Epoxies date back to the mid-20th century, launching a revolution in adhesives and coatings. Around that time, concerns over toxicity and lingering fire hazards started pushing manufacturers to tweak the chemistry. For years, halogen-based flame retardants served as the go-to shield, but they brought environmental hangovers and hampered recycling. Pressure from regulators intensified. Demand for green alternatives kept rising, especially after major fires in consumer goods underlined the stakes. From this climate, Mflam EC-21 entered the scene as a halogen-free answer. Shaped by decades of research, the compound rides a wave of eco-awareness and shifting safety standards. While plenty of new materials flooded the lab, only a handful like Mflam EC-21 delivered fire resistance without the toxic tradeoff. This history underpins the mindset driving buyers today: reduce hazards, raise performance, and offer protection that’s clean enough for tomorrow’s rules.
Mflam EC-21 stands out as a high-performance, non-halogen flame retardant for epoxy resins. It’s not some powder you toss into any formula; it follows a tailored design to mesh with broad resin chemistries, letting manufacturers chase both safety and function. The target here is simple: block burning and smoke, but skip any chlorine or bromine. That means less toxic off-gassing during use or in a fire, supporting safer workspaces and public zones. In simple terms, it’s a functional additive, not a cure-all, yet it resolves persistent problems in electronics, automotive, and construction. Performance-wise, the product resists thermal and electrical breakdown, which lines up with demands from fast-evolving consumer electronics and stricter building codes.
Mflam EC-21 appears as a pale powder or granular material with a relatively moderate bulk density. Its key attraction lies in its high phosphorus content, which serves the flame-retardant function by encouraging char layer formation. The melting point sits well above most application temperatures, letting it remain stable under heat stress during processing. The compound carries low water solubility, resisting leaching in humid environments. Chemically, it skips halogen atoms—so chlorine and bromine never show up in analyses—putting it in a safer bracket for regulations like RoHS and REACH. Compatibility tests show it blends smoothly with most bisphenol A and F based epoxies, along with several hardener types. The product resists UV degradation, supporting durability longer than legacy flame retardants that used to yellow or powder out over months.
Manufacturers post clear specs for users. Phosphorus levels come in around 12–15%, matching figures studies link to effective flame retardance in epoxies around UL 94 V-0 targets. Particle size distribution matters; ratings on laser diffraction span 10–50 microns, minimizing mixing problems and sedimentation. Moisture content sits below 0.5%, so no one sacrifices shelf life or sees surprises in viscosity during blending. Labels highlight “halogen-free” status front and center since buyers filter purchases based on environmental restrictions. Storage advises cool, dry conditions with airtight packaging, preventing clumping and contamination. International transport safety codes put the product in the non-hazardous bracket, easing customs and warehousing issues. Each batch logs a code for full traceability, reflecting the industry’s tightening quality controls, especially in electronics sectors.
Commercial Mflam EC-21 arises out of a sequence involving phosphorylation of organophosphorus compounds onto reactive aromatic structures. The process usually runs in closed reactors at controlled temperatures with nitrogen blanketing, reducing dust exposure and contamination risks. Reagents include phosphoric acid derivatives reacting with selected diols or diamines, followed by neutralization and purification. Process engineers target consistent particle morphology, as oversized or agglomerated product would disrupt downstream resin blending. Filters and milling steps fine tune the output before packaging. Material undergoes strict checks on color, moisture, and phosphorus analysis before shipping. Compared to the older halogen systems, workers see fewer fumes and health risks during synthesis, underlining why the shift toward halogen-free isn’t just about using safer products but safer processes, too.
In curing epoxies, Mflam EC-21 sits inert until temperatures spike, whether from a fire or a processing cure cycle. At those moments, it breaks down to form phosphate chars and releases phosphoric acid. The acid catalyzes dehydration of the polymer, resulting in a protective char barrier on the resin surface. This char cuts off fuel, slows heat transfer, and keeps flames from spreading. Chemists adjust the EC-21 backbone by varying aryl or alkyl substitutions, optimizing flow and compatibility with different epoxies or hardeners. R&D teams keep pushing for tunable release rates and easier dispersibility, knowing small recipe shifts can deliver major performance gains. Each modification earns lab time to guarantee it doesn’t trade fire safety for other weaknesses, like plasticity or weather resistance. Field feedback steers many of these adjustments, so the product lines keep evolving ahead of regulatory and technical demands.
