Silicic Acid Esters | Silicates | Polysilicates | Orthosilicates | Silane Passivating Agents

SiSiB® PC5440

Tetrabutoxysilane (TPOS) .
Synonym: Silicon Tetra-N-Butoxide;
Tetra Butyl Orthosilicate

Chemical Structure


The ethyl group of ethyl silicate is replaced by N-butyl, so the speed of hydrolysis is even slower than N-propyl silicate, and in addition to a cross-linking agent for silicon rubber, and a modifying agent for organic and inorganic resins, it can also be used as a heating medium or cooling medium by making it a condensate. There are also hopes for applications to electron donors in Ziegler-Natta catalysts.

Typical Physical Properties

Chemical Name: Tetra Butyl Orthosilicate
CAS No.: 4766-57-8
EINECS No.: 225-305-8
Empirical Formula: C16H36O4Si
Molecular Weight: 320.54
Boiling Point: 115°C [3mmHg]
Flash Point: 79°C
Color and Appearance: Colorless transparent liquid
Density [25°C]: 0.899
Refractive Index [25°C]: 1.4126 [20°C]
Purity: Min.98.0% by GC


SiSiB® PC5440 may be used as an inorganic binder for refractory fillers and pigments, like precision investment castings.

SiSiB® PC5440 may be used as a second backup casting coating. It cures faster than colloidal silica system.

SiSiB® PC5440 may be hydrolyzed to form silicon dioxide (silica).

SiSiB® PC5440 may be used as a binder in zinc-rich (corrosion resistant) coating.

SiSiB® PC5440 may be used as a starting material for sol-gel process.

SiSiB® PC5440 may be used as a crosslinking agent for silicone sealant.

SiSiB® PC5440 may be used as a drying agent in sealing compositions.

SiSiB® PC5440 may be used as a chemical intermediate.


Net weight 180Kg steel drum or 900Kg IBC container, for more details, please visit Packing Centre.

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