Back in the early decades of silicon chemistry, researchers looked to the alkoxysilanes for ways to change the nature of glass, ceramics, and polymer surfaces. Materials scientists realized the long carbon chains on silanes could bring hydrophobicity or other qualities unfamiliar to glass or silicon-based materials. N-Hexadecyltrimethoxysilane (HDTMS) grew out of this search for surface-active silanes: its long, 16-carbon hydrocarbon tail emerged from the need for durable water-repellent treatments in textiles and construction. Early work focused on how to use this molecule in sol-gel chemistry, where its ability to co-condense with other silanes provided hydrophobic coatings on glassware, silica, and other mineral surfaces. As labs pushed for stronger, more versatile hydrophobic agents, HDTMS and its analogs replaced older, less stable repellents, bridging a gap between lab-scale innovation and industrial practicality.
Today, N-Hexadecyltrimethoxysilane stands out for its unique two-part structure: a trimethoxysilyl head connected to a straight sixteen-carbon tail. This layout means HDTMS binds tightly to siliceous surfaces, transforming the wettability and chemical resistance of everything it touches. Most people working with this chemical see it as a colorless to pale yellow liquid. Its faint, characteristic odor may fill the air during handling, and it’s stored in tightly sealed containers to keep it away from water vapor and reactive groups that could trigger untimely hydrolysis. Among silane coupling agents, HDTMS gets special attention in surface science, not for bulk properties, but for what it does at the boundary where one material meets another.
On the lab bench, N-Hexadecyltrimethoxysilane acts much like a light, oily fluid, with a boiling point higher than many solvents but a much lower vapor pressure than lighter silanes. Its solubility profile tells you how to work with it: it resists water but mixes well with common organic solvents such as toluene or chloroform. This lipid-like character, thanks to the sixteen-carbon chain, allows it to migrate to air or oil interfaces, reducing surface energy and pushing water away. Chemically, HDTMS stands out for its trio of methoxy groups, which react rapidly with moisture to form reactive silanols—the real players in surface modification. This trait demands careful storage and handling, since even a little humidity can kick off unwanted hydrolysis, clogging valves or nozzles in spray equipment and ruining shelf life.
Most manufacturers list N-Hexadecyltrimethoxysilane by its purity, usually above 95%, while trace amounts of methanol and unreacted halides make up the remainder. Safety labels name it as “HDTMS,” “C16 Silane,” or “Hexadecyltrimethoxysilane.” Labels also emphasize critical transport information: store in a cool, dry place away from acid or alkaline agents, avoid open flames, and use with adequate ventilation. Material safety data sheets (SDS) outline flammability, skin and eye irritancy, and environmental concerns that come up if spills head for storm drains. In any regulated setting, workers keep an eye on ventilation and handle the substance with care, using gloves and goggles.
Commercial synthesis usually begins with hexadecyl chloride or bromide, which reacts with a sodium or potassium silanolate or directly with trimethoxysilane under catalytic or anhydrous conditions. This route demands strict control over temperature and moisture, since side reactions can form gels, tars, or short-chain byproducts. Modern processes make room for continuous flow equipment, precision dosing, and high-vacuum distillation to purify the final product. Labs sometimes lean on classical batch methods, but industrial scale-up relies on engineering controls that reduce waste and keep operators safe from exposures to flammable or caustic intermediates.
What makes N-Hexadecyltrimethoxysilane so valuable is the flexibility it brings to surface chemistry. Its methoxy groups switch over to silanols with a splash of water, and these bind tightly to glass, metals, metal oxides, and certain polymers. After anchoring, the long alkyl tail points outward, and the treated surface repels water, oils, and dirt. In research, scientists sometimes “co-graft” HDTMS with other functional silanes to give glass or nanoparticles both hydrophobic and reactive surfaces. Chemical modifications include partial hydrolysis, end-group transformations, or incorporation into hybrid organic-inorganic matrices for next-gen coatings. The molecule’s basic structure stays intact across a range of pH environments, giving it an edge in harsh chemical and weathering tests.