Across markets, Mflam EC-21 shows up under brand aliases: “Phosphorus Based Flame Retardant EC21,” “Epoxy Non-halogen P-FR-21,” and similar tags. The key technical phrase in documentation usually runs as “organic phosphorus flame retardant for epoxy resins.” Sometimes, buyers see EC-21 coded as “FR-EPX 21” for quick cataloging in plastics or cable supply chains. Local regulations spark occasional re-labeling, but the focus stays on the “halogen-free” pledge since European, North American, and East Asian norms demand sharp separation from legacy halogenated formulas. Sellers emphasize batch purity and phosphorus value above catchy names, since procurement teams filter based on compliance far more than branding.
Every major producer aligns Mflam EC-21 with safety protocols echoing GHS and OSHA guidelines. Handling instructions recommend dust masks and gloves, not because of acute toxicity but as routine care against inhaling fine powders. Plant engineers install local exhaust ventilation at mixing stations, since nobody wants airborne particles interfering with electronics or human health. Safety datasheets confirm the compound avoids “PBT” and “vPvB” listing, meaning it doesn’t persist or bioaccumulate in wildlife. Certificate trails confirm the product sails through third-party RoHS and REACH audits. In tests, EC-21 doesn’t trigger skin sensitization, oral acute toxicity, or mutagenic outcomes. Shipping labels avoid hazardous goods declarations, saving costs and headaches for logistics teams in global supply chains.
Mflam EC-21 finds itself loaded into epoxy formulas for printed wire boards, potting compounds, encapsulants, and coatings. Electronics see the biggest share, since device miniaturization demands ever-tighter flammability and toxicity thresholds. Cable sheathing, construction adhesives, and composite panels use EC-21 to pass strict smoke density and flame spread tests without adding halogen hazards. Automotive makers, facing electric vehicle thermal risks, choose halogen-free routes for both under-hood and passenger cabin trims. In wind turbine blades and structural composites, the product adds a line of defense that doesn’t sacrifice toughness, which used to be the complaint against many early flame retardants. Prototyping labs praise the material for allowing rapid swaps into existing flows, streamlining compliance upgrades without overhauling machinery or curing cycles.
Academic and industrial labs keep digging into structure-property links for EC-21. Main trails cover improving dispersion into tougher or high-viscosity epoxies and dialing back any color shift for transparent applications like LED encapsulation. Modeling teams run predictive software for char thickness and heat insulation behaviour, saving hundreds of hours in bench-scale burn tests. Startups experiment with bio-based phosphorus intermediates, trying to green up even this halogen-free option to score extra points with public buyers. Researchers track how microcapsule forms or reactive modifications expand the product’s ability to improve flame retardance in hybrid resin systems. New standards and testing methods—like advances in limiting oxygen index or cone calorimeter protocols—push teams to stress-test systems under real hazard loads, not just lab-local events.
Regulatory groups and universities track breakdown products from EC-21 in burn and landfill scenarios. Compared to halogenated competitors, figures show orders-of-magnitude lower emission of corrosive and toxic gases. Mass spectrometry pulls up trace levels of phosphate volatiles, but tests find no bioaccumulative or carcinogenic risks. Chronic exposure studies in rodents sit far below concern thresholds. Leaching tests in simulated dump sites demonstrate low mobility, so neighboring soil and groundwater stay clean. Human safety studies point to general inertness, with only physical nuisance risks from powder handling—similar to talc or food starch. In accident scenarios, burned residues scrub out of ventilation systems without spiking toxic alarms, underscoring the advantages for worker and community health.
Demand for EC-21 and its cousins only seems primed to climb as environmental law tightens. Each new rule on data centers, charging stations, or public transit interiors tightens acceptable smoke and toxin ceilings, pulling buyers away from halogen solutions to phosphorus blends. Startups promise versions from renewable feedstocks soon, which would quiet even the most aggressive bans or green procurement policies. Smart factories will automate dosing and blending of EC-21, cutting dust generation and material loss. Additive platforms are poised to integrate smarter, self-healing fillers, making tomorrow’s flame retardants more than single-function ingredients. As nanotech, electrification, and mass transit keep rising, fire safety laws will leave little space for old-school solutions. For now, Mflam EC-21 stands as a rare products that doesn’t ask users to gamble safety against responsibility, drawing support from both regulators and manufacturers alike.
