TDI (TOLUENE DIISOCYANATE) T80/20

At the molecular level, TDI (Toluene Diisocyanate) T80/20 has the chemical formula C9H6N2O2 (CH3-C6H3(NCO)2), a low molecular weight of 174.16 g/mol, an exact isocyanate equivalent weight of 87.08 g/eq, a strict difunctionality of f = 2.00, and the highest weight percentage of reactive isocyanate groups (-N=C=O, 48.23% w/w theoretical) of any major commercial aromatic diisocyanate—nearly 53% higher NCO density per kilogram than diphenylmethane diisocyanate (MDI, MW 250.25 g/mol, 33.6% w/w NCO)! Because TDI (Toluene Diisocyanate) T80/20 consists of an precisely controlled 80.0 +/- 1.0% weight ratio of the asymmetric 2,4-toluene diisocyanate isomer and 20.0 +/- 1.0% of the symmetric 2,6-toluene diisocyanate isomer, it provides a built-in regioselective kinetic gradient between its fast-reacting sterically unhindered para-NCO group (at C-4) and its slower-reacting methyl-hindered ortho-NCO groups (at C-2 and C-6)!
During continuous flexible slabstock or molded polyurethane foam production, this 80:20 isomer ratio of TDI (Toluene Diisocyanate) T80/20 is essential for achieving a synchronized blow-to-gel reaction balance. In the first 10 to 40 seconds after mixing with polyether or polyester polyols and water, the highly reactive C-4 para-isocyanate groups of the 2,4-TDI isomer react rapidly with water (generating carbon dioxide gas and primary amines that immediately form linear polyurea hard segments) and primary/secondary polyol hydroxyls to build rising foam viscosity, while the sterically hindered C-2 and C-6 ortho-isocyanate groups of both the 2,4-TDI and 2,6-TDI isomers complete network crosslinking as the internal bun exotherm reaches 110 to 160 °C—yielding open-cell, breathable flexible foams with zero collapse and superior tensile and tear strength.

Beyond flexible bedding, furniture upholstery, carpet underlay, and automotive acoustic/seating foams, TDI (Toluene Diisocyanate) T80/20 is widely reacted with polyether or polyester diols/triols and trimethylolpropane (TMP) to manufacture NCO-terminated cast elastomer prepolymers, moisture-curing polyurethane wood/floor coatings, two-component aromatic polyisocyanate curing agents (such as TDI-TMP adducts and TDI-isocyanurate trimers), flexible packaging laminating adhesives, and elastomeric construction sealants. Partnering with Ataman Kimya for drum, IBC, or temperature-controlled ISO-tank shipments of TDI (Toluene Diisocyanate) T80/20 guarantees strict isomer ratio precision (80.0 +/- 1.0% 2,4-TDI), ultra-low hydrolyzable chlorine (<= 0.005% to 0.010%), and UN 2078 ADR/IMDG hazardous-material logistics expertise.

CAS Number: 26471-62-5 (Benzene, 1,3-diisocyanatomethyl-; Toluene diisocyanate mixed isomers); composed of 80% w/w CAS 584-84-9 (2,4-Diisocyanato-1-methylbenzene / 2,4-Toluene diisocyanate / 2,4-TDI) and 20% w/w CAS 91-08-7 (2,6-Diisocyanato-1-methylbenzene / 2,6-Toluene diisocyanate / 2,6-TDI)
EC Number: 247-722-4 (EINECS for CAS 26471-62-5 mixed isomers), composed of EC 209-544-5 (2,4-TDI) and EC 202-039-0 (2,6-TDI); EU Index No. 615-006-00-4
Molecular Formula: C9H6N2O2 (Condensed Structural Formula: CH3-C6H3(NCO)2; Theoretical Elemental Composition: 62.07% C, 3.47% H, 16.09% N, 18.37% O by weight; Theoretical Isocyanate -NCO Content: 48.23% w/w)

Molecular Weight: 174.16 g/mol (Exact Monoisotopic Mass: 174.0429 g/mol; Isocyanate Equivalent Weight: 87.08 g/eq; Functionality: f = 2.00)
INCI Name: Not assigned (Strictly a reactive industrial monomer and chemical intermediate for polyurethane foams, elastomers, coatings, adhesives, and sealants; prohibited in cosmetics under EU Regulation (EC) No 1223/2009 Annex II)
E Number: Not assigned (Industrial reactive monomer; not a food additive, though fully cured polyurethane resins and laminating adhesives derived from TDI are regulated for indirect food-contact packaging under US FDA 21 CFR 175.105 and 21 CFR 177.1680 subject to zero residual free monomer migration)
Melting Point: 11.5 to 14.0 °C (52.7 to 57.2 °F; Freezing / Crystallization Onset Point of the 80:20 isomer mixture is typically 13.0 to 13.8 °C; pure 2,4-TDI melts at 21.8 °C and pure 2,6-TDI melts at 18.3 °C—cooling TDI 80/20 below +15 °C causes selective crystallization of the 2,4-TDI isomer!)
Boiling Point: 251.0 °C (483.8 °F) at 101.3 kPa (760 mmHg) atmospheric pressure (120.0 °C at 10 mmHg / 13.3 hPa; 115.0 to 118.0 °C at 10 mbar); Pensky-Martens Closed-Cup Flash Point: 127.0 °C (260.6 °F, ASTM D93 / ISO 2719); Cleveland Open-Cup Flash Point: 135.0 °C (275.0 °F, ASTM D92); Autoignition Temperature: > 600.0 °C (~620 °C per DIN 51794); Lower/Upper Explosive Limits in Air: LEL 0.9% v/v, UEL 9.5% v/v
Viscosity: 2.8 to 3.2 mPa·s (cP) dynamic viscosity at 20 °C and 2.2 to 2.5 mPa·s (cP) at 25 °C (kinematic viscosity ~2.0 to 2.5 mm2/s [cSt] at 20–25 °C, flowing nearly as easily as water)
Density: 1.220 g/cm3 at 20 °C and 1.214 to 1.218 g/cm3 at 25 °C (per ASTM D4052 / ISO 12185; Bulk Weight ~10.18 lb/gal at 20 °C; Vapor Density: 6.0 [Air = 1.0]; Vapor Pressure: 0.015 to 0.030 hPa [~0.011 to 0.023 mmHg] at 20–25 °C; Refractive Index n20/D: 1.5670 to 1.5690, n25/D: 1.5654 to 1.5666)

