Silanes & Alkyl Silanes
N-Octyltriethoxysilane | Manta L320
Manta L320 is n-octyltriethoxysilane (CAS 2943-75-1; INCI Triethoxycaprylylsilane), a monomeric alkyl silane used as a penetrating water repellent for concrete and masonry, a surface modifier for mineral fillers, and a surface treatment for cosmetic pigments and powders. Its ethoxy groups release ethanol on hydrolysis.
- Grade
- L320
- Chemical Name
- N-Octyltriethoxysilane
- CAS No.
- 2943-75-1
- INCI
- Triethoxycaprylylsilane
- EINECS
- 220-941-2
- Synonyms
- Triethoxyoctylsilane
- Form
- Colorless transparent liquid
Overview
Manta L320 is a clear, undiluted N-octyltriethoxysilane, a monomeric alkyl-functional organosilane. Its low molecular weight enables deep penetration into porous cementitious and mineral substrates.
In the presence of ambient moisture and an alkaline or acidic environment, the ethoxy groups hydrolyze to form reactive silanols, which chemically bond to the substrate. The resulting octyl-functional siloxane network provides durable, invisible water repellency without altering the substrate's natural breathability or appearance.
L320 shares its octyl chain with Manta L310, the trimethoxy grade, which hydrolyzes significantly faster and releases methanol rather than ethanol. Manta LO320 is also a triethoxy silane but carries a branched isooctyl group in place of the linear n-octyl chain.
For the reaction mechanism, how to use it and solvent selection, see our octyltriethoxysilane guide.
Key Features
- Durable, chemically bonded water-repellent barrier that significantly inhibits capillary water absorption
- Low viscosity and small molecular size for deep penetration into concrete and masonry
- Improves compatibility, wetting and dispersion of polar mineral fillers in non-polar polymers
- Good stability in highly alkaline environments such as freshly cast concrete
- Invisible water repellency that retains natural breathability and appearance
- Releases ethanol as the hydrolysis by-product
Cross-Reference
Manta L320 can be considered as an alternative to Momentive A-137, Dow OFS-6341, Evonik Dynasylan OCTEO and Shin-Etsu KBE-3083.
Trademarks are the property of their respective owners; no affiliation is implied.
Specifications
| Property | Typical Value |
|---|---|
| Appearance | Colorless transparent liquid |
| Purity (by GC, %) | 98.0 min |
| Specific Gravity (ρ20°C, g/cm3) | 0.874 ~ 0.884 |
| Refractive Index (nD 25°C) | 1.4120 ~ 1.4220 |
Typical values from the current Technical Data Sheet.
Applications
- Architectural waterproofing: when appropriately diluted in organic solvents, a penetrating water repellent for concrete, brick and natural stone that helps to limit freeze-thaw damage and chloride ion ingress
- Inorganic powder surface treatment: surface modifier for mineral fillers such as ATH, MDH and magnesium oxide, reducing viscosity and improving the mechanical properties of highly filled polymer compounds
- Cosmetics and personal care: under the INCI name Triethoxycaprylylsilane, a surface treating agent for pigments and powders such as titanium dioxide, zinc oxide, mica and talc, forming a durable lipophilic coating that enhances dispersion, sensory profile and wash-resistance in color cosmetics and sunscreens
Related applications: Concrete, Masonry & Stone Protection · Liquid Waterproofing & Construction · Paints & Coatings
Packaging & Storage
Supplied in 20 kg pail, 180 kg drum and 900 kg IBC.
Safety and Storage
Hydrolysis Reaction (CRITICAL): Manta L320 reacts with moisture to form cross-linked polysiloxanes while releasing ethanol as a hydrolysis byproduct. Ensure adequate ventilation during application and handling to prevent the accumulation of ethanol vapors.
Storage Conditions: Store in a cool, dry, and well-ventilated area. Keep containers strictly sealed against atmospheric moisture.
Shelf Life: 12 months from the date of manufacture when stored under recommended conditions in original, unopened containers. It’s shipped as non-hazardous material.
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Documents
- Technical Data Sheet · PDF Download TDS
- SDS and COA · on request Request Documents
Frequently Asked Questions
Can Manta L320 be used in cosmetics and sunscreens?
Yes. Under the INCI name Triethoxycaprylylsilane, L320 surface-treats cosmetic pigments and powders such as titanium dioxide, zinc oxide, mica and talc. It bonds covalently to the powder surface and forms a durable lipophilic coating that improves dispersion, sensory profile and wash-resistance in color cosmetics and sunscreens.
Does L320 remain effective in highly alkaline environments like fresh concrete?
Yes. The ethoxy groups hydrolyze in alkaline or acidic conditions to form silanols that bond chemically to the substrate, and the functional siloxane network shows good stability in highly alkaline environments such as freshly cast concrete.
What is released when L320 cures, and what precautions are needed?
Hydrolysis releases ethanol as a by-product while cross-linked polysiloxanes form. Ensure adequate ventilation during application and handling to avoid the accumulation of ethanol vapors, and keep containers sealed against atmospheric moisture.
Which mineral fillers benefit from L320 treatment?
L320 modifies polar mineral fillers such as ATH, MDH and magnesium oxide. It reduces compound viscosity and improves wetting, dispersion and mechanical properties in highly filled non-polar polymers such as polyolefins and rubbers.
Related Products
L320 is one step in the building protection formulation chain. One inquiry can cover the other raw materials in your formulation, with samples, technical documents, quotation and shipment handled together.
- Alkyl Silane Actives
- Emulsions & Pastes
- Siliconate Liquids & Powders
- Waterproof Coatings
Looking for a different purity, functional group, or a structure not listed here? Contact our technical team.
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