Depending on the source, buyers may see this chemical listed under several names. “Hexadecyltrimethoxysilane” is its IUPAC name; “n-Hexadecyltrimethoxysilane” calls out its linear chain; trade names like “Dynasylan 9116,” “Silquest A-1616,” or “C16 Silane” point to suppliers or brand-specific grades. In practice, all these refer to the same base molecule, and suppliers provide certificate of analysis (CoA) paperwork linking these names back to the product’s batch and purity specs.
In my own work handling organosilanes, hazard awareness starts early. N-Hexadecyltrimethoxysilane can cause irritation if it hits exposed skin or eyes, and inhalation of its vapors triggers coughing or headaches in poorly ventilated labs. Direct contact with acids or bases can speed up hydrolysis, so personnel use fume hoods, nitrile gloves, and chemical splash goggles. Facilities equipped for silane work install explosion-proof ventilation and keep spill kits for absorbing leaks from pumps or pipelines. Training covers fire risk, since volatile alcohols may form during large spills, and workers know to avoid drain disposal due to aquatic toxicity. Regular audits, safety drills, and environmental monitoring back up these daily controls, helping keep both people and the environment safe as demand for HDTMS and related products grows.
Perhaps the greatest strengths of N-Hexadecyltrimethoxysilane show up in the coatings and surface modification sector. In glass and ceramics manufacture, it delivers long-term water repellency that keeps windows and electronic displays clear under harsh weather. Construction firms trust it for treating building sand, stone, or concrete, where it curbs water absorption, stops freeze-thaw cycling, and blocks corrosive salts. Researchers found that the molecule’s long tail also shields nanoparticles in paints and composites from moisture, UV, and stains. Textile manufacturers lean on HDTMS for easy-to-clean, stain-resistant clothing and upholstery, while electronics makers put it to work as an anti-fingerprint and anti-fouling layer on touchscreens. Agriculture and packaging sectors experiment with crosslinking HDTMS in biodegradable plastics, where hydrophobic treatment extends shelf life and blocks microbial growth. These benefits only appear with careful control of process conditions—over-saturate a surface, and you lose adhesion or optical clarity.
Every year, research teams take new approaches to HDTMS application and modification. Recent work explores how mixed silane coatings can balance hydrophobic and hydrophilic sites on medical devices, improving antifouling without reducing biocompatibility. Meanwhile, nanotechnology labs assemble “superhydrophobic” surfaces, templating HDTMS onto etched silicon or aluminum that guides water droplets away, cleaning itself with a single drop of rain. Scientists pursue greener, lower-waste synthesis methods to minimize byproducts, and machine learning models predict how HDTMS coatings will stand up to marine or desert exposure. Industrial researchers push for faster curing and lower temperature processes, aiming to bring the same water-repellent power to plastics, rubbers, and light metals without expensive oven treatments. This research matters for anyone seeking sustainable, durable surfaces that protect critical infrastructure from weather, pollution, and handling.
Hazard studies on N-Hexadecyltrimethoxysilane point to low acute toxicity but underline both skin irritancy and risks to aquatic life. As with all organosilanes, hydrolysis releases methanol, and exposure to large amounts brings headaches, nausea, and in severe cases, nervous system problems. Chronic exposure data remain limited, so workplace monitoring and job rotation limit risks for high-frequency users. Environmental studies note slow biodegradation in water and soil, where the persistent hexadecyl tail can bioaccumulate or foul sensitive ecosystems. Modern labs invest in containment, solvent recycling, and air scrubbing to cap off any emissions. Ongoing studies track the breakdown products and how they interact with bacteria, fish, and plants. Careful stewardship by both industry and academia will shape regulations as production rises and new uses emerge in consumer products.
Rising demand for durable, weatherproof materials keeps finding new opportunities for N-Hexadecyltrimethoxysilane. As cities battle climate change, construction and civil engineering seek water-repellent treatments that last decades and stop costly repairs. The electronics industry asks for robust, anti-fingerprint coatings thinner than a strand of hair. Consumer product designers want eco-friendly water-repellents for everything from sneakers to tents, putting pressure on manufacturers to deliver HDTMS with minimal waste and energy input. Regulatory agencies pay close attention to both worker safety and environmental impact, and chemistry labs double down on greener synthesis as a result. With every breakthrough, HDTMS moves closer to everyday products, not just niche surfaces in aerospace or building, and my own experience tells me this chemical’s future depends on smart policy, cutting-edge research, and respect for its chemistry at every scale.