Most Frequently Encountered Synonyms:
TDI (Toluene Diisocyanate) T80/20
TDI (TOLUENE DIISOCYANATE) T80/20
Toluene Diisocyanate 80/20
Toluene diisocyanate T80/20
TDI 80/20
TDI T80
Desmodur T 80
Lupranate T 80
Voranate T-80
Wannate TDI-80
Scuranate T80
Cosmonate T-80
Coronates T-80
Toluen diizosiyanat 80/20 (Turkish)
Toluen diizosiyanat T80/20 (TDI)

WHAT IS TDI (TOLUENE DIISOCYANATE) T80/20?

TDI (Toluene Diisocyanate) T80/20 is an industrial-grade monomeric aromatic diisocyanate consisting of an 80:20 weight-by-weight isomer mixture of 2,4-toluene diisocyanate (CAS 584-84-9, 80.0 +/- 1.0%) and 2,6-toluene diisocyanate (CAS 91-08-7, 20.0 +/- 1.0%). Together with Diphenylmethane Diisocyanate (MDI), TDI (Toluene Diisocyanate) T80/20 is one of the two primary isocyanate pillars of the global polyurethane industry—specifically dominating the manufacture of flexible polyurethane slabstock foam (mattresses, sofas, furniture cushioning, carpet underlay, acoustic sponges), hot- and cold-cure automotive molded seating, and low-free-monomer urethane prepolymers for coatings, adhesives, sealants, and cast elastomers (CASE).
Structurally, each molecule of TDI (Toluene Diisocyanate) T80/20 features a single six-membered aromatic benzene ring substituted with one electron-donating methyl group (-CH3 at ring position C-1) and two strongly electrophilic, cumulene-type isocyanate groups (-N=C=O) positioned meta to each other on the aromatic ring (at positions C-2 and C-4 in the 80% isomer, and at positions C-2 and C-6 in the 20% isomer). Because the aromatic benzene ring withdraws electron density from the nitrogen atom of the -N=C=O group through pi-conjugation, the central carbon atom of each isocyanate group carries a strong partial positive charge (delta+), making TDI (Toluene Diisocyanate) T80/20 orders of magnitude more reactive toward nucleophilic active-hydrogen compounds—such as polyether/polyester polyol hydroxyls (-OH), water (H2O), primary/secondary amines (-NH2 / -NHR), and carboxylic acids (-COOH)—than aliphatic diisocyanates like HDI or IPDI.

Among the three commercially manufactured grades of Toluene Diisocyanate—namely TDI 80/20 (80% 2,4-isomer : 20% 2,6-isomer), TDI 65/35 (65% 2,4-isomer : 35% 2,6-isomer), and Pure 2,4-TDI (TDI 100, >= 99% 2,4-isomer)—TDI (Toluene Diisocyanate) T80/20 accounts for more than 95% of global TDI production and consumption because the 80:20 isomer ratio corresponds directly to the natural regioselectivity of the industrial toluene dinitration process and provides the ideal balance of initial chain-extension speed and final network cure in flexible polyurethane foams.

HISTORICAL DEVELOPMENT AND INDUSTRIAL SIGNIFICANCE OF TDI (TOLUENE DIISOCYANATE) T80/20

Following Otto Bayer's pioneering discovery of the diisocyanate polyaddition reaction in Leverkusen in 1937, Toluene Diisocyanate became the first aromatic diisocyanate scaled up for commercial flexible polyurethane foam manufacture in the early 1950s. Early one-shot flexible foam machines combined TDI (Toluene Diisocyanate) T80/20 first with polyester polyols and subsequently (from 1957 onward) with propylene-oxide/ethylene-oxide polyether triols, water, organotin catalysts (stannous octoate), and silicone-polyether surfactants—revolutionizing global bedding, furniture, and automotive seating by replacing heavy steel coil springs and natural latex rubber with lightweight, breathable, custom-density polyurethane cushioning.
In parallel, polymer chemists discovered that reacting a 2:1 molar ratio of TDI (Toluene Diisocyanate) T80/20 with polytetramethylene ether glycol (PTMEG), polypropylene glycol (PPG), or adipate polyester diols yielded NCO-terminated prepolymers that, when chain-extended with aromatic diamines such as MOCA (4,4'-methylenebis(2-chloroaniline)) or Ethacure 300 (DMTDA), produced ultra-tough cast polyurethane elastomers for industrial wheels, mining screens, and hydraulic seals. Today, global production of TDI (Toluene Diisocyanate) T80/20 exceeds 2.8 million metric tons per year, regulated under rigorous workplace hygiene and closed-loop stewardship standards coordinated by the International Isocyanate Institute (III).