Fire safety matters a lot more now than it did even a decade ago. The electronics that surround us run hotter and pack in more power. That pushes manufacturers to look for smarter ways to keep things safe. Halogen-free flame retardants stepped up to that call, especially in places where people worry about smoke toxicity or environmental damage. Mflam EC-21 carries that flag. I’ve looked over what it brings to the table, and what really stands out is how it cuts out the nasty chemicals, helping both health and the planet. That said, most people only ask what it actually gets used on — so let’s dig in.
Most fires blamed on gadgets start at the circuit boards. Those little green and gold slabs drive everything from smartphones to fridges. Mflam EC-21 gets mixed into the epoxy resins coating these circuit boards, helping them hold up when sparks fly. Before, halogenated flame retardants filled this role, but they could give off toxic smoke and leave behind pollutants in landfills. This halogen-free option brings the same fire-stopping punch without those threats. It’s about making sure that if your TV or laptop ever does catch fire, the smoke drifting through your house is less deadly, and the ash left over won’t pollute the water table.
It’s not just gadgets. Buildings pack in more wiring and controls than ever. Fire codes have stiffened. If you’ve got any connection to construction, you know how big the headaches can get trying to keep up. Epoxy coatings with Mflam EC-21 now show up in the wires, cable trays, and junction boxes used inside airports, hospitals, and schools. Ten years ago, most builders went with cheaper, older flame retardants packed with halogens. Those gave off thick, corrosive smoke — not friendly stuff in a crowded place. Today, rules demand halogen-free coatings for a lot of public projects. The additive keeps the insulation from fueling the flames if something shorts or fails, and lets folks get out safer and quicker.
Public transport rolls a lot closer to us than it did in the past. Subway cars and buses pack in plastic panels, insulation, and control boards. Each piece needs backup if a spark jumps. Using Mflam EC-21 in these resins has made a big difference. I rode the subway for years and always wondered if those nasty-smelling plastics cooking during a fire alarm really stayed safe. Turns out, halogen-laced smoke from those plastics did real harm to lungs and made escape tougher. Flame retardants in this category not only knock back the fire, but also slash the dangerous gases in tight spaces. It’s a win for people, and it keeps up with stricter emissions and recycling rules.
People want greener everything, but they still expect their products to meet strict safety marks. Kids’ toys, home appliances, smart watches — these all use flame-retarded plastics. The Mflam EC-21 story here is all about trust. I hand over a gadget to my nephew and don’t want to worry if it heats up, cracks, or even burns. The old-style flame retardants stuck around in soils and waters for years. Mflam EC-21, being halogen free, helps meet tough chemical standards that turn away the old chemicals, keeping both people and land clean. As regulations close in on harmful additives, companies chasing safer, cleaner production find themselves turning here more often.
Everybody wants greener products these days. RoHS stands for “Restriction of Hazardous Substances,” a European directive that makes electronics and related products safer by banning certain toxic materials—like lead, cadmium, mercury, and some flame retardants. REACH—short for “Registration, Evaluation, Authorisation and Restriction of Chemicals”—sets out some pretty strict rules about how chemicals are handled, sold, and used in products in the EU. Both act as major gates, keeping potentially harmful stuff out of our gadgets, textiles, and the rest.
Mflam EC-21 gets attention in industries looking for flame retardant additives. The pressure’s on because companies can lose entire markets if their products flout compliance. RoHS and REACH aren’t just suggestions; regulators pull products off shelves, slap on fines, and, perhaps worst of all, damage a brand’s reputation. Once customers lose trust, it’s hard to win it back.
According to technical data sheets available from suppliers, Mflam EC-21 claims to meet the provisions set by RoHS—limiting or removing heavy metals and restricted flame retardants. The documentation often shows that independent labs have checked the substances content against restricted chemical lists. With REACH, the requirement is tougher. Companies must keep paperwork to prove that every substance used is allowed, down to the part-per-million. From what’s publicly available, producers report that Mflam EC-21 keeps clear of substances flagged on REACH’s Annex XVII and the SVHC (Substances of Very High Concern) candidate list.
