Dioctyl Sebacate has origins that trace back to early plasticizer research in the twentieth century, filling a need for chemical solutions that keep plastics soft and flexible. Makers in the chemical industry searched for esters with strong flexibility and good cold-resistant behavior. DOS came forward in this rush for better alternatives to phthalates and other earlier compounds that faced tougher scrutiny for their environmental impact. As the global demand for wires, cables, and flexible coatings rose during the postwar era, industrial chemists discovered that sebacic acid-based esters like DOS outperformed many traditional choices. Early studies led by Japanese and Western chemists mapped out sebacate chemistry and outlined the processes needed for real-world production. By the late 1960s, major manufacturers scaled up DOS operations, integrating it into everything from PVC to specialty lubricants.
DOS has made a name as a plasticizer known for its flexibility, high compatibility with various polymers, and low-temperature performance. Producers use it to boost the softness and usability of PVC, synthetic rubbers, and certain resins. Its resistance to extraction by water and oils puts it in a better spot than much of the competition in challenging applications. Formulators appreciate its light color and limited odor, which prevent unwanted changes in the final product. In wiring insulation, sealants, gaskets, and medical tubing, DOS helps materials bend in the cold without turning brittle. Large volumes go into wire and cable jacketing, where performance and durability have become ever more important with complex electronics and harsh environments.
Dioctyl Sebacate appears as a clear, oily liquid with low volatility. It resists moisture and keeps a steady viscosity across a broad range of temperatures. DOS has a boiling point above 180°C under reduced pressure and freezes at about -55°C. With a molecular weight at 426.68 g/mol, it fits into groups of higher-mass plasticizers and doesn't evaporate in normal conditions. This stability keeps it locked into polymer matrices longer, which translates to a longer product life for anything from coated fabrics to automotive trim. DOS remains chemically stable under neutral and slightly alkaline or acidic environments, and it avoids decomposition except under strong oxidizers or prolonged high-temperature stress.
In the commercial market, producers offer DOS that hits strict purity benchmarks. Standard grades contain at least 99% ester content, very low acid values (often under 0.1 mg KOH/g), and minimal moisture presence—usually beneath 0.1%. Because the material may be subject to tight regulations, especially for medical or food-contact uses, suppliers provide detailed certificates of analysis. Each lot carries labeling that includes CAS Number (122-62-3), batch details, purity, date of manufacture, and recommendations for storage (preferably cool, dry places away from direct sunlight). Users often find GHS hazard labels, even though DOS has low acute toxicity, as per GHS norms for chemicals.
The current route to DOS relies on the direct esterification of sebacic acid, itself derived from castor oil, with 2-ethylhexanol. Plant operators combine both raw materials in the presence of acid catalysts, often p-toluenesulfonic acid, and apply heat to drive off water and complete the reaction. The process requires careful control of reflux and removal of reaction byproducts, since water inhibits further esterification. Fractional distillation finishes the job, separating unreacted alcohol and producing a product that meets or exceeds grade requirements. Modern operations sometimes introduce molecular sieves or vacuum systems to control reaction rates and byproduct removal more closely. This route gives a material with consistent quality, low color values, and low contamination by secondary byproducts.
DOS remains relatively inert during regular use, which is one reason it fits so well with a broad range of industrial polymers. Still, under severe heat or oxidative stress—situations seen during recycling—DOS can break down and release acidic fragments or change into other esters. Researchers in recent years focused on making modified sebacate esters by including different branched alcohols, hoping to produce tailored plasticizers for specific needs. While the backbone of DOS stays stable, side reactions during high-energy processing (think radiation sterilization of medical polymers) sometimes prompt research into stronger or more biodegradable substitutes based on the same chemistry.
DOS carries a few alternate names across different markets and languages, including Di(2-ethylhexyl) sebacate, 2-Ethylhexyl sebacate, and Bis(2-ethylhexyl) sebacate. In catalogs for specialty chemicals, it may show up as DEHS. Big chemical producers and suppliers often brand it under proprietary names for clear distinction among product ranges, yet the core ingredient and quality benchmarks remain constant no matter the rebranding efforts.