N-Hexadecyltrimethoxysilane looks like a mouthful, but this compound shows up quietly in places people don’t usually think about. If you’ve ever wondered how windows seem to shrug off rain, or how your smartphone’s fingerprint-resistant screen stays so easy to clean, you’ve already brushed shoulders with its real-world impact. Chemistry can be intimidating or seem disconnected from daily life. In this case, though, the science stitches together a thread running from industrial materials to objects you use every day.
Picture rain rolling off a fresh waxed car. N-Hexadecyltrimethoxysilane helps make glass, ceramics, and even metals act like a waxed surface. It doesn’t just sit on materials; it forms bonds that keep water, oil, and dirt from sticking. A long carbon tail in the molecule acts a lot like the soft side of Velcro, repelling water and grime. Architects and engineers rely on this when they order glass for skyscrapers or develop protective coatings for stone and steel.
Using this compound, coatings go on surfaces so that they actively resist fingerprints, smudges, and corrosion. A science-backed report in the Journal of Materials Science showed glass treated with it repels water droplets far better than untreated samples. This isn’t about laboratory curiosity — it helps companies cut down on cleaning costs and improve product life. I’ve watched this play out first-hand. Visiting my friend’s research lab, I saw how a researcher spilled wine on tiles coated with this silane. The drops just beaded up and rolled off, no stain left behind.
I once worked on a collaborative project with a factory that produced electronic touch screens. The technical team explained that to get a truly durable screen — one that you could swipe hundreds of thousands of times — meant treating the surface with something that connected glass and polymer layers together. N-Hexadecyltrimethoxysilane makes the glue between those two layers stick better, preventing the delamination that kills expensive devices. Its use doesn’t end at electronics. Designers use it to strengthen paints, adhesives, and even dental materials. Reports from ACS Applied Materials & Interfaces highlight how adding a small amount increases the durability and chemical resistance of everyday items.
Science improves lives, but every chemical has a footprint. While there’s plenty of enthusiasm about making surfaces cleaner and products more durable, regulators do keep an eye on the safety of these treatments. Manufacturers need tight controls to prevent the release of silane vapors, which can irritate eyes and lungs. Training and proper ventilation go a long way, and consumer-facing products made with N-Hexadecyltrimethoxysilane don’t pose a big risk, since the end result binds tightly to the base material.
Calls for greener chemistry pop up everywhere now. The silane coating industry isn’t immune. Research teams push for ways to use less of the chemical or to recycle it during manufacturing. Groups like the EPA are tracking the long-term effect on water systems and waste, urging companies to keep waste streams clean. Greater transparency and tighter safety rules help strike a balance between robust coatings and environmental responsibility.
N-Hexadecyltrimethoxysilane rarely commands headlines, but it quietly shapes the performance and life of products people touch every day. Whether it’s a touchscreen, a building exterior, or a stain-resistant floor, this compound protects against the messes and mishaps of daily life. Innovation, responsible use, and honest reporting on impacts will determine how it continues to serve both industry and community needs.
Working in a research lab, you get a feel for how a single overlooked bottle can invite trouble. N-Hexadecyltrimethoxysilane isn’t just another chemical on the shelf. Its molecule packs a punch with reactive silane groups and a hydrocarbon tail, making it handy for modifying surfaces and offering hydrophobic properties. But with that utility comes risk, especially if people treat storage like an afterthought.
Poor storage doesn’t only put experiments at risk. I’ve watched researchers scramble because a bottle sweated off moisture or released fumes. That cost time, and sometimes, it made the bench a little less safe. Storing this silane in a sealed glass container keeps air and moisture away from those reactive sites. People skip this step, and the compound starts hydrolyzing, gumming up with silanols and methanol. It doesn’t take much for a whole batch to turn useless—or even dangerous.
Extremes don’t favor N-Hexadecyltrimethoxysilane. Storing it at room temperature away from heat sources avoids the risk of thermal decomposition, which can release methanol vapors. That’s a tricky byproduct, flammable and irritating. Flammable storage cabinets exist for good reason, and I’ve seen too many cases where omitting this basic precaution led to headaches down the road.