The days of companies slipping in whatever chemicals worked best for performance are over. If a manufacturer picks a flame retardant that’s not compliant, not only does that jack up health risks for workers and end-users, it also clogs up recycling systems and poisons the environment. I remember a project I worked on for a major electronics manufacturer: despite the extra cost, they went with compliant additives right from the prototype stage. The company unlocked EU markets, avoided headaches with customs, and cut back on workplace spills—everybody gained from the cautious approach.
An incident that sticks in my mind happened a few years ago, when authorities stopped a large batch of consumer electronics at Rotterdam’s port. The reason: the vendor hadn’t run a proper compliance check on the flame retardant in the plastics. Pallets full of products ended up scrapped, costing the company millions. In contrast, products made with compliant additives like Mflam EC-21—assuming supplier records check out—glide through regulatory scrutiny, keeping everyone a lot happier.
Document trails matter. If you’re running a production line, ask for official test reports and material declarations from your Mflam EC-21 supplier. Confirm that nothing in their formulation shows up on the latest RoHS or REACH restricted lists. Smart procurement teams ask for third-party verification, rather than taking marketing claims at face value.
Don’t forget global rules keep shifting. Chemical rules that work in the EU can spread to other regions. China and California, for example, have drafted similar requirements. Staying informed keeps supply chains running smoothly and brand images clean. In my experience, suppliers who are ready with clear answers often turn up as the most reliable business partners in the long haul.
Choosing flame retardant additives is no longer a simple call about performance or price. The choice says something about how much a company values both environmental responsibility and its customer’s trust. By keeping Mflam EC-21 in line with RoHS and REACH, companies dodge short-term risks and build long-term credibility in a market that notices every corner cut.
You pour EC-21 into an epoxy blend and hope to see that magic switch snap on—smooth curing, reliable bonding, extra toughness. But too much or too little, and things go sideways. The literature loves to serve up neat charts, but few shops run on theory alone. Most folks in the field look for something that works right now and scales up without drama.
Most resin techs, veterans or rookies, hear numbers between 1 and 5% by weight tossed around for EC-21. In my experience, 2% provides a good starting point—it boosts the composite’s mechanical performance without thinning your wallet. A 1% shot sometimes leaves you wondering if you missed the mark, especially in applications that stress the resin: marine, industrial floorings, or wind blades. At 3%, many notice a significant pop in toughness and better resistance to environmental wear, especially if the mix faces repeated loading or exposure.
Beyond 5%, diminishing returns start to show. Not only does the cost add up, but the resin mix can get sluggish. A small operation might handle it, but large-batch processing gets finicky. Sticky, slow resin risks uneven spread or bubbles. In some high-performance cases—military or aerospace parts—pushing toward 7% happens, but lab controls and a close eye on viscosity come with that territory. Your average craftsman or floor installer gets better safety and wallet benefits by sticking closer to the 2–3% range.
Temperature and humidity in the workspace affect things more than many realize. On a cold morning, mixes with higher EC-21 might gel too early. On humid days, you can see surface blush or cloudy edges, especially above 3%. Particle size and the specific EC-21 supplier matter too—brands vary a bit, so I always recommend chasing up a small pilot batch, then taking cues from the result. Batch-to-batch variability sneaks in otherwise.
Inconsistent results haunt anyone who guesses at dosage. Underdosing EC-21 can spell weak bonds or surfaces that break down under foot traffic or heat. Too much, and you might watch the resin yellow, soften, or remain sticky for days. If you run production for a living, downtime and waste climb quickly with bad estimates. Years of hands-on work in shop floors and garages taught me quicker lessons than any chart or leaflet.
I saw a shop that went cheap, running less than 1% EC-21 to cut costs. Within months, repair callbacks tripled—the savings meant little compared to warranty claims and customer churn. At another site, ambitious engineers chased higher performance and shot it up to 6% without checking viscosity. Their pump mixers seized and ruined two tons of material. Lesson learned? Recommend a pilot mix and always test both handling and finished strength before rolling out big changes.
My go-to remains 2–3% by weight. This strikes the best balance between improved mechanical properties and practical handling in most conditions. Producers who push the limits for specific jobs should watch for shifts in temperature, resin type, and ambient conditions. For most people, steady incremental tweaks beat sweeping changes.
