Knowde Enhanced TDS
Identification & Functionality
- Chemical Family
- CASE Ingredients Functions
- Composite Materials Functions
- Plastics & Elastomers Functions
- Technologies
- Product Families
Features & Benefits
- Labeling Claims
- Materials Features
- Product Highlights
- VPS 4721 is a novel high molecular weight epoxy functional silane which can be used in different applications.
- It has some advantages due to the high molecular weight compared to standard epoxy silane.
- In the presence of water, the methoxy groups of VPS 4721 hydrolyze to form reactive silanol groups which can bond to a variety of inorganic substrates.
- The organophilic glycidyl end of VPS 4721 can react with a suitable polymer. Hydrolysis of 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. VPS 4721 may be used in epoxy resins, phenolic resins, polyurethanes, PVAC, acrylates, polysulfides.
- Advantageous labeling compared to a standard epoxy silane
- Applications for color sensitive coatings and adhesives
- Long-term stability
- Better stability in polymer dispersions
- More than 60% less VOC compared to a standard epoxy silane
- High quality product
- Excellent reactivity
- Better adhesion on substrates, less water uptake.
- VPS 4721 can replace a standard epoxy silane and can be formulated with acrylic polymer dispersions resulting in a much better shelf life.
Applications & Uses
- Applications
- Compatible Polymers & Resins
- Application Characteristics
- 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 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 VPS 4721 can be used for
- filler dispersions
- viscosity reduction
- increased filler loading
- non yellowing
Properties
- Physical Form
- Appearance
- Colorless liquid
- Soluble in
- Alcohols, Ketones, Aliphatic and aromatic hydrocarbons
- Technical Data
| Value | Units | Test Method / Conditions | |
| Flash Point | min. 95 | °C | DIN EN ISO 2719 |
| Viscosity (at 20°C) | 750 - 1350 | mPa.s | DIN 53015 |
Technical Details & Test Data
- Stability
Stability of VPS 4721 compared to a standard epoxy silane in a 1 comp. acrylic dispersions.
VPS 4721 has a much better shelf life when added to a polymer dispersion.
- Reduced Water Uptake
- The water uptake of the coating based on formulation 1 and 2 with- out and with a standard epoxy silane or VPS 4721 are compared in the figure below.
- Coatings based on the pure formulation 1 and formulation 1 with 3% standard epoxy silane are having a much higher water uptake compared to the coating based on formulation 1 with 3% (w/w) VPS 4721.
- The water uptake of the coatings based on formulation 2 show less water uptake for the formulations containing standard epoxy silane or VPS 4721.
Water uptake of 1 comp. dispersion paints
Packaging & Availability
- Packaging Information
VPS 4721 is supplied in 25 kg, 180 kg drums and 1.000 kg bulk containers.
Storage & Handling
- Shelf Life
- 12 months
- 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.