Dynasylan® VPS 4721

Dynasylan® VPS 4721 is a bifunctional organosilane possessing a reactive organic epoxide and hydrolyzable inorganic methoxysilyl groups. The dual nature of its reactivity allows VPS 4721 to bind chemically to both inorganic materials (e.g. glass, metals, fillers) and organic polymers (e.g. thermosets, thermoplastics, elastomers), thus functioning as an adhesion promoter, crosslinking agent and/or surface modifier. Dynasylan® VPS 4721 is a colorless liquid. It is soluble in alcohols, ketones and aliphatic or aromatic hydrocarbons.

Principal: Evonik Corporation Silanes

Functions: Adhesion Promoter, Adhesion Promoter, Coupling Agent, Crosslinking Agent, Crosslinking Agent, Reinforcement, Sizing Agent, Surface Modifier, Surface Modifier

Chemical Family: Glass Beads & Fibers, Silanes

End Uses: Fiberglass Reinforced Composites, Foundry Resins, Polymer Dispersion, Primer

Compatible Polymers & Resins: Acrylates, Acrylics, Epoxies (EP), Phenolic Epoxy Resin, Polyurethanes (PU), Polyvinyl Acetate (PVA), Thermoplastic Elastomers (TPE)

Labeling Claims: Asbestos-free, Azo Compounds-free, Cadmium-free, Conflict Minerals-free, DEHP (Diethylhexylphthalate) Free, Dibutyl Phthalate (DBP)-free, Diisobutyl Phthalate (DIBP)-free, Formaldehyde-free, Hexavalent Chromium-free, Lead-free, Mercury-free, Polybrominated Biphenyls (PBB)-free, Polybrominated Diphenyl Ethers (PBDEs)-free, Polychlorinated Biphenyls (PCB)-free, Polychlorinated Naphthalenes (PCN)-free, Polyvinyl Chloride (PVC)-free

Features: Corrosion Resistance, Excellent Storage Stability, Good Electrical Properties, Good Mechanical Properties, Good Moisture Resistance, High Crosslinking, High Impact Strength, High Tensile Strength, Improved Flexural Strength, Improves Adhesion

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Enhanced TDS

Identification & Functionality

Features & Benefits

Applications & Uses

Coating End Applications
Compatible Polymers & Resins
Compatible Substrates & Surfaces
Composites End Use
Industrial Additives End Use
Markets
Applications
Product Applications

Dynasylan® VPS 4721 is a novel ingredient for special formulations and can be used in many applications in different industries.

Examples are:

  • Glass fiber/glass fabric composites: as a finish or a size ingredient
  • Foundry resins: as an additive to polyurethane resins
  • Sealants and adhesives: as a primer or additive
  • Mineral filled composites: for pretreatment of fillers and pigments or as an additive to the polymer
  • Paints and coatings: as an additive and as a primer for improving adhesion to the substrate, especially glass and metal as an additive for polymer dispersions

Important product effects that can be achieved through the use of Dynasylan® VPS 4721 as an additive include:

  • Improved mechanical properties, such as flexural strength, tensile strength, impact strength and modulus of elasticity
  • Improved moisture and corrosion resistance
  • Improved electrical properties, for example dielectric constant, volume resistivity better adhesion on substrates
  • Crosslinking of suitable polymers and polymer dispersions
  • Imporved storage stability of formulations

Dynasylan® VPS 4721 can be used for:

  • Filler dispersions
  • Viscosity reduction
  • Increased filler loading
  • Non yellowing

Properties

Physical Form
Soluble In
Product Reactivity
  • In the presence of water, the methoxy groups of Dynasylan® VPS 4721 hydrolyze to form reactive silanol groups which can bond to a variety of inorganic substrates.
  • The organophilic glycidyl end of Dynasylan® VPS 4721 can react with a suitable polymer.
  • Hydrolysis of Dynasylan® VPS 4721 can be catalyzed by organic acids such as acetic acid.
  • Examples of suitable inorganic substrates are glass, glass fibers, quartz, cristobalite and metals.
  • Dynasylan® VPS 4721 may be used in epoxy resins, phenolic resins, polyurethanes, PVAC, acrylates, polysulfides.

Packaging & Availability

Packaging Type

Principal Information

Group Principal Number
S000006
Principal

Storage & Handling

Storage Conditions
  • In the unopened container VPS 4721 has a shelf life of min. 12 months from delivery.
  • Please do not store above 35°C or in the direct sunlight.

Other

Appearance
Colorless liquid
Color (SDS)
Colorless to yellowish
Immiscible In (SDS)
Water
Item Number
USA/DOT UN Number
Not Applicable
Shelf Life & Stability
ValueUnitsTest Method / Conditions
Shelf Life12.0 momo
Physical Properties
ValueUnitsTest Method / Conditions
Flash Pointmin. 95.0 °C°CDIN EN ISO 2719
Viscosity700.0-1200.0 mPa.smPa.sDIN 53015 at 20°C
SDS Physical and Chemical Properties
ValueUnitsTest Method / Conditions
Boiling Point (SDS)min. 248.0 °F°F
Density (SDS)1.23 g/cm³g/cm³DIN 51757 at 20°C
Flash Point (SDS)min. 203.0 °F°F
Freeze Point (SDS)-89.0 °F°F
Ignition Temperature (SDS)707.0 °F°FDIN 51794
Viscosity (SDS)750.0-1350.0 mPa.smPa.sDIN 53019 at 25°C
pH (SDS)max. 6.0-DIN 38404-5