CHEMICAL STRUCTURE, REGIOSELECTIVE REACTIVITY OF 2,4-TDI VERSUS 2,6-TDI, AND POLYURETHANE REACTION KINETICS

Understanding the asymmetric reactivity of the two isomers inside TDI (Toluene Diisocyanate) T80/20 is the key to mastering flexible polyurethane foam and prepolymer formulation:

The Regioselective Steric and Electronic Effect in 2,4-TDI (80% of T80/20) and 2,6-TDI (20% of T80/20):
- In 2,4-Toluene Diisocyanate (80% w/w): One isocyanate group is located at the para position (C-4) relative to the C-1 methyl group, completely free of steric crowding, whereas the second isocyanate group is located at the ortho position (C-2), directly adjacent to the bulky C-1 methyl group. Furthermore, before the first reaction occurs, each electron-withdrawing -NCO group activates the other -NCO group on the same benzene ring; once the unhindered para-NCO group at C-4 reacts with an alcohol (-OH) to form a urethane group (-NH-COO-R), that urethane group has a much weaker electron-withdrawing effect, deactivating the remaining ortho-NCO group at C-2! Consequently, at 25 °C, the C-4 para-NCO group of 2,4-TDI is approximately 4 to 8 times more reactive toward hydroxyl groups than the C-2 ortho-NCO group!
- In 2,6-Toluene Diisocyanate (20% w/w): Both isocyanate groups are located at the ortho positions (C-2 and C-6) flanking the central C-1 methyl group. While both ortho-NCO groups have equal initial reactivity (about half that of the C-4 group of 2,4-TDI), once the first ortho-NCO group reacts, steric crowding and electronic deactivation reduce the reactivity of the second ortho-NCO group by a factor of ~6 at ambient temperature—requiring thermal activation above 80 to 120 °C to react completely.

 Why the 80:20 Ratio of TDI (Toluene Diisocyanate) T80/20 Is Ideal for Flexible Foams and Prepolymers:
- In Flexible Slabstock Foaming: During the first 30 seconds after mixhead pouring, the fast C-4 para-NCO groups of TDI (Toluene Diisocyanate) T80/20 react rapidly with water and polyol OH groups to build linear chain viscosity that traps evolving CO2 gas bubbles without prematurely crosslinking and rupturing the expanding cell walls. Then, as the exothermic reaction heats the rising foam bun to 120–160 °C, the steric barrier of the ortho-NCO groups is overcome, and the 20% symmetric 2,6-TDI isomer forms linear, tightly packed crystalline polyurea hard-segment domains that give the foam high load-bearing hardness (ILD/CLD) and prevent foam recession ("settling").
- In Prepolymer Synthesis (CASE Applications): When preparing an NCO-terminated prepolymer by reacting TDI (Toluene Diisocyanate) T80/20 with a diol or triol (such as TMP or PPG) at 60 to 80 °C, the fast para-NCO group of 2,4-TDI reacts selectively with the polyol OH groups first, leaving the slower ortho-NCO group at the ends of the prepolymer chains and minimizing unwanted molecular weight broadening or high-viscosity oligomer formation!

 The Four Fundamental Reactions of TDI (Toluene Diisocyanate) T80/20 in Polyurethane Processing:
- Reaction A — Urethane Formation (Gelling Reaction, catalyzed by organotin catalysts such as Stannous Octoate T-9 or DBTDL):
  R-N=C=O (TDI) + R'-OH (Polyol)  --->  R-NH-C(=O)-O-R' (Urethane Linkage, delta H ~ -100 kJ/mol NCO)
- Reaction B — Water Blowing & Polyurea Hard-Segment Formation (catalyzed by tertiary amines such as BDMAEE and TEDA):
  Step 1: R-N=C=O (TDI) + H2O  --->  [R-NH-COOH (Unstable Carbamic Acid)]  --->  R-NH2 (Primary Aromatic Amine) + CO2 (Blowing Gas)
  Step 2: R-NH2 + R-N=C=O (TDI)  --->  R-NH-C(=O)-NH-R (Disubstituted Polyurea Hard Segment; total delta H ~ -195 kJ/mol H2O)
- Reaction C — Allophanate and Biuret Secondary Crosslinking (above 110–140 °C at Isocyanate Index > 100):
  Excess NCO groups of TDI (Toluene Diisocyanate) T80/20 react with the -NH- protons of urethane links to form branching Allophanate crosslinks, and with the -NH- protons of urea links to form branching Biuret crosslinks during foam curing.
- Reaction D — Self-Addition Dimerization (Uretdione) and Trimerization (Isocyanurate):
  Catalyzed by phosphines or pyridine, 2,4-TDI dimerizes reversibly into solid uretdione (Dimeric Toluene-2,4-Diisocyanate); catalyzed by alkali carboxylates or Mannich bases, TDI trimerizes into six-membered Isocyanurate rings used in fast-drying 2K polyurethane wood coatings.

INDUSTRIAL PRODUCTION AND MANUFACTURING PROCESSES

Commercial TDI (Toluene Diisocyanate) T80/20 is manufactured on a massive world-scale continuous basis via a four-step integrated chemical synthesis starting from petrochemical toluene:

Stage 1 (Two-Stage Regioselective Dinitration of Toluene to Dinitrotoluene DNT 80/20):
  Purified toluene (methylbenzene) is nitrated with mixed nitric and sulfuric acid (HNO3 / H2SO4). In the first stage, mononitration yields ortho-nitrotoluene (~58%), para-nitrotoluene (~38%), and meta-nitrotoluene (~4%). After removing the minor meta-isomer, second-stage nitration of the ortho-/para-nitrotoluene mixture naturally generates an ~80:20 isomer mixture of 2,4-dinitrotoluene (2,4-DNT, ~80%) and 2,6-dinitrotoluene (2,6-DNT, ~20%)—which directly establishes the 80:20 isomer ratio of finished TDI (Toluene Diisocyanate) T80/20!

Stage 2 (Catalytic Hydrogenation of DNT 80/20 to Toluene Diamine TDA 80/20):
  Molten DNT 80/20 is hydrogenated continuously with hydrogen gas (H2) at 120 to 180 °C and 20 to 40 bar over a supported Raney nickel or palladium-on-carbon (Pd/C) catalyst, followed by distillation to remove reaction water and trace ortho-diamine isomers (2,3-TDA and 3,4-TDA), yielding >= 99.5% pure meta-Toluene Diamine (m-TDA, 80% 2,4-TDA : 20% 2,6-TDA).