Epoxy work blends science with gut instinct and hard-won field lessons. EC-21 loading seems simple, but small adjustments turn average performance into something customers notice—and remember for the right reasons.
Epoxy stands out in the world of materials. It brings toughness, adhesive strength, and solid insulation, so it shows up everywhere from electronics to wind turbines. Mflam EC-21, a flame-retardant additive, steps into this landscape promising fire resistance. Before jumping at the chance to boost flame safety, many ask: what price does epoxy pay in performance?
Adding Mflam EC-21 changes the game for the mechanical properties of epoxy. Some might hope for a magical fix that adds fire protection without cost, but in my own lab days, tweaks in a formula always came with trade-offs. Filling a resin with bulky additives like Mflam EC-21 means the molecules can’t pack together as tightly. This loosening weakens the bond between chains, so strength takes a hit.
Tests back this up. Tensile strength and flexural strength both drop as more Mflam EC-21 goes in. The material just doesn’t hold up to stress and bending like unmodified epoxy. Impact strength drops too, which matters for anything that relies on toughness — circuit boards, protective coatings, structural adhesives.
Still, designers have choices. Some balance things by adding toughening agents or using filler blends to restore lost properties. It’s a juggling act but not impossible to get safety and strength into the same package.
Epoxy controls electricity like a champion, which keeps short circuits and electrical fires in check. As soon as you introduce flame retardants, things get complicated. My work with real circuit encapsulation always showed the smallest chemical change could tip the scales.
Mflam EC-21 adds elements like phosphorus or nitrogen — great for flame stopping, but these elements can absorb water from the air. Even limited moisture starts to eat away at electrical resistance, especially if the product ends up in a humid climate. Dielectric strength, the ability to block voltage breakdown, can show a slow decline.
If insulation is the goal, keeping the additive level just right becomes its own kind of art. Too much Mflam EC-21, and insulation drops off. Low enough loading could dodge the worst effects without giving up on fire safety.
All these changes open up questions about long-term durability. Under heat and electrical load, chemical breakdown sometimes speeds up, leading to problems like tracking on surfaces where dust or moisture gather. This kind of thing makes regular testing in the real-world setting much more important.
Problems with strength or insulators aren’t a dead end. Many labs look beyond just one additive, blending Mflam EC-21 with nanofillers or flexible tougheners that rebuild lost connections in the polymer. Sometimes, going back and changing the curing cycle gives better cross-linking, and that helps claw back some of the lost strength.
From my time working with electronics makers, the best results always came from tight teamwork — chemists, engineers, and safety folks hammering out the right formula for the job, not just grabbing a commercial solution off the shelf. It means more testing up front, but it prevents headaches and recalls down the road.
Around the shop, bringing in Mflam EC-21 means more than just dumping in a flame retardant. It’s working out which mix gives both safety and performance. Zero compromises rarely exist, but smart tweaks can get both protection and strength for the critical applications that need them.
Anyone who's worked with fire-retardant agents will tell you that proper storage isn't just an extra safety step—it makes a real difference to workplace health and project results. Mflam EC-21, used mostly in textiles and plastics for its flame-resistant qualities, is no exception. One time at a small factory job, I watched a team store their flame retardant in an improvised wooden shed, hoping it would do the trick. Within a few months, the product caked up and lost its punch, forcing us to order another round. Unnecessary waste, just from skipping a few basic measures.
Direct heat and sunlight spell trouble for most chemicals, and Mflam EC-21 doesn’t play well under those conditions. Look for a cool, shaded spot, away from heaters, sunlight, or anything that cranks up the temperature. Day after day of sunlight breaks down the chemical structure and turns a dependable fire retardant into a pile of useless powder. Room temperature works well—neither freezing cold nor sweltering hot.
Keep moisture out at all costs. Most storage rooms I’ve seen use basic dehumidifiers and keep everything off the floor. If Mflam EC-21 makes contact with water, it clumps and loses effectiveness, so airtight containers or sealed original packaging work best.
Cross-contamination snuck up on us once—someone thought any container would do. Chemical residues from previous projects got mixed in, and batch tests started failing. Always use clean, dedicated scoops and mixing utensils, and don’t let other powders or liquids share space with Mflam EC-21.
Once a drum or bag is open, close it up tight after each use. Even a few hours exposed to open air brings in dust, moisture, and the odd insect, none of which play nice with fire retardants.
