Bis[3-(triethoxysilyl)propyl]tetrasulfide

Bis[3-(triethoxysilyl)propyl]tetrasulfide Property

Boiling point:

250 °C

Density 

1.08 g/mL at 20 °C(lit.)

refractive index 

n20/D 1.49

Flash point:

91°C

storage temp. 

2-8°C, stored under nitrogen

form 

Liquid

Specific Gravity

1.095

Appearance

Colorless to light yellow Liquid

Water Solubility 

Miscible with toluene, primary alcohols, ketones, benzene, chlorinated hydrocarbons, acetonitrile, dimethylformaminde and dimethysulfoxide. Immiscible with water.

Hydrolytic Sensitivity

7: reacts slowly with moisture/water

BRN 

2062235

InChI

InChI=1S/C18H42O6S4Si2/c1-7-19-29(20-8-2,21-9-3)17-13-15-25-27-28-26-16-14-18-30(22-10-4,23-11-5)24-12-6/h7-18H2,1-6H3

InChIKey

VTHOKNTVYKTUPI-UHFFFAOYSA-N

SMILES

CCO[Si](OCC)(OCC)CCCSSSSCCC[Si](OCC)(OCC)OCC

CAS DataBase Reference

40372-72-3(CAS DataBase Reference)

EPA Substance Registry System

3,16-Dioxa-8,9,10,11-tetrathia-4,15-disilaoctadecane, 4,4,15,15-tetraethoxy- (40372-72-3)

Safety

Hazard Codes 

Xi

Safety Statements 

23-24/25

WGK Germany 

1

TSCA 

Yes

HS Code 

29309090

Hazard and Precautionary Statements (GHS)

Symbol(GHS)

Signal word

Warning

Hazard statements

H315Causes skin irritation

H319Causes serious eye irritation

H335May cause respiratory irritation

Precautionary statements

P261Avoid breathing dust/fume/gas/mist/vapours/spray.

P271Use only outdoors or in a well-ventilated area.

P280Wear protective gloves/protective clothing/eye protection/face protection.

Bis[3-(triethoxysilyl)propyl]tetrasulfide Chemical Properties,Usage,Production

Uses

Bis[3-(triethoxysilyl)propyl]tetrasulfide is a silylating coupling agent and modifier, and has been used in the design of a new generation of sustainable self-healing styrene-butadiene compounds.

Application

When used in rubber compounds, it produces these effects:
Coupling agent for non-black pigments;
Cure equilibrium for reversion resistance;
Curing agent for good heat aging.
Coupling Agent - With as little as 0.5 to 1.0 phr with clay fillers and 1.0 to 4.0 phr for silica pigments, BIS[3-(TRIETHOXYSILYL)PROPYL]TETRASULFIDE couples the non-black pigment and elastomers resulting in increases in modulus and increase in abrasion resistance.
Cure Equilibrium - BIS[3-(TRIETHOXYSILYL)PROPYL]TETRASULFIDE has four sulfur atoms positioned in the center. At cure temperatures, these participate with sulfur in producing polysulfidic crosslinks. The BIS[3-(TRIETHOXYSILYL)PROPYL]TETRASULFIDE replaces crosslinks broken during cure, resulting in reversion resistant, and with proper compounding, reversion free compounds. This is known as equilibrium cure. The dynamic flex characteristics, E.G., heat generation and crack growth, are dramatically improved.
Curing Agent - Removing all sulfur from the compound for NR, SBR, NBR and replacing it with BIS[3-(TRIETHOXYSILYL)PROPYL]TETRASULFIDE and certain thiuram accelerators, produces compounds with excellent heat aging characteristics in addition to the coupling effects. BIS[3-(TRIETHOXYSILYL)PROPYL]TETRASULFIDE is a silane coupling agent that has crosslinking and accelerator activity in rubber compounds.
Area of rubber industry where they would be beneficial
Footwear - Abrasion resistance | Cutting and chunking resistance | Flex life improvement
Rolls - Abrasion resistance | Aging resistance | Processing | Set reduction (better load bearing) | Reduced water swell | Lower hysteresis
Mechanical Molded Goods - Increased modulus | Better heat aging | Compression set reduction | Dynamic property improvement | Reduced swell to polar liquids | Filler substitution (non-black for black)
Hose - Improved abrasion on cover | Better heat aging | Increased modulus | Lower compression set | Improved adhesion to reinforcing elements
Solid Tires - Improved abrasion | Lower hysteresis | Higher modulus | Improved processing | Possibly better adhesion
Tires - Treads for abrasion, hot tear | Carcass for adhesion and/or filler substitution | Breaker (belt) stocks for adhesion
Belts Flat Belts - Increased abrasion | Improved reversion resistance | Reduced cost with clay substitution for black | Improved cord adhesion | Increased flex life and modulus
V Belts - Increased modulus | Improved abrasion | Longer flex life | Improved adhesion to reinforcing elements

Chemical Properties

Yellowish clear liquid

Uses

Bis[3-(triethoxysilyl)propyl]tetrasulfide is used in radial tires, rubber tire treads, carcass, tire walls, solid rubber tires and other rubber products. It acts as a chemical intermediate and as a cross linking agent. Furthermore, it acts as a coupling agent used to chemically modify silica surface. In addition, it serves as a curing agent for good heat aging.

Uses

Bis[3-(triethoxysilyl)propyl] tetrasulfide (TESPTS) is generally used as a crosslinking agent and reinforcing filler in the manufacturing of rubber. TESPT film provides corrosion protection to the metallic substrates. It is also used as a precursor in the synthesis of mesoporous organosilicas.