Stage 3 (Liquid-Phase or Gas-Phase Phosgenation of TDA 80/20 to Crude TDI 80/20):
  In modern liquid-phase or gas-phase phosgenation reactors, a solution or vapor stream of m-TDA 80/20 dissolved in an inert chlorinated aromatic solvent (such as monochlorobenzene MCB or ortho-dichlorobenzene ODCB) is reacted with a stoichiometric excess of anhydrous phosgene (COCl2) at 70 to 220 °C via intermediate carbamoyl chlorides, evolving hydrogen chloride (HCl) gas:
  CH3-C6H3(NH2)2 (TDA 80/20) + 2 COCl2 (Phosgene)  --->  CH3-C6H3(NCO)2 (TDI 80/20) + 4 HCl (gas)

Stage 4 (Multi-Column Vacuum Distillation and Hydrolyzable Chlorine Stripping):
  Excess phosgene, HCl gas, and MCB/ODCB solvent are recovered and recycled, and the crude TDI is rectified under vacuum (10 to 30 mbar) in high-efficiency packed distillation columns with thermal dechlorination treatment to remove polymeric tar residues and reduce hydrolyzable chlorine below 50 to 100 ppm, yielding crystal-clear TDI (Toluene Diisocyanate) T80/20 (>= 99.5% purity, <= 15 APHA).

PHYSICAL AND CHEMICAL PROPERTIES OF TDI (TOLUENE DIISOCYANATE) T80/20

Quantitative physical properties and ASTM D1786 / ISO 14896 specification limits for Ataman Kimya's TDI (Toluene Diisocyanate) T80/20 (CAS 26471-62-5) include:
- Product Designation: Toluene Diisocyanate 80/20 (TDI T80/20, 80:20 isomer mixture of 2,4-TDI and 2,6-TDI)
- CAS Registry Numbers: 26471-62-5 (mixed isomers); 584-84-9 (2,4-TDI, 80%); 91-08-7 (2,6-TDI, 20%)
- EC / EINECS Numbers: 247-722-4 (mixed); 209-544-5 (2,4-TDI); 202-039-0 (2,6-TDI)
- Physical Appearance at 20 °C: Clear, colorless (water-white) to very pale yellow mobile liquid, free from sediment or turbidity
- Odor: Sharp, pungent, lachrymatory aromatic isocyanate odor (detectable only above safe occupational exposure limits—never rely on odor as a warning of exposure!)
- Purity / Total TDI Assay (GC / Titration, ASTM D5155): >= 99.5% w/w (typical 99.7% to 99.8% w/w)
- Isomer Ratio — 2,4-Toluene Diisocyanate (GC / IR, ASTM D4660): 80.0 +/- 1.0% w/w (79.0% to 81.0% w/w)
- Isomer Ratio — 2,6-Toluene Diisocyanate (GC / IR, ASTM D4660): 20.0 +/- 1.0% w/w (19.0% to 21.0% w/w)
- Isocyanate (-NCO) Content: 48.0% to 48.25% w/w (theoretical 48.23% w/w; Amine Equivalent <= 87.5 g/eq, theoretical 87.08 g/eq)
- Color (APHA / Pt-Co / Hazen, ASTM D1209): <= 15 to 25 APHA (typical <= 10 APHA)
- Hydrolyzable Chlorine (ASTM D4663 / ISO 15028): <= 0.010% w/w (<= 100 ppm; Type I grade typically <= 0.003% to 0.005% / 30 to 50 ppm; Type II grade controlled at 0.007% to 0.011% / 70 to 110 ppm)
- Total Chlorine (ASTM D4661): <= 0.05% to 0.10% w/w (<= 500 to 1,000 ppm; typical <= 200 ppm)
- Acidity (as HCl, ASTM D6099 / ISO 14898): <= 0.004% w/w (<= 40 ppm in Type I; 0.004% to 0.011% in Type II)
- Freezing / Crystallization Point: 11.5 to 14.0 °C (typically ~13.5 °C)
- Boiling Point at 101.3 kPa (760 mmHg): 251.0 °C (120 °C at 10 mmHg)
- Specific Gravity / Density (20/20 °C): 1.220 g/cm3 (at 25 °C: 1.215 g/cm3)
- Dynamic Viscosity at 20 °C: ~3.0 mPa·s (at 25 °C: ~2.4 mPa·s)
- Flash Point (Closed Cup, ASTM D93): 127.0 °C (Open Cup: 135.0 °C; Non-flammable Class IIIB Combustible Liquid)
- Vapor Pressure at 20 °C: ~0.015 to 0.025 hPa (0.011 to 0.019 mmHg; rises to 0.05 hPa at 30 °C and 0.53 hPa at 60 °C)
- Reactivity with Water: Reacts exothermically with water to evolve carbon dioxide (CO2) gas and form insoluble solid polyurea crusts