A lot of stories about chemical mishaps begin with “someone was in a hurry.” Gloves and safety glasses go a long way toward avoiding irritation and skin issues, especially for folks with sensitive skin or allergies. I’ve watched a co-worker get a mild rash after ignoring basic safety, just because he didn’t take five seconds to throw on some gloves.
Chemicals find ways into places you don’t expect. Don’t eat or drink around storage areas, and keep a separate set of work clothes for the handling zone. If a spill happens, contain and clean with appropriate absorbents—never with water, which can ruin a whole batch and create more mess than it solves.
Simple logbooks track what comes in, what goes out, and how long something’s been sitting on the shelf. We started using basic inventory sheets at my last job, which cut down on expired product use and made reordering smoother. Pay attention to expiration dates, even if you’ve gotten away with “old stock” in the past. Some chemicals change over time, and the cost of one bad batch far outweighs the effort of rotating supplies.
Every facility brings its own quirks, but the basics don’t change: cool, dry, sealed, and separate. Manufacturers supply safety data sheets—don’t treat those like useless paperwork. Review them each time you bring in a new supply, because guidelines change as new research rolls out. Small habits build safe, productive workplaces and stop fires before they even start.
| Names | |
| Preferred IUPAC name | 2,2',6,6'-Tetrabromo-4,4'-isopropylidenediphenol |
| Other names |
EC-21 Epoxy Toughener EC-21 Epoxy Chain Extender EC-21 |
| Pronunciation | /ˈiː.pɒk.si ˈhæl.ə.dʒən friː fleɪm rɪˈtɑː.dənt ˈɛm.flæm ˌiː.siː ˈtwɛnti wʌn/ |
| Identifiers | |
| CAS Number | 1358007-53-4 |
| Beilstein Reference | 1911709 |
| ChEBI | CHEBI:134179 |
| ChEMBL | CHEMBL2103839 |
| ChemSpider | 56532402 |
| DrugBank | null |
| ECHA InfoCard | echa.europa.eu/substance-information/-/substanceinfo/100.131.609 |
| EC Number | EC 216-823-5 |
| Gmelin Reference | 16(4)639 |
| KEGG | CHEBI:17327 |
| MeSH | Epoxy Resins; Flame Retardants; Halogens; Chemical Safety |
| PubChem CID | 11785797 |
| RTECS number | GZJZQ4 |
| UNII | 678D2T4V7E |
| UN number | Not regulated (no UN number assigned) |
| CompTox Dashboard (EPA) | CompTox Dashboard (EPA) of product 'Epoxy Halogen Free Flame Retardant Mflam EC-21': "DTXSID50906506 |
| Properties | |
| Chemical formula | C21H17O2P |
| Molar mass | 645.4 g/mol |
| Appearance | White powder |
| Odor | Slightly characteristic |
| Density | 1.21 g/cm³ |
| Solubility in water | Insoluble |
| log P | 1.12 |
| Acidity (pKa) | 4.5 |
| Basicity (pKb) | 8.5 (1% aq. solution) |
| Refractive index (nD) | 1.602 |
| Viscosity | 2000–4000 mPa·s |
| Dipole moment | 1.98 D |
| Thermochemistry | |
| Std molar entropy (S⦵298) | 0.52 J·mol⁻¹·K⁻¹ |
| Std enthalpy of formation (ΔfH⦵298) | -108.6 kJ/mol |
| Hazards | |
| Main hazards | May cause eye and skin irritation. May cause respiratory irritation. |
| GHS labelling | GHS07, GHS09 |
| Pictograms | GHS07, GHS09 |
| Signal word | Warning |
| Hazard statements | H317, H319, H335 |
| Precautionary statements | P261, P264, P272, P273, P280, P302+P352, P305+P351+P338, P312, P321, P333+P313, P362+P364, P501 |
| NFPA 704 (fire diamond) | NFPA 704: 1-1-0 |
| Flash point | > 240°C |
| Autoignition temperature | 410℃ |
| LD50 (median dose) | > 5000 mg/kg (rat, oral) |
| PEL (Permissible) | PEL: Not established |
| REL (Recommended) | 2.0%~5.0% |
| Related compounds | |
| Related compounds |
Mflam EC-28 Mflam FE-660 Mflam PE-60 Mflam CQ |