Humidity will trigger slow decomposition. Despite often looking like a stable liquid, exposure to natural room moisture starts a slow process that eats up the silane’s usefulness. Desiccators become more than just lab relics—they’re a frontline defense. The best practice: keep the bottle closed tight, inside a dry space. Once, after spending a summer with a bottle left slightly open, we had to rerun three weeks’ worth of trials because the functional group degraded with air exposure.
Handling this silane needs more than just gloves and a mask. Venting is essential. Anyone who’s tried pipetting it in a cramped closet knows how quickly the fumes become noticeable. At scale, those vapors mean real health risks—prolonged inhalation can cause irritation, and no lab wants to explain an avoidable accident. Fume hoods and proper PPE become the sort of thing you check before starting, not after a spill.
To reduce risks, make sure everyone understands the importance of labeling. Generic “silane” scrawled on a bottle won’t cut it. Accurate names keep new team members from reaching for something reactive when they’re half-asleep during a night shift. Avoiding cross-contamination also helps maintain product quality, and it doesn’t take more than a dedicated pipette and a zero-tolerance approach to dirty gloves.
A lot of trouble can be sidestepped by building habits, not just following checklists. Don’t rely on memory for expiry dates—track them, especially after opening. Consider smaller stock bottles instead of returning to the main container again and again. Training shouldn’t be a once-a-year slideshow. Pair new researchers with folks who have handled the chemical for years, so best practices become second nature.
Smart storage and handling let labs save money, protect staff, and keep experiments on track. Knowledge spreads when mistakes are shared, not hidden, so keep open lines in the daily scramble. That’s how you turn protocol into real safety—and protect the integrity of your work.
N-Hexadecyltrimethoxysilane crops up in labs and factories for things like surface treatments, not just for fun chemistry experiments. It adds unique properties to glass, ceramics, and plastics, and is valued for making surfaces repel water or oil. Most people never encounter this stuff outside a chemistry lab, but in these settings, thinking about safety makes sense. The ingredient-sounding name shouldn't lull anybody into a false sense of security. Under the microscope, N-Hexadecyltrimethoxysilane still brings hazards that need respect.
This compound has a long silane tail, making it less volatile than some notorious solvents. It won't just disappear from a table or evaporate if spilled. That sounds harmless at first, but low vapor pressure can have a dark side; the liquid will hang around, waiting for a careless hand. If it touches skin, irritation shows up quickly. Direct exposure brings painful rashes or redness, especially for those of us who forgot to grab gloves in the past. Eyes get hit hard too—splash some in your eye, and you’ll wish you had paid attention to the safety sheet. Inhalation rarely pops up outside lab accidents, yet spraying it around opens the door to headaches, dizziness, or feeling sick to your stomach.
N-Hexadecyltrimethoxysilane wins little praise for safety on the flammability scale. Once released near an ignition source, it catches fire as easily as gasoline. Plenty of people ignore the danger in mix rooms or while pouring high volumes—one static spark can do real harm. Lab burns from silanes don’t heal quickly. For long-term effects, the data thins out. No mountains of science show cancer links, but any chemical able to irritate the lungs or skin so violently deserves cautious handling.
Training makes a difference. My first job as a chemist, I saw a colleague ignore splash goggles for “just a quick pour.” He spent the afternoon washing his eyes at an eyewash station. That type of experience sticks with you. In companies with good protocols, N-Hexadecyltrimethoxysilane lives in a vented hood, lab coats seal wrists, and gloves are standard. The Material Safety Data Sheet spells out the essentials: keep containers closed, avoid inhaling vapors, wash hands after use, and don’t store near heat. These aren’t optional superstitions—they stop injury before it starts.
Better labeling and information reduce surprises. Some companies have started clearer hazard pictograms and require routine refresher training for workers. This isn’t overkill; it prevents costly mistakes. Anyone who works with this chemical should know its flammability and the pain it can inflict. Splash guards, real training, and respect for personal protective equipment change the odds. Good science, combined with clear communication, cuts down on most risks, turns an unpredictable lab into a safer workspace, and keeps chemical burns out of the headlines.