WHY EACH IMPORTANT PROPERTY OF TDI (TOLUENE DIISOCYANATE) T80/20 MATTERS IN PRACTICE

1. Strict Isomer Ratio Control (80.0 +/- 1.0% 2,4-TDI : 20.0 +/- 1.0% 2,6-TDI):
If the 2,4-TDI / 2,6-TDI ratio drifts outside 79:21 to 81:19—most commonly because a drum or tank of TDI (Toluene Diisocyanate) T80/20 was allowed to chill below +14 °C during winter transport, causing pure 2,4-TDI crystals (mp 21.8 °C) to freeze out on the container walls while enriching the remaining liquid in 2,6-TDI—foam processing fails catastrophically: liquid enriched in 2,6-TDI reacts too slowly early on and causes closed, tight cells or shrinkage, whereas remelted bottom layers enriched in 2,4-TDI react too fast and cause foam splitting or collapse!
2. Hydrolyzable Chlorine and Acidity (ASTM D1786 Type I versus Type II):
Trace hydrolyzable chlorine (present as carbamoyl chlorides or benzoyl chloride at 20 to 110 ppm) acts as a natural Brønsted/Lewis acid retarder that moderates the catalytic activity of tertiary amines and stannous octoate. Ultra-low acidity Type I TDI (Toluene Diisocyanate) T80/20 (acidity <= 40 ppm, hydrolyzable Cl <= 50 ppm) gives fast reactivity and ultra-low color in CASE prepolymers and HR molded foams, whereas controlled-acidity Type II TDI gives slightly wider stannous octoate processing latitude in certain traditional polyester slabstock foams.
3. High NCO Content (48.2% w/w) and Low Equivalent Weight (87.08 g/eq):
Because 100 g of TDI (Toluene Diisocyanate) T80/20 provides 1.148 equivalents of reactive -NCO groups (compared to only 0.74 to 0.80 equivalents for 100 g of polymeric MDI), formulators require ~30% less weight of isocyanate per ton of water-blown flexible foam when using TDI (Toluene Diisocyanate) T80/20, enabling ultra-low-density flexible slabstock foams (10 to 18 kg/m3) that cannot be achieved as economically with MDI alone.

HOW DOES TDI (TOLUENE DIISOCYANATE) T80/20 WORK AT THE MOLECULAR AND PROCESS LEVEL?

1. Phase-Separated Hard and Soft Segment Micro-Architecture in Flexible Polyurethane Foam:
When TDI (Toluene Diisocyanate) T80/20 reacts simultaneously with a high-molecular-weight trifunctional polyether polyol (MW 3,000 to 6,000 g/mol, Tg ~ -60 °C) and water (2.0 to 5.5 phr) in the presence of amine blowing catalysts and stannous octoate gelling catalyst, two distinct polymer blocks form in situ:
- Soft Elastic Segments: Formed by the reaction of TDI (Toluene Diisocyanate) T80/20 with flexible polyether chains via urethane bonds, providing rubbery elasticity and resilience.
- Rigid Polyurea Hard Segments: Formed by the reaction of TDI (Toluene Diisocyanate) T80/20 with water to generate toluene diamine (TDA), which immediately reacts with additional TDI molecules to form stiff, hydrogen-bonded aromatic polyurea chains. Because these rigid aromatic polyurea chains are thermodynamically immiscible with the soft polyether chains, they self-assemble into nano-scale physical crosslinking domains ("urea balls" and lamellae) that reinforce the cell struts and give the flexible foam high indentation load deflection (ILD) hardness and tear resistance.
2. Controlled NCO-Prepolymer Synthesis in Elastomers, Coatings, and Adhesives:
When 2.0 moles of TDI (Toluene Diisocyanate) T80/20 are reacted with 1.0 mole of a linear diol (such as PTMEG 1000, PPG 2000, or polycaprolactone diol) at 65 to 80 °C, the 4- to 8-fold faster para-NCO group at position C-4 of the 2,4-TDI isomer caps the hydroxyl ends of the diol selectively, while the sterically hindered C-2 ortho-NCO group remains unreacted at the chain terminals. This regioselectivity produces a narrow-molecular-weight-distribution NCO-prepolymer with significantly lower viscosity and lower residual monomeric TDI than non-selective symmetric diisocyanates.

WHAT PROBLEMS CAN TDI (TOLUENE DIISOCYANATE) T80/20 HELP SOLVE?

1. Achieving Ultra-Low Foam Densities (12 to 22 kg/m3) with High Cushioning Comfort and Open Breathability: Because TDI (Toluene Diisocyanate) T80/20 has a low equivalent weight (87.08 g/eq) and forms self-reinforcing aromatic polyurea hard domains upon reacting with water, it enables continuous slabstock foamers to produce soft, breathable, durable mattress and furniture foams down to 12–16 kg/m3 without structural collapse.
2. Eliminating Closed-Cell Shrinkage or Bun Splitting via Regioselective 80:20 Cure Balance: The balanced 80% 2,4-TDI / 20% 2,6-TDI isomer ratio provides rapid early gas retention via C-4 para-NCO reaction followed by controlled high-temperature C-2/C-6 ortho-NCO network completion, giving a wide "stannous octoate tin window" between foam splitting (too little tin) and closed-cell shrinkage (too much tin).
3. Lowering Prepolymer Viscosity and Extending Pot Life in Cast Elastomers and Sealants: Compared to symmetric 4,4'-MDI (which has equal reactivity at both NCO groups and forms high-viscosity oligomers during prepolymer synthesis), the asymmetric reactivity of TDI (Toluene Diisocyanate) T80/20 yields lower-viscosity NCO-prepolymers that pour, degas, and wet substrates effortlessly and cure with aromatic diamines (MOCA / DMTDA) to give Shore A 60 to Shore D 75 elastomers with superior dynamic flex-fatigue life.
4. Delivering Fast Tack-Free Drying and Chemical Resistance in Wood Coatings and Packaging Adhesives: When converted into TDI-TMP adducts (such as 75% solids in ethyl acetate) or TDI-isocyanurate trimers, TDI (Toluene Diisocyanate) T80/20 provides rapid room-temperature drying, high gloss, and solvent/scratch resistance in 2K polyurethane wood furniture varnishes and high-speed flexible food-packaging laminating adhesives.

