Description

Tetramethylammonium Hydroxide Pentahydrate is a quaternary ammonium base supplied as a stable pentahydrate solid. This compound serves as a powerful, non-metallic organic base and phase-transfer catalyst, offering advantages over inorganic hydroxides in sensitive applications. It is a critical reagent for the electronics, pharmaceutical, and advanced materials industries, where high purity and consistent performance are paramount.

Application

• Semiconductor Manufacturing: As a key component in the formulation of tetramethylammonium hydroxide (TMAH) photoresist developers for silicon wafer processing.
• Organic Synthesis & Catalysis: Employed as a strong, non-nucleophilic base and phase-transfer catalyst (PTC) in alkylation, esterification, and hydrolysis reactions.
• Analytical Chemistry: Used as an eluent modifier in ion chromatography (IC) and as a titrant in non-aqueous acid-base titrations.
• Polymer & Material Science: Acts as a catalyst in the production of polycarbonates, epoxy resins, and other specialty polymers.
• Biochemistry & Pharmaceuticals: Utilized in protein sequencing, nucleic acid research, and as an intermediate in the synthesis of various active pharmaceutical ingredients (APIs).
• Surfactant & Dispersant Precursor: Serves as a starting material for the synthesis of quaternary ammonium surfactants and clay dispersants.

Basic Information

Product Name	Tetramethylammonium Hydroxide Pentahydrate
CAS No.	10424-65-4
Molecular Formula	C4H13NO · 5H2O or C4H23NO6
Molecular Weight	181.23 g/mol (Anhydrous basis: 91.15 g/mol)
Synonyms	TMAH Pentahydrate; Tetramethylammonium Hydroxide, Pentahydrate; N,N,N-Trimethylmethanaminium Hydroxide Pentahydrate; Ammonium, tetramethyl-, hydroxide, pentahydrate; TMAH 5H2O; Tetramethylammonium Hydroxide 5-Hydrate; Tetramethylazanium Hydroxide Pentahydrate
EINECS	233-903-9 (for the anhydrous form)

Quality Control

Our Tetramethylammonium Hydroxide Pentahydrate is manufactured under a strict quality management system. Each batch undergoes rigorous analytical testing to ensure it meets precise specifications for purity, assay, and impurity profiles, including critical metal ion content for electronics-grade material. A Certificate of Analysis (COA) detailing all test results is provided with every shipment to guarantee traceability and compliance with your application requirements.

Storage

Preserve in a tightly closed container, protected from light. Store in a cool, dry, and well-ventilated area at room temperature (15-25°C). This material is hygroscopic (moisture-sensitive) and must be kept in its original, sealed packaging until use to prevent absorption of atmospheric moisture and carbon dioxide, which can degrade product quality.

Specification

Item	Specification
Appearance	White to off-white crystalline solid
Identification (IR)	Conforms
Assay (Titration)	≥ 98.0 % (on anhydrous basis)
Water Content (KF)	40.0 - 45.0 %
Chloride (Cl)	≤ 0.01 %
Sulfate (SO4)	≤ 0.01 %
Heavy Metals (as Pb)	≤ 10 ppm
Iron (Fe)	≤ 5 ppm
Potassium (K)	≤ 10 ppm
Sodium (Na)	≤ 10 ppm

Note: Specifications can be tailored. Please contact us for the detailed technical data sheet of a specific grade.