available

Tetramethylammonium hydroxide ( TMAH) is a quaternary ammonium compound.

Properties

Chemical Properties

TMAH is a strong base. When heating TMAH decomposition takes place in trimethylamine and methanol.

Use

  • In the semiconductor manufacturing during the anisotropic etching of silicon
  • As a solvent in developing acidic photoresists
  • To prevent the massing of the nanoparticles in a ferrofluid
  • As a derivatization reagent (formation of methyl derivatives ) in chemical analysis
  • As a template in the preparation of the synthetic zeolite

Safety

TMAH results in severe irritation to chemical burns to the eyes, respiratory tract, lungs and skin.

The tetramethylammonium cation ( TMA) can damage nerves and muscles, which finally can lead to death within a very short time to respiratory paralysis.

CAS registry number PubChem Vapor pressure Dangerous Substances Directive (67/548/EEC)
766518
de