BENEFITS FOR THE MANUFACTURER AND END USER

- Highest Isocyanate Efficiency per Ton (48.2% w/w NCO): Delivers more reactive isocyanate equivalents per kilogram than any other commercial aromatic diisocyanate, reducing raw material cost per cubic meter of flexible foam.
- Water-White Clarity and Ultra-Low Viscosity (2.4 mPa·s at 25 °C): Pumps, meters, and atomizes cleanly at low pressures in high-output Maxfoam, Varimax, Vertifoam, and high-pressure impingement mixheads.
- Tunable Hardness Across Isocyanate Indices (Index 85 to 120): Simply varying the water level and TDI (Toluene Diisocyanate) T80/20 Isocyanate Index allows a single slabstock line to manufacture everything from ultra-soft viscoelastic ("memory") and hypersoft topper foams to extra-firm orthopedic mattress cores and high-load packaging foams.
- Consistent Lot-to-Lot Reactivity Profile: Strict control of 80.0 +/- 1.0% isomer ratio and <= 50 ppm hydrolyzable chlorine from Ataman Kimya eliminates daily catalyst re-tuning on the foaming line.

APPLICATIONS OF TDI (TOLUENE DIISOCYANATE) T80/20

TDI (Toluene Diisocyanate) T80/20 is utilized across a wide spectrum of flexible foam, automotive, elastomer, coating, adhesive, and sealant applications:
TDI (Toluene Diisocyanate) T80/20 is utilized as the primary diisocyanate monomer in Continuous and Batch Flexible Polyether & Polyester Polyurethane Slabstock Foams for mattresses, pillows, viscoelastic memory foams, sofa cushions, upholstered furniture, acoustic soundproofing panels, sponges, and textile flame-lamination rolls.
TDI (Toluene Diisocyanate) T80/20 is used for Hot-Cure and High-Resilience (HR) Cold-Cure Molded Flexible Polyurethane Foams (alone or in 80:20 / 60:40 blends with polymeric MDI) in automotive car/truck seating pads, headrests, armrests, motorcycle saddles, and ergonomic office chairs.
Also TDI (Toluene Diisocyanate) T80/20 is utilized in the preparation of Cast Polyurethane Elastomers (CPU) and Millable Polyurethane Gums by reacting with PTMEG, PPG, or polyester diols to form NCO-prepolymers cured with MOCA or DMTDA for industrial fork-lift tires, printing/steel-mill rollers, mining hydrocyclones, pipeline pigs, and mechanical seals.

For Two-Component (2K) and One-Component (1K) Polyurethane Wood, Parquet, Anticorrosion, and Leather Coatings, TDI (Toluene Diisocyanate) T80/20 is used to manufacture low-free-monomer TDI-TMP adducts (CAS 53317-61-6), TDI-isocyanurate trimers, and moisture-cure urethane prepolymers.
In Solvent-Borne, Solvent-Free, and Reactive Polyurethane Adhesives and Binders, TDI (Toluene Diisocyanate) T80/20 is employed to produce flexible food-packaging film laminating adhesives, footwear sole adhesives, rebonded foam binders, and rubber-crumb running-track/playground binders.
Furthermore, TDI (Toluene Diisocyanate) T80/20 is applied in One-Component and Two-Component Polyurethane Construction Sealants, Potting Compounds, and Waterproofing Membranes based on PPG polyether prepolymers.
Additionally, TDI (Toluene Diisocyanate) T80/20 is utilized as a reactive chemical intermediate in the synthesis of Urethane Acrylate UV-Curable Oligomers, Blocked Isocyanate Crosslinkers (for coil coatings, wire enamels, and textile treatments), Polyimide/Polyamide-Imide High-Temperature Resins, and Dimeric Toluene-2,4-Diisocyanate rubber adhesion promoters.

WHICH INDUSTRIES USE TDI (TOLUENE DIISOCYANATE) T80/20?

- The Flexible Polyurethane Slabstock Foam, Mattress, Bedding, and Upholstered Furniture Manufacturing Industry uses TDI (Toluene Diisocyanate) T80/20 as its core isocyanate raw material.
- The Automotive OEM Seating, Interior Acoustic Trim, and Molded Foam Industry utilizes TDI (Toluene Diisocyanate) T80/20 for high-resilience, low-fatigue vehicular seating cushions.
- The Cast Polyurethane Elastomer (CPU), Industrial Roller, Mining Screen, and Mechanical Goods Industry relies on TDI (Toluene Diisocyanate) T80/20 prepolymers for high-abrasion, low-hysteresis elastomer parts.
- The Wood Coating, Parquet Varnish, Industrial Paint, and UV-Curable Resin Industry employs TDI (Toluene Diisocyanate) T80/20 to produce TDI-TMP adducts, trimers, and urethane acrylates.
- The Flexible Packaging Laminating Adhesive, Footwear Adhesive, Construction Sealant, and Sports Flooring Binder Industry uses TDI (Toluene Diisocyanate) T80/20 to formulate high-bond-strength polyurethane prepolymers.
- The Specialty Chemical Intermediate, Wire Enamel, and Textile Auxiliary Industry utilizes TDI (Toluene Diisocyanate) T80/20 to synthesize blocked isocyanates and specialty crosslinkers.