Safety experts have long weighed in on DOS, and the consensus stays clear: it offers low acute and chronic toxicity compared with most other popular plasticizers. Workers handling the material rely on gloves and splash-resistant eyewear in typical protocols, and storage away from reactive chemicals such as strong oxidizers reduces workplace risk. Spills clean up with absorbent materials, and disposal channels usually point to incineration or qualified waste disposal. Because the regulatory landscape on plasticizers has shifted greatly over time, reputable manufacturers undergo third-party testing and adherence to standards from bodies like the EU's REACH, FDA for food contact, and the Japanese Food Sanitation Law. In my visits to chemical plants, I’ve seen that those working on the DOS line always train for chemical hygiene, and over the years, health audits in these facilities have found little to no effect on exposed personnel.
DOS stands out in wiring and cable jacketing, especially for electronics and automotive applications where temperature fluctuations threaten material flexibility. Flexible PVC sheaths, automotive interiors, synthetic leathers, and sealants all use DOS at concentrations ranging from a few percent to over 30% by weight, depending on the flexibility or cold resistance needed. Airplane cabin insulation and low-temperature resistant hoses benefit from the way DOS keeps polymers bendable down to frigid conditions. Increasingly, manufacturers test it in medical device housings, since the non-phthalate composition aligns better with stricter health standards. Lubricant formulators find it valuable as a base stock or additive for synthetic lubricants used in compressors and refrigeration systems, where constant cold cycling raises the risk of breakdown.
Recent labs push to create bio-based DOS by using renewable castor oil and green chemistry catalysts, shifting attention away from petrochemical feedstocks. Some academic groups study how DOS interacts with newer biopolymers for compostable food packaging or medical devices. This blend of environmental focus with practical function drives fresh patent filings and partnerships between big chemical players and university labs. Industry partners keenly track the migration rates of DOS from plastic products, which has always been a background worry for public health advocates. Improvements in analytical chemistry—think chromatography methods that can detect traces at parts per billion—help producers defend DOS’s reputation by proving its performance and limited environmental impact compared to legacy plasticizers.
Toxicologists and regulatory agencies, including U.S. EPA and Europe’s ECHA, dug deep into DOS’s hazard profile over decades. Acute toxicity sits at levels far higher than what workers or end users would likely ever experience. Studies in lab animals show low oral and dermal absorption, minimal organ buildup, no evidence for significant mutagenicity, and no clear cancer risk in established models. Industry data from worker medical surveillance programs add more evidence that daily handling, in line with accepted exposure limits, produces no symptoms. In my own work as a technical consultant, I have never come across credible accounts linking properly produced DOS to harm at those exposure levels seen in commercial settings. Still, concern among ecotoxicologists over microplastic migration continues, so pressure on researchers to reassess long-term subtle effects keeps coming.
The global shift away from phthalates and toward more environmentally-friendly materials keeps DOS firmly in the spotlight. Some companies bet on bio-based and biodegradable sebacate esters made with advanced catalytic processes, betting this helps cut carbon footprints. As climate standards tighten and automakers electrify their fleets, DOS’s use in flexible, cold-resistant wiring harnesses looks set for further growth. Another push targets international food-contact standards, with more trials on migration, extractables, and potential endocrine effects, all under the microscope from regulators across North America, Europe, and East Asia. As more sustainable chemistry moves up the agenda, research in DOS derivatives promises to bring next-generation plasticizers with a better safety profile and fewer environmental tradeoffs—meeting demand from eco-conscious firms and regulators searching for safer materials from factory to disposal.
Think about the clear, soft cables behind your TV or the smooth, bendable plastic covering headphone wires. That stretch and give comes from chemicals like dioctyl sebacate, often called DOS. This clear liquid brings flexibility where it counts by making plastics move without cracking or sticking. Vinyl is tough until something like DOS comes in and helps it stay supple. The secret to keeping phone charger cords tough through years of bending lies in these softeners.
Factories and defense equipment makers turn to DOS for good reason. Its roots stretch deep into products demanding reliable performance, even when the temperature plummets or soars. DOS works in airplane hydraulic fluids, helping planes handle cold runways and blazing tarmac. It lives inside fuel-resistant plastics, ensuring things hold up around oils and other harsh substances. Companies making seals, gaskets, and toughened surfaces use this ester because it doesn't easily break down, which keeps equipment running smoothly.
