Product Introduction
N-Octadecyltrichlorosilane, commonly referred to as OTS (CAS 112-04-9), is an organosilicon compound featuring a long 18-carbon alkyl chain attached to a reactive trichlorosilyl group. It appears as a colorless to light yellow fuming liquid with a sharp, pungent odor. N-Octadecyltrichlorosilane (CAS 112-04-9) is a premier reagent used to modify surface properties, specifically for the formation of densely packed Self-Assembled Monolayers (SAMs). By reacting with surface hydroxyl groups on substrates like silica or glass, it creates a robust, chemically bonded hydrophobic layer. This makes it indispensable in advanced nanotechnology, microelectronics, and high-performance chromatography.
Product Selling Points
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Superior Hydrophobicity: The C18 long-chain structure provides a highly water-repellent surface with high contact angles.
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High-Quality SAM Formation: Known for producing one of the most ordered and stable self-assembled monolayers available in nanotechnology.
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Excellent Surface Bonding: The trichlorosilane group forms strong, covalent siloxane bonds with hydroxylated surfaces for long-lasting durability.
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Low Moisture Content: Strictly controlled production environment ensures minimal hydrolysis, maintaining the high reactivity of the fuming liquid.
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Research and Industrial Grade: Available in high-purity grades suitable for both precision laboratory research and large-scale industrial surface treatment.
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Optimized for Microelectronics: Effectively reduces surface energy and friction in MEMS devices and semiconductor wafers.
Applications
Self-Assembled Monolayers (SAMs) This product is widely used in nanotechnology to create highly ordered monolayers on silicon wafers and glass, serving as a model system for studying molecular organization and surface friction.
Hydrophobic and Anti-Stiction Coatings It is applied to Micro-Electro-Mechanical Systems (MEMS) to prevent stiction (static friction) and to provide a protective, water-repellent barrier on precision optical components.
Chromatography Column Modification OTS is a key reagent for the modification of silica gel in HPLC columns, creating the “C18” stationary phase required for reversed-phase chromatography.
Semiconductor Surface Passivation In electronics, it is used for the surface passivation of transistors and sensors to improve device stability and protect against environmental moisture.
Packaging
Standard industrial packaging options for N-Octadecyltrichlorosilane include:
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25kg specialized fluorinated HDPE pails or plastic-lined steel drums.
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200kg heavy-duty steel drums for industrial-scale coating applications.
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1kg or 5kg amber glass bottles or metal canisters sealed under dry nitrogen for lab use.
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All containers are nitrogen-blanketed to ensure the material remains moisture-free during transit.
Storage
N-Octadecyltrichlorosilane is highly moisture-sensitive and corrosive. It must be stored in a cool, dry, and well-ventilated dedicated chemical warehouse. Containers must be kept tightly sealed under an inert gas (nitrogen or argon) at all times. Protect from moisture and humidity, as contact with water releases toxic and corrosive hydrogen chloride (HCl) gas. Store away from strong bases, alcohols, and oxidizing agents.
Related and Similar Products
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N-Octyltrichlorosilane – CAS 5283-66-9
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Dodecyltrichlorosilane – CAS 4484-72-4
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Hexadecyltrichlorosilane – CAS 5894-60-0
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N-Octadecyltrimethoxysilane – CAS 3069-42-9
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N-Octadecyltriethoxysilane – CAS 7399-00-0
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Trimethylchlorosilane (TMSCl) – CAS 75-77-4
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Dimethyldichlorosilane – CAS 75-78-5
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Perfluorooctyltrichlorosilane – CAS 78560-45-9
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Decyltrichlorosilane – CAS 13829-21-5
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Hexamethyldisilazane (HMDS) – CAS 999-97-3
FAQ
Surface Modification and SAMs
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Q1: What is the best solvent to use for OTS surface modification? A1: Anhydrous toluene, hexane, or cyclohexane are the most common solvents. The solvent must be extremely dry to prevent the OTS from polymerizing in solution before it reaches the surface.
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Q2: How do I ensure a high-quality monolayer? A2: The substrate (like a silicon wafer) should be thoroughly cleaned (e.g., Piranha solution or UV-Ozone) to maximize surface hydroxyl density before immersion in the OTS solution.
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Q3: Can OTS be used on plastics? A3: It is most effective on substrates with hydroxyl groups (glass, silica, metals with oxide layers). Most plastics require a pre-treatment (like plasma oxidation) to create the necessary bonding sites.
Safety and Handling
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Q1: Why does the liquid fume when the bottle is opened? A1: The trichlorosilane group reacts instantly with ambient humidity to release hydrogen chloride (HCl) gas, which forms visible acidic fumes.
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Q2: What is the hazard classification for shipping? A2: It is classified as a Corrosive Liquid (UN 1801, Class 8, PG II) and requires specialized hazardous materials handling and labeling.
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Q3: How should I handle an OTS spill? A3: Do not use water. Cover with dry sand or an inert absorbent. Neutralize residual acidity with sodium bicarbonate only after the bulk of the liquid has been absorbed and removed.
