COUPSIL® VP 6411

Reaction product of organosilane Si 264™ (3-Thiocyanato-propyltriethoxysilane) and ULTRASIL® VN 2 (specific surface area 130 m2/g). The production consists of one hundred parts of ULTRASIL® VN 2 modified with eleven parts of Si 264™. Since the reaction between the organosilane and the silica is complete, COUPSIL® VP 6411 offers the advantage of a homogeneous modification with low moisture adsorption during storage and significantly lower development of ethanol during mixing and processing.
Advantages:
- Particularly rapid vulcanization accompanied by great scorch safety.
- Creates a high share of short sulfur crosslinks which leads to low compression sets and high heat stability.
- High cure rate of Si 264™ which furthermore permits nitrosamine-forming thiuram accelerators to be eliminated, partially or even completely, and replaced by other accelerators which are not affected by the nitrosamine formation.
- Leads to better vulcanization properties than the Si 69® containing COUPSIL® grades in polar polymers such as NBR.

Typical Applications

Mechanical rubber goods

Benefits at a glance

COUPSIL® VP 6411 is used as a reinforcing filler in rubber compounds. It reacts with unsaturated polymers during vulcanization under formation of covalent chemicals bonds. This imparts greater tensile strength, higher moduli, reduced compression set, increased abrasion resistance, and optimized dynamic properties.
It is used in many fields of the rubber industry in combination with white fillers and where optimum technical properties are required.
COUPSIL® grades form a group of silane-modified silica products used as reinforcing fillers in rubber compounds with a wide range of polymers such as NR, IR, SBR, BR, (Hal)-IIR, NBR, EPDM, EPM and blends thereof. The use of COUPSIL® products is particularly advantageous in short mixing series. COUPSIL® grades therefore effectively meet the requirements of the rubber-processing industry, particularly for mechanical rubber goods, which demand products that can be easily processed.
Great advantages of the COUPSIL® family:
- Pre-reacted products which eliminate the equipment-related complex in-situ modification of silica in the mixer.
- Reaction in presence of accelerators by forming rubber-to-filler bonds during vulcanization.
- Enabling tear and abrasion resistance on an elevated level = as well as excellent dynamic properties

Product Details

Further Information

Storage:

To ensure that product properties and application behavior remain unchanged, our precipitated silicas and silicates ought to be stored in closed and dry premises protected against exposure to volatile substances. Strict observance of optimum storage conditions ensures prolonged usability, nevertheless we recommend not to exceed a storage time > 24 months.
Forms of supply:
12,5 kg paper bags – 375 kg wooden pallet

Packaging:

12,5 kg bags on 375 kg wooden pallet

Shelf life:

min. 24 months

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