Description

Bis[3-(Triethoxysilyl)Propyl]Tetrasulfide is a bifunctional organosilane coupling agent containing a tetrasulfide linkage. This compound is critically important for enhancing the adhesion and compatibility between inorganic fillers and organic polymer matrices. It is primarily needed by manufacturers in the rubber and tire industries for producing high-performance silica-reinforced compounds, as well as by formulators of specialty adhesives, sealants, and coatings.

Application

• Silica-Reinforced Rubber & Tires: Acts as a key coupling agent in "green tire" technology, significantly improving the reinforcement of silica in tread compounds to reduce rolling resistance and enhance wet grip.
• Mineral-Filled Elastomers: Improves the dispersion and bonding of fillers like clay and talc in various rubber goods, leading to better mechanical properties and durability.
• Adhesives and Sealants: Enhances the adhesion of polysulfide and other polymer-based sealants to glass, metal, and mineral substrates.
• Fiberglass and Composite Materials: Used as a sizing agent or primer to improve the interfacial bond between glass fibers and resin matrices in composite materials.
• Metal Surface Treatment: Functions as an adhesion promoter in corrosion-resistant primers and coatings for metals.
• Crosslinking Agent: Can serve as a sulfur donor and crosslinker in specific polymer modification and vulcanization processes.

Basic Information

Product Name	Bis[3-(Triethoxysilyl)Propyl]Tetrasulfide
CAS No.	40372-72-3
Molecular Formula	C18H42O6S4Si2
Molecular Weight	538.94 g/mol
Synonyms	Si-69; TESPT; Bis(3-triethoxysilylpropyl) tetrasulfide; 3,3'-Tetrathiodipropyl-bis(trimethoxysilane) (common misnomer); Tetrasulfido-1,6-bis(3-triethoxysilyl)hexane; Coupling agent Si-69; NXT silane; (Triethoxysilylpropyl) tetrasulfide; Bis(triethoxysilylpropyl) polysulfide
EINECS	254-896-5

Quality Control

Our production of Bis[3-(Triethoxysilyl)Propyl]Tetrasulfide adheres to stringent quality management protocols to ensure batch-to-batch consistency and performance reliability. Each lot is analyzed against key specifications for purity, sulfur content, and functional group integrity. Certificates of Analysis (COA) documenting these results are available upon request to support your quality assurance and regulatory compliance needs.

Storage

Preserve in a tightly closed container, protected from light. Store in a cool, dry, well-ventilated area at room temperature (15-25°C). This material is hygroscopic (moisture-sensitive); containers must be kept tightly sealed to prevent degradation from atmospheric moisture.

Specification

Item	Specification
Appearance	Clear, pale yellow to light brown liquid
Identification (IR)	Conforms
Assay (GC)	≥ 95.0%
Sulfur Content	22.0 - 24.0 %
Refractive Index (n20D)	1.485 - 1.495
Density (20°C)	1.07 - 1.09 g/mL

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