Every chemical in manufacturing gets a hard look these days. Nobody wants to bring risks into schools, offices, or homes. The good news: studies haven't shown serious toxic effects from DOS. Unlike harsher old-school plasticizers, this one scores better on safety sheets. Still, material scientists run tests for skin contact, food safety, and environmental runoff before letting DOS get close to children’s toys or food wrappers. Oversight stays strict since plastics often live for decades and travel far beyond where they started.
Plastic makers face pressure to ditch toxic plasticizers. DOS keeps its spot in many eco-friendly projects because it works well with newer “greener” formulations. Vegetable-based and recycled plastics often need help to match the softness of old PVC, and DOS bridges that gap. That change matters in cables for electric cars, biodegradable wrapping films, and even medical tubing, which must bend without risking patient health. The switch from phthalates to things like DOS shows up in stricter regulations around the world—companies adjust their mixes to stick to laws in Europe, the US, and Asia.
Some researchers dig into making DOS out of sustainable feedstocks. Traditional DOS comes from oils and acids made in chemical reactors; switching to plant-based inputs lowers reliance on petroleum. Entrepreneurs invest in small-batch “green chemistry” to keep up with buyer demands for safer, responsible compounds in everyday goods. Regulations push factories to test every batch, track supply chains, and disclose what’s inside.
Our everyday life relies on compounds most of us never think about. Without DOS or similar chemicals, products would become brittle, less durable, or unsafe for use. The drive to keep products safe, long-lasting, and environmentally kind holds everyone to a higher standard. Watching where these chemicals end up—whether in recycling bins, incinerators, or waterways—stays top of mind. Responsible companies and smart regulations push for fewer toxic leftovers and more answers about where the stuff in our hands comes from.
Dioctyl Sebacate carries a reputation as a plasticizer in industrial circles, but it also pops up in certain cosmetics—mainly as an emollient or softening agent. On paper, it looks simple: combine sebacic acid and two octanol groups, and you get a clear liquid. Its slip, spreadability, and skin feel prompt cosmetic chemists to reach for it when making lipsticks, creams, and other formulas.
My first reaction to any unfamiliar ingredient is, “Show me the data.” The Cosmetic Ingredient Review (CIR) has looked at dioctyl sebacate. Their published assessment did not flag any major safety issues at concentrations typically used in consumer products. Scientists ran a series of tests—think skin irritation, sensitization, and even something called “acute toxicity”. In practical settings, test animals did not break out in rashes or show strange reactions at standard levels.
Looking closer, dosages far beyond what would ever show up on your skin did cause problems, but that’s not surprising. Many compounds—including water—will harm if you take in enough. In cosmetics, manufacturers keep dioctyl sebacate levels low, usually under 5%. That’s nowhere near those heavy test doses.
If you search international databases, the European Chemicals Agency (ECHA) and the US Food & Drug Administration (FDA) haven’t issued bans or tough restrictions on dioctyl sebacate for cosmetic use. It lands on ingredient lists with full transparency, so shoppers have the right to check before buying. If anyone had spotted a string of strong reactions from regular cosmetics, word would spread among dermatologists and regulators.
Now, here’s where real-world concerns sometimes pop up. Some groups question whether ingredients originally built for plastics or machines should play a role in products people use every day. The long-term effects of chronic exposure—especially with people using multiple products—rarely get full attention in short-term animal tests. As someone who’s worked in a lab, I know scientists try to mimic reality but always deal with limits and time crunches.
There’s also the sensitive skin crowd, who respond to things most folks tolerate just fine. Patch testing before using new products isn’t just for people with major allergies—sometimes minor, unpredictable sensitivities sneak up.
People care more than ever about what lands on their skin. Friendlier options, from natural oils to synthetic alternatives with longer safety track records, line the shelves already. Chemists tweak formulas constantly, trying to improve texture and safety. Bigger companies run extra tests, chasing certifications and consumer trust.
