Enhanced TDS
Knowde-enriched technical product data sheet
Identification & Functionality
- Chemical Family
- Chemical Name
- Plastics & Elastomers Functions
- Chemical Formula
- C5H12O3Si
- CAS No.
- 2768-02-7
- EC No.
- 220-449-8
- Technologies
- Product Families
Features & Benefits
- Materials Features
- Benefits of Crosslinking
- Higher maximum use temperature
- Reduced deformation under load (creep)
- Improved chemical resistance
- Superior environmental stress crack resistance
- Increased abrasion resistance
- Improved impact strength
- Memory characteristics (shrink film, tubing)
- Improved impact strength
- Advantages of Silane Crosslinking over Radiation or Peroxide
- Low capital investment
- Low operating (energy) costs
- Higher productivity
- Processing versatility
- Thick, thin, or variable thicknesses possible
- Complex shapes possible
- Wilder processing latitude (control of premature crosslinking)
- Useful with filled composites
- Applicable to all polyethylene densities and copolymers.
Applications & Uses
- Markets
- Applications
- Compatible Polymers & Resins
- Plastics & Elastomers End Uses
- Plastics & Elastomers Processing Methods
- Applications
Polymer Modification:
AL121 is used to modify polyethylene and other polymers by grafting its vinyl group to the polymer backbone using a radical initiator, such as peroxide. This provides a polymer with pendant trimethoxysilyl groups that may be used as moisture-activated crosslinking sites via hydrolysis of the alkoxy groups followed by condensation of the resulting silanols.
Crosslinking of Silane-Grafted Polymers:
The reaction of Silane-grafted polyethylene to form a crosslinked or vulcanized polyethylene useswater to form the crosslinks. This technology is widely used around the world for commercial applications in wire and cable insulation, tubing, and other similar uses.
Properties
- Physical Form
- Appearance
- Colorless transparent liquid
- Typical Physical Properties
Value Units Test Method / Conditions Boiling Point (at 760mmHg) 122 °C - Density (25/25°C) 0.960 - 0.970 - - Molecular Weight 148.2 - - Purity min. 98.0 % - Refractive Index (at 25°C) 1.3905 +/- 0.0005 - -
Technical Details & Test Data
- Basic Reaction
The basic reaction sequence is as follows: polyethylene is reacted (grafted) with vinyltrimethoxysilane, using a peroxide initiator, in an extruder. The grafted polyethylene is then formed into a finished product, such as cable jacketing, wire insulation, or pipe. The forming step is usually done by a second extrusion, during which a catalyst for the moisture-cure step is added. Finally, the formed article is exposed to moisture or hot water to cause hydrolysis of the Silane and condensation to form crosslinks via Si-O-Si bond formation.