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Dynasylan® 6490

Dynasylan® 6490 is a concentrate of vinyl silane (oligomeric siloxane) containing both vinyl and methoxy groups. This nearly odorless, colorless, low-viscosity liquid acts as an excellent compatibilizer between inorganic fillers (such as kaolin, MDH, ATH) and organic polymers (including EPDM, EVA, PE).

Brand: Dynasylan (42 products)

Functions: Adhesion Promoter, Compatibilizer, Coupling Agent, Crosslinking Agent, Filler, Moisture Scavenger, Surface Modifier

Chemical Family: Organosilane

Labeling Claims: Low VOC

Compatible Polymers & Resins: Ethylene Propylene Diene Monomer (EPDM), Ethylene Vinyl Acetate (EVA), High-Density Polyethylene (HDPE), Polyethylenes (PE)

Enhanced TDS

Enhanced TDS

Knowde-enriched technical product data sheet

Identification & Functionality

Features & Benefits

Labeling Claims
CASE Ingredients Features
Materials Features
  • Dynasylan® 6490 is excellent as an adhesion promoter, dispersion and hydrophobation agent in mineral filled compounds.
  • In the presence of moisture, the methoxy groups of Dynasylan® 6490 hydrolyse to produce methanol and reactive silanol groups.
  • These silanol groups react with the filler via silicon- oxygen bridges. The vinyl functional groups of Dynasylan® 6490 react with the polymer phase in the presence of radicals.
  • The high boiling point of Dynasylan® 6490, together with its high flash point, gives it outstanding advantages with respect to safety and handling during processing.
  • From an environmental viewpoint it should be noted that the amount of released hydrolysis methanol (VOC) is significantly reduced compared to monomeric vinyl silanes.

Applications & Uses

Compatible Polymers & Resins
Plastics & Elastomers End Uses
Application Characteristics
  • A major field of application for mineral-filled compounds is the cable industry.
  • EPDM and EVA can be processed into highly filled cable compounds through the adhesion promoting and hydrophobising effect of Dynasylan® 6490.
  • The EPDM and EVA polymers with Dynasylan® 6490 are for the halogen-free, non-toxic, environmentally-friendly flame retardant cable compounds (HFFR) based on ATH and MDH.
  • In addition, Dynasylan® 6490 can be used in many other applications such as filler and pigment coating, dispersions etc. typical property improvements obtained by using Dynasylan® 6490 in filled polymers are:
    • improved filler dispersion.
    • good processability significantly.
    • reduced water-uptake.
    • excellent balance between tensile strength and elongation at break at a high level.
    • improved chemical resistance.
    • strongly reduced tendency to stress cracking.
    • higher impact strength.
    • higher abrasion resistance.


Physical Form
Colorless. low - viscous liquid
Nearly odorless
Technical Data
ValueUnitsTest Method / Conditions
Density (at 20°C)approx. 1g/cm³DIN 51757
Boiling Point (at 1013 hPa)min. 220°CASTM D-1120
Dynamic Viscosity (at 20°C)2 - 4mPa.sDIN 53015
Flash Pointapprox. 87°CDIN EN ISO 2719 (Pensky-Martens, closed-cup)
Silica Content (as SiO₂)approx. 54% w/wAN-SAA 0754

Regulatory & Compliance

Packaging & Availability

Packaging Type
Packaging Information
  • Dynasylan® 6490 is supplied in 25 kg, 200 kg drums and 1.000 kg containers.
  • The containers must remain tightly sealed and stored in a cool, well-ventilated place protected against moisture.

Storage & Handling

Shelf Life
12 months