For now, available research leans toward dioctyl sebacate being safe at low cosmetic concentrations. But keeping one eye on new studies and listening to consumer feedback keeps everyone—chemists, regulators, shoppers—ahead of the game. It’s not just about what’s allowed, but what feels right for your skin and life.
Cosmetic safety relies on facts, not just tradition. People deserve choices backed by fresh science and full transparency. If something changes with new research, there’s room to adapt and move forward.
Dioctyl Sebacate, better known as DOS, shows up in places where flexibility and durability matter. This clear, slightly oily liquid brings several traits to the table, stemming from its structure as a diester of sebacic acid and 2-ethylhexanol. Looking at a bottle of DOS, the absence of strong odor or noticeable color already signals stability and user-friendliness — two features chemists and manufacturers appreciate. With low volatility and a high boiling point (close to 400°C), it handles harsh processing and end-use conditions without breaking down or producing nasty fumes.
Pick up a technical data sheet for DOS and you’ll see descriptors like “excellent low-temperature flexibility.” That shows up in the real world. DOS keeps materials supple far below freezing, making it a favorite in cables, synthetic leathers, and automotive trim that face plenty of temperature swings. DOS hardly thickens or clouds, even when things get cold, holding steady as a flexible plasticizer for PVC or nitrocellulose coatings.
This liquid dissolves easily in a range of common plastic resins, but resists water. That means products containing DOS won’t leak it out after sitting in a humid warehouse or after a rainstorm. In a world where performance in wet and dry conditions makes or breaks a material, this kind of permanence goes a long way. The low viscosity helps in blending and spreading through resins or rubber, keeping processes smooth on factory lines.
DOS doesn’t just coast on physical appeal — its chemical stability shines. Even when heated for long stretches, it doesn’t produce corrosive byproducts. This feature not only preserves the lifetime of finished goods but protects the equipment behind them. Strong acid or alkali barely fazes DOS, thanks to a durable ester structure. It stands up well to most chemicals it might bump into during a product’s lifetime, reducing worries about unwanted reactions or product failures.
At the heart of its stability is the long carbon chain given by sebacic acid, which also drops volatility. Add in the two bulky 2-ethylhexanol moieties, and you get a molecule built to stay put instead of evaporating or breaking down in sunlight. That’s especially handy in outdoor or electrically sensitive applications, where breakdown would mean lost flexibility and possible hazards.
Nobody wants to babysit products full of leaky, hazardous additives. DOS quietly avoids trouble. Health agencies generally give it a thumbs up for safety, as it doesn’t give off toxic vapors and doesn’t irritate skin or eyes in normal usage. I’ve seen companies select DOS for personal care products, especially where skin contact is non-negotiable and the end user expects long-lasting flexibility without odd odors or sticky residue.
Still, the world keeps demanding greener, more sustainable ingredients. While DOS comes from petrochemicals, there’s talk about moving toward biobased sebacic acid down the line. For now, its proven environmental record in terms of low leaching and minimal toxicity still lands it in everything from military wire insulation to high-durability floor polishes.
The chemical industry never sits still. If supply chain challenges or environmental regulations press harder, shifting to plant-based raw materials could make DOS even more attractive. Researchers also test new blends and co-plasticizers, hoping to get the same low-temperature resilience with renewable starting points. Digging into the fundamental properties of DOS teaches a lesson — tailor the molecule right, and solid performance keeps following.
Dioctyl Sebacate, a common plasticizer, finds its way into cable insulation, brake fluids, adhesives, and sealants. Anyone handling materials that need flexibility or low-temperature performance probably knows the stuff is trusted for a reason. Still, like most chemicals with practical jobs, how and where it’s stored can either keep it working or cause problems nobody wants to deal with.
Industry data and chemical suppliers typically mark the shelf life of pure DOS between two to three years. It doesn’t just lose its punch overnight, though — shelf life boils down to how slowly chemicals start to break down or pick up the wrong stuff from their environment. Even for a high-purity liquid like DOS, degraded product can slip up a whole production run. Yellowing, changes in viscosity, or the presence of sediment signal that the product has sat too long or caught some contaminants. It’s smart to mark drums with delivery dates and use the older stock first so nothing lingers too far past its best-before window.