Anyone who has spent time in a surface science lab knows that modifying surfaces is a mix of chemistry, patience, and a little trial and error. N-Hexadecyltrimethoxysilane, often just called HDTMS, makes a real difference in this field. With its long carbon chain and silane group, it attaches onto inorganic surfaces and leaves behind a hydrophobic coating. I have watched glass become water-repellent and metals resist corrosion after a thoughtful treatment using this compound.
Most teams start by cleaning their surfaces thoroughly. Contamination ruins everything, and HDTMS bonds poorly if oil, dust, or fingerprints get in the way. I usually clean with ethanol or acetone, dry it, and sometimes even expose the surface to a plasma cleaner. Skipping this step leads to patchy, unpredictable coatings—something I learned the hard way.
With the surface ready, HDTMS can be dissolved in an organic solvent like toluene or ethanol. The right concentration depends on the surface and the result you want. I’ve followed protocols where just a small amount—about 1% by weight—delivered amazing changes. Too much HDTMS may actually create a sticky surface, so getting the balance right always matters.
Two big approaches compete for my attention: immersion and vapor deposition. Dipping the material in the HDTMS solution bath works for parts with simple shapes or small sizes. The coating forms as the HDTMS molecules react with surface hydroxyl groups. After immersion, a quick rinse in pure solvent helps remove excess, then a cure in an oven at moderate temperature finishes the job.
On the other hand, vapor deposition helps coat larger or more complex objects. The HDTMS vapor drifts through a chamber, and bonds form directly on the target. This route provides a thin, consistent layer. I get fewer clumps or streaks this way, which is crucial for high-precision applications. Take note—good airflow and control over temperature always play a role, because silanes like HDTMS can react unpredictably with moisture.
Working with HDTMS, you have to stay mindful of health and environmental risks. The fumes irritate eyes and lungs, gloves and fume hoods aren’t optional, and waste needs proper disposal—these steps protect not only the experimenter but also colleagues and the facility itself. Stories about accidents reach every technical conference, so nobody should take shortcuts.
I’ve seen HDTMS used for anti-fogging coatings on safety goggles and self-cleaning glass in modern architecture. The payoff isn’t just a scientific detail; it impacts daily life. Problems still exist—long-term durability under sunlight can be shaky. Teams look at adding UV blockers or modifying the washing and curing steps. These tweaks push performance further, and open up more use cases.
Surface modification works best with well-understood materials and clear procedures. N-Hexadecyltrimethoxysilane rewards thoughtful application and close attention to detail. Taking the time to control each step turns a raw material into a technology that keeps glass clear, metals untarnished, and electronic parts working longer. Proper use means safer, cleaner, and more durable surfaces, not just on lab benches, but out in the world where it matters most.
Lifting the lid on a chemical like N-Hexadecyltrimethoxysilane reminds me of opening a jar in the basement that’s been there longer than you’ve owned your house. Things might look fine, but you never know what’s changed under the surface unless you dig in and pay attention to time, air, and light—the three old enemies of chemical stability.
From my experience, taking shortcuts with shelf life never pays off. Silanes, including this one, break down if ignored. Moisture grabs hold wherever it can. Oxygen starts transformations you don’t even see. Based on most industry reports and first-hand fiddling, you’re looking at about a 12-month shelf life if you keep N-Hexadecyltrimethoxysilane in a cool, dry, sealed container. Pushing it past that date is like rolling dice with your next product batch or R&D experiment.
N-Hexadecyltrimethoxysilane gets touchy with water. The methoxy groups love a good hydrolysis party and will switch to silanol groups if any moisture sneaks in. Once that starts, you’re not getting the same performance. You might catch a whiff of alcohol as the byproduct, or see cloudiness, or notice the all-too-familiar slippery film forming inside your container. These shifts don’t just cause a minor hiccup—they mark the end of what made the silane useful for its proper function, especially if you’re counting on surface modification or durable hydrophobic coatings.
Think heavy-duty zip lock but on an industrial scale: tightly sealed containers, a dry environment, no random heat sources. Manufacturers include desiccants for a reason. I’ve seen more failed batches from forgetting a loose cap than any major handling disaster. A little care avoids a lot of waste, not to mention lost money. Keep the temperature below 25°C and keep those containers closed. Any condensation or drip of water is an invitation for trouble.
A lot of folks in small labs believe a “little exposure” doesn’t change much. Then the silane doesn’t bond, or coatings peel, or test results come out inconsistent. Each failed project points straight back to stability and shelf life. Skipping proper storage threatens more than just one batch—it’s a chain reaction leading to poor performance, safety questions, and sometimes ruined equipment.
Some want to dodge the shelf-life issue by switching to more stable silanes, but trade-offs crop up. Nothing beats simply respecting the chemistry in front of you. If you can’t guarantee the right storage, smaller orders make more sense than bulk buys you can’t use in time. Implementing clear date labeling on storage drums helps, as does regular visual and odor checks. Routine is your best defense against spoiled stock.
This chemical isn’t out to get you, but it rewards those who pay attention. Reliability in any process using this silane starts with one rule: treat it as perishable. Respect shelf life, seal away from moisture, and trust your senses and the calendar. If you do, you keep your work predictable and safe—and gain some peace of mind, too.
| Names | |
| Preferred IUPAC name | hexadecyl(trimethoxy)silane |
| Other names |
Hexadecyltrimethoxysilane Trimethoxyhexadecylsilane n-Hexadecyltrimethoxysilane C16 Silane 1-Hexadecyltrimethoxysilane |
| Pronunciation | /ɛn hɛksəˈdeɪsɪl traɪˌmɛθɒksi saɪˈleɪn/ |
| Identifiers | |
| CAS Number | 16415-12-6 |
| Beilstein Reference | 1698736 |
| ChEBI | CHEBI:85173 |
| ChEMBL | CHEMBL2319111 |
| ChemSpider | 64319 |
| DrugBank | DB11265 |
| ECHA InfoCard | 100.213.245 |
| EC Number | 218-684-2 |
| Gmelin Reference | 71588 |
| KEGG | C19746 |
| MeSH | D017569 |
| PubChem CID | 87777 |
| RTECS number | YU8530000 |
| UNII | 7I4432S21X |
| UN number | UN1993 |
| Properties | |
| Chemical formula | C19H42O3Si |
| Molar mass | 345.62 g/mol |
| Appearance | Colorless to light yellow transparent liquid |
| Odor | Odorless |
| Density | 0.84 g/mL at 25 °C (lit.) |
| Solubility in water | Insoluble |
| log P | 8.8 |
| Vapor pressure | 0.07 mmHg (25 °C) |
| Acidity (pKa) | pKa ≈ 25 |
| Magnetic susceptibility (χ) | `-7.7e-6 cm^3/mol` |
| Refractive index (nD) | 1.424 |
| Viscosity | 1.79 mPa·s (25 °C) |
| Dipole moment | 2.51 D |
| Thermochemistry | |
| Std molar entropy (S⦵298) | 870.6 J·mol⁻¹·K⁻¹ |
| Pharmacology | |
| ATC code | No ATC code |
| Hazards | |
| GHS labelling | GHS07, GHS08 |
| Pictograms | GHS02,GHS07 |
| Signal word | Danger |
| Hazard statements | H315, H319, H411 |
| Precautionary statements | P210, P233, P240, P241, P242, P243, P261, P264, P271, P273, P280, P301+P310, P303+P361+P353, P304+P340, P305+P351+P338, P312, P332+P313, P333+P313, P337+P313, P362+P364, P370+P378, P403+P235, P405, P501 |
| NFPA 704 (fire diamond) | 1-1-0-3 |
| Flash point | 102 °C |
| Autoignition temperature | 220 °C |
| Lethal dose or concentration | LD50 (Oral, Rat): > 2000 mg/kg |
| LD50 (median dose) | LD50 (oral, rat): >2000 mg/kg |
| NIOSH | GV2325000 |
| PEL (Permissible) | Not established |
| REL (Recommended) | 250 mg/m³ |
| IDLH (Immediate danger) | Not Established |
| Related compounds | |
| Related compounds |
Trimethoxy(phenyl)silane Trimethoxy(octyl)silane Triethoxy(octyl)silane Octadecyltrimethoxysilane Hexyltrimethoxysilane Methyltrimethoxysilane |