USE OF TDI (TOLUENE DIISOCYANATE) T80/20 IN FLEXIBLE SLABSTOCK FOAMS, AUTOMOTIVE MOLDED SEATING AND REBONDED FOAMS

- Continuous and Box-Pour Flexible Polyether & Polyester Slabstock Foams with TDI (Toluene Diisocyanate) T80/20: In conventional polyether slabstock foam lines (using 3,000 to 3,500 MW glycerine-initiated PO/EO polyether triols, OHv = 48 to 56 mg KOH/g), TDI (Toluene Diisocyanate) T80/20 is metered at an Isocyanate Index of 95 to 115 alongside 1.8 to 5.0 phr water (and optional liquid CO2 or methylene chloride/methylal auxiliary blowing agent), 0.8 to 1.4 phr silicone-polyether surfactant, 0.10 to 0.35 phr tertiary amine catalysts (BDMAEE + TEDA), and 0.12 to 0.30 phr stannous octoate (T-9). In High-Resilience (HR) slabstock foams (using 4,800 to 6,000 MW primary-hydroxyl-capped polyether polyols and SAN/PHD copolymer polyols), TDI (Toluene Diisocyanate) T80/20 is processed with diethanolamine (DEOA) crosslinker and dibutyltin dilaurate (DBTDL) to produce luxury high-sag-factor mattresses. In technical Ester Foams (based on adipate polyester polyols for automotive flame-lamination textiles and acoustic filters), TDI (Toluene Diisocyanate) T80/20 (often blended with TDI 65/35) yields ultra-uniform pinhole-free cell reticulation.
- Automotive Hot-Cure and Cold-Cure HR Molded Seating with TDI (Toluene Diisocyanate) T80/20: Automotive seat cushions and backrests require rapid demold times (3 to 5 minutes in 55–65 °C heated aluminum molds), high comfort factor (Sag Factor >= 2.8), and low wet compression set. Formulators use either 100% TDI (Toluene Diisocyanate) T80/20 or a synergistic 80:20 / 70:30 blend of TDI (Toluene Diisocyanate) T80/20 with polymeric MDI reacted with high-MW EO-capped polyether triols and grafted copolymer polyols (SAN/PIPA).

USE OF TDI (TOLUENE DIISOCYANATE) T80/20 IN CAST ELASTOMERS (CPU), COATINGS, ADHESIVES AND SEALANTS (CASE)

- Cast Polyurethane Elastomers (PTMEG / Polyester Prepolymers) with TDI (Toluene Diisocyanate) T80/20: Reacting TDI (Toluene Diisocyanate) T80/20 with anhydrous polytetramethylene ether glycol (PTMEG 1000 or 2000) or ethylene/butylene adipate polyester diols at an NCO/OH molar ratio of 1.8:1 to 2.2:1 produces liquid prepolymers containing 3.2% to 9.5% w/w free NCO. When degassed at 80–90 °C and cured at 95% stoichiometric index with MOCA or DMTDA (Ethacure 300), TDI-based elastomers exhibit superior heat-buildup resistance (low tan delta hysteresis) under high-speed cyclic loading compared to MDI elastomers—making TDI (Toluene Diisocyanate) T80/20 the industry standard for high-load forklift wheels, elevator guide rollers, and paper-mill rolls.
- 2K Wood Coatings, Packaging Adhesives, and Construction Sealants with TDI (Toluene Diisocyanate) T80/20: Because monomeric TDI (Toluene Diisocyanate) T80/20 has a noticeable vapor pressure (~0.02 hPa at 20 °C), coating and adhesive manufacturers react 3.0 moles of TDI (Toluene Diisocyanate) T80/20 with 1.0 mole of Trimethylolpropane (TMP) in ethyl acetate followed by thin-film vacuum stripping to produce low-free-monomer (< 0.5% free TDI) TDI-TMP Polyisocyanate Hardener (75% solids, ~13.3% NCO), widely used as the curing agent for fast-drying 2K polyurethane wood varnishes and flexible packaging laminating adhesives.

FORMULATION AND PROCESS CONSIDERATIONS WHEN USING TDI (TOLUENE DIISOCYANATE) T80/20

Equivalent Weight and Isocyanate Index Calculation for TDI (Toluene Diisocyanate) T80/20:
Because the molecular weight of TDI (Toluene Diisocyanate) T80/20 is 174.16 g/mol and its functionality is 2.00, its exact Equivalent Weight is 87.08 g/eq (corresponding to 48.23% w/w NCO). In polyurethane formulation calculations:
- 1.00 g of Water (MW 18.015 g/mol, equivalent weight 9.008 g/eq as a difunctional reactant with NCO) consumes exactly 87.08 / 9.008 = 9.667 g of pure TDI (Toluene Diisocyanate) T80/20 at 100 Index!
- 100.0 g of a Polyether Polyol with Hydroxyl Value (OHv, in mg KOH/g) consumes (OHv / 56,100) x 87.08 x 100 = 0.1552 x OHv grams of TDI (Toluene Diisocyanate) T80/20 at 100 Index!
- Therefore, the exact parts per hundred polyol (phr) of TDI (Toluene Diisocyanate) T80/20 required at a target Isocyanate Index (e.g., Index = 108) is:
  TDI (phr) = [ (0.1552 x Polyol OHv) + (9.667 x Total Water phr) + (Crosslinker Equivalents x 87.08) ] x (Isocyanate Index / 100)

Preventing Partial Freezing (+14 °C Threshold) and Isomer Segregation:
The single most critical physical handling rule for TDI (Toluene Diisocyanate) T80/20 is temperature control between +18 °C and +30 °C (never below +15 °C and never above +40 °C). If a drum, IBC, or ISO tank of TDI (Toluene Diisocyanate) T80/20 cools below +14 °C during winter transit, the higher-melting 2,4-TDI isomer (melting point +21.8 °C) crystallizes out first at the bottom and walls of the container, leaving the remaining liquid depleted in 2,4-TDI and enriched in 2,6-TDI! Never withdraw liquid from a partially frozen container of TDI (Toluene Diisocyanate) T80/20! If crystallization occurs, the entire container must be gently warmed in a hot-air room at 35 to 40 °C (never using local open flames, steam lances, or electric band heaters above 45 °C, which promote uretdione dimerization) until 100% melted, and then thoroughly homogenized by rolling or closed-loop circulation before use.