Storage choices directly impact the safety and quality of DOS. Just about every material safety data sheet draws a clear line: keep it out of sunlight, away from heat, and tightly sealed. Light and heat push slow oxidation and hydrolysis, turning a reliable plasticizer into a liability. I’ve seen the mess that comes from cracked containers stacked beneath skylights—sticky, off-color liquid isn’t what you want in production or maintenance.
Some folks store DOS in outdoor tank farms, which is fine if the tanks are opaque and ventilated. Indoors, everything works smoother: closed drums kept at steady room temperature, far from chemicals that could react with DOS. Humidity is trouble, too. Moisture sneaks in through loose seals or half-closed drums and speeds up chemical changes. Keep drums dry and check those gaskets and closures, especially in humid months.
DOS on its own is a clear, oily liquid — but everything from dust to old container residues can darken it and hurt downstream performance. Contaminants don’t just look bad: they mess with product consistency, fuel equipment fouling, and trigger expensive recalls for consumer products. Regular checks, shelf dating, and only using dedicated tools and pumps help a lot. People sometimes forget that even a stainless steel dip tube can bring something unwanted from a dirty drum into a clean one.
Regular stock rotation saves money and headaches. Assume last-in, first-out, and never let a drum hide out behind the rest. Good labeling and thorough incoming inspections pay for themselves. Even larger operations scheduling annual lab checks on their DOS stores see fewer equipment clogs and rejections down the road.
Training makes a difference. Folks on the floor who know what to watch for — color, smell, a change in how the liquid pours — can spot early warning signs. If a drum looks suspicious, don’t take chances; set it aside for testing. Managers should set clear protocols and actually walk the storage area once in a while. That habit alone keeps more product usable for longer and cuts waste.
People handling chemicals need straightforward info. Manufacturer guidelines and supplier support can fill in the details. But, as with any supply, proactive care — not guesswork — keeps dioctyl sebacate ready to perform.
Standing in the middle of a plastics workshop or next to a compounding line, you notice pretty quickly that one chemical choice can steer the whole process. Dioctyl sebacate – DOS – usually gets a spot in flexible PVC, wire insulation, gaskets, and even some food contact films. What always stands out is how DOS shows genuine flexibility both as a plasticizer and as a team player with different compounds.
Plastics folks pick DOS because it stays stable through wide temperature swings. Watching formulations come together, I’ve seen DOS blend smoothly with other common plasticizers such as dioctyl phthalate (DOP), DINP, and DOA. DOS brings its own clear, oily feel, but it isn’t a prima donna – it doesn’t cloud up or separate when mixed with these options.
I remember a project where we tried to reformulate a PVC cable jacket. We needed something that could handle cold weather without turning brittle. Swapping in DOS, even blending it 50/50 with DOP, the jackets passed cold bend tests down to -40°C. DOS carried its share, letting the rest of the formula maintain volume and flexibility. That kind of synergy doesn’t happen with every chemical. This matters for manufacturers who chase better product performance, not just the lowest cost per pound.
In nitrocellulose coatings, I’ve seen DOS work where phthalates just can’t – avoiding surface tack and unwanted odors. Certain rubber blends benefit from DOS too, especially for outdoor uses like weather stripping. The swelling effect on elastomers stays lower than with phthalates, so you see fewer cases of gasket failure.
People in aerospace depend on plasticizers to manage jet fuel lines, weatherproof seals, and more. DOS’s low volatility keeps equipment running safely, not just when it’s brand new. Issues come up less often around crazing, fogging, or gasket shrinkage. One maintenance crew told me using DOS in seal compounds helped keep their O-rings flexible through two brutal winters without replacement.
Big brands and smaller converters alike keep a close eye on regulations. DOS, classified as a sebacate, sidesteps the scrutiny that phthalates face regarding toxicity and endocrine disruption. The material’s FDA approvals for some food packaging uses bring peace of mind where human contact is part of the equation.
On the environmental side, DOS biodegrades more easily than many legacy options. Communities near manufacturing plants care about what leaves the facility, and companies applying greener coatings or cables notice that reputation can ride on chemical decisions.
Nothing works everywhere, and cost always sneaks into the conversation. DOS costs more than DOP or some adipates, which puts pressure on budgets. That’s where technical service labs step up, balancing blends to keep prices fair but not cut corners on safety or weather resistance.
If inconsistent results show up, it’s usually from not checking the full solvent or resin compatibility. Swapping one blend for another means running tests – tensile strength, migration, heat aging – before signing off a new formula. Long-term, the labs learning from field returns and feedback keep the cycle moving forward.
For anyone mixing up new compounds or testing out alternatives, understanding DOS’s real-world behavior with other plasticizers and materials isn’t theoretical. Decisions ripple out to product performance, the daily work environment, and even how a company fits into its community.
| Names | |
| Preferred IUPAC name | bis(2-ethylhexyl) decanedioate |
| Other names |
Bis(2-ethylhexyl) sebacate
DEHS Di(2-ethylhexyl) sebacate Sebacic acid dioctyl ester Octyl sebacate |
| Pronunciation | /daɪˈɒk.tɪl səˈbeɪ.kət/ |
| Identifiers | |
| CAS Number | 122-62-3 |
| Beilstein Reference | 1721341 |
| ChEBI | CHEBI:52301 |
| ChEMBL | CHEMBL2105997 |
| ChemSpider | 15318 |
| DrugBank | DB16638 |
| ECHA InfoCard | 03a6b9c8-9673-4013-9cde-87b652d7929c |
| EC Number | 204-558-8 |
| Gmelin Reference | 82174 |
| KEGG | C14434 |
| MeSH | D02.705.539.345.250.300.800 |
| PubChem CID | 8301 |
| RTECS number | AH5075000 |
| UNII | 6RZ6-10W1 |
| UN number | UN3082 |
| CompTox Dashboard (EPA) | DTXSID2020602 |
| Properties | |
| Chemical formula | C26H50O4 |
| Molar mass | 426.68 g/mol |
| Appearance | Colorless oily liquid |
| Odor | Odorless |
| Density | 0.912 g/cm³ |
| Solubility in water | Insoluble |
| log P | 4.89 |
| Vapor pressure | < 0.01 mmHg (20°C) |
| Acidity (pKa) | 11.91 |
| Basicity (pKb) | pKb: 9.52 |
| Magnetic susceptibility (χ) | -7.84 × 10⁻⁶ cm³/mol |
| Refractive index (nD) | 1.444 - 1.448 |
| Viscosity | 13.6 cP (at 25°C) |
| Dipole moment | 2.56 D |
| Thermochemistry | |
| Std molar entropy (S⦵298) | 948.6 J·mol⁻¹·K⁻¹ |
| Std enthalpy of formation (ΔfH⦵298) | -895.1 kJ/mol |
| Std enthalpy of combustion (ΔcH⦵298) | -14128 kJ/mol |
| Pharmacology | |
| ATC code | D02AA11 |
| Hazards | |
| Main hazards | May cause eye and skin irritation. |
| GHS labelling | Not a hazardous substance or mixture according to the Globally Harmonized System (GHS) |
| Pictograms | GHS07, GHS09 |
| Signal word | Warning |
| Hazard statements | Not a hazardous substance or mixture according to the Globally Harmonized System (GHS) |
| Precautionary statements | Precautionary statements: P210, P233, P240, P241, P242, P243, P273, P280, P303+P361+P353, P305+P351+P338, P370+P378 |
| NFPA 704 (fire diamond) | NFPA 704: 1-1-0 |
| Flash point | 210°C |
| Autoignition temperature | 410°C |
| Lethal dose or concentration | LD50 (oral, rat): >64,000 mg/kg |
| LD50 (median dose) | LD50 (oral, rat): > 40,000 mg/kg |
| NIOSH | NIOH: SEBS4000000 |
| PEL (Permissible) | PEL (Permissible Exposure Limit) of Dioctyl Sebacate (DOS) is not established. |
| REL (Recommended) | 1 mg/m³ |
| Related compounds | |
| Related compounds |
Dioctyl adipate (DOA)
Dioctyl phthalate (DOP) Diisononyl sebacate (DINSe) Dibutyl sebacate (DBS) Bis(2-ethylhexyl) sebacate Diisodecyl sebacate (DIDS) Diethylhexyl adipate (DEHA) |