Controlling Exothermic Runaway in High-Water, Low-Density Slabstock Foams:
The reaction of 1.0 mole of water with TDI (Toluene Diisocyanate) T80/20 releases ~195 kJ of heat. In ultra-low-density foams boosted solely with water (> 4.5 to 5.2 phr water), internal bun core temperatures can approach or exceed 165 to 170 °C—risking core scorching (yellow/brown thermo-oxidative discoloration) or spontaneous bun auto-ignition hours after production if cured buns are stacked without cooling. Limit total water to <= 4.5–4.8 phr (using liquid CO2 or physical blowing agents for lower densities), keep Isocyanate Index <= 112 in high-water grades, include 0.3 to 0.5 phr anti-scorch antioxidant package, and cure fresh buns in ventilated cooling racks.

TYPICAL USE LEVELS AND INITIAL FORMULATION APPROACHES FOR TDI (TOLUENE DIISOCYANATE) T80/20

Typical commercial stoichiometric incorporation levels for TDI (Toluene Diisocyanate) T80/20 depend on the polyol hydroxyl value, water loading, and target Isocyanate Index:
- Conventional Flexible Polyether Slabstock Foams (Density 16 to 35 kg/m3, Water 2.2 to 4.8 phr, Polyol OHv 48–56 mg KOH/g): TDI (Toluene Diisocyanate) T80/20 is metered at 32.0 to 58.0 phr on polyol (corresponding to an Isocyanate Index of 98 to 112).
- High-Resilience (HR) Slabstock and Automotive Cold-Cure Molded Foams (Density 32 to 55 kg/m3, Water 2.5 to 3.8 phr, Polyol OHv 28–36 mg KOH/g + DEOA Crosslinker): TDI (Toluene Diisocyanate) T80/20 is dosed at 30.0 to 46.0 phr on polyol (Isocyanate Index 90 to 108).
- Viscoelastic ("Memory") Low-Resilience Foams (Density 40 to 65 kg/m3, Water 1.2 to 2.0 phr): TDI (Toluene Diisocyanate) T80/20 is formulated at 24.0 to 36.0 phr on polyol (typically at a low Isocyanate Index of 78 to 92 to create dangling chain ends that maximize mechanical damping).
- Cast Polyurethane Elastomer (CPU) NCO-Prepolymers (PTMEG / PPG / Polyester Diols, MW 1,000–2,000 g/mol): TDI (Toluene Diisocyanate) T80/20 is reacted at an NCO/OH molar ratio of 1.75:1 to 2.20:1 (typically 18% to 38% w/w TDI on total prepolymer batch) to yield prepolymers with 3.5% to 9.5% w/w free NCO.
- TDI-TMP 75% Adduct Hardeners for 2K Wood Coatings and Packaging Adhesives: TDI (Toluene Diisocyanate) T80/20 is reacted at ~3.0 to 3.2 moles per 1.0 mole of Trimethylolpropane (TMP) in ethyl acetate (roughly 79.5% w/w TDI : 20.5% w/w TMP on dry solids), followed by vacuum monomer stripping.
- One-Component (1K) Moisture-Cure Polyurethane Sealants, Binders, and Floor Coatings: TDI (Toluene Diisocyanate) T80/20 is reacted with dried PPG diols/triols at 12% to 25% w/w on polyol to yield low-viscosity prepolymers containing 2.0% to 6.5% w/w free NCO.
The four laboratory and pilot frameworks below illustrate preliminary R&D evaluation protocols for qualified technical personnel formulating with TDI (Toluene Diisocyanate) T80/20.

EXAMPLE 1: BENCH-SCALE FORMULATION AND FOAMING OF A 25 KG/M3 CONVENTIONAL FLEXIBLE POLYETHER SLABSTOCK MATTRESS FOAM (INDEX 108)

Purpose: To calculate exact stoichiometric TDI dosage, evaluate the stannous octoate "tin window", and measure cream time, full-rise time, air permeability, indentation hardness (IFD/CLD), and compression set of a 25 kg/m3 flexible slabstock foam produced with TDI (Toluene Diisocyanate) T80/20.
Initial screening formulation (parts per hundred polyol, phr; Target Isocyanate Index = 108):
- Trifunctional Polyether Polyol (glycerine-initiated PO/EO heteropolymer, MW 3,000 g/mol, OHv = 56.0 mg KOH/g, moisture = 0.04% w/w): 100.00 phr
- Deionized Water (added chemical blowing agent; total water including polyol moisture = 4.04 phr): 4.00 phr
- Silicone-Polyether Block Copolymer Slabstock Surfactant (medium-activity cell stabilizer): 1.10 phr
- Bis(2-dimethylaminoethyl)ether (BDMAEE, 70% in DPG, selective water-blowing amine catalyst): 0.12 phr
- Triethylenediamine (TEDA, 33% in DPG, balanced gelling/blowing amine catalyst): 0.25 phr
- Stannous Octoate (T-9, 100% active tin gelling catalyst): evaluated at 0.18, 0.21, and 0.24 phr to map the tin window
- TDI (Toluene Diisocyanate) T80/20 (CAS 26471-62-5, Ataman Kimya ASTM D1786 Type I Grade, 80.0% 2,4-TDI : 20.0% 2,6-TDI, assay 99.7%, NCO = 48.2%, eq wt = 87.08 g/eq): 51.60 phr (Stoichiometric calculation at 100 Index: Polyol requires 0.1552 x 56.0 = 8.69 phr TDI; Total Water 4.04 phr requires 4.04 x 9.667 = 39.05 phr TDI; DPG solvent in amine catalysts ~0.27 phr requires ~0.35 phr TDI; Total at 100 Index = 47.78 phr; at 108 Index = 47.78 x 1.08 = 51.60 phr TDI)
Laboratory evaluation procedure:
- Stage 1 (Temperature Conditioning and Polyol/Additive Pre-Mixing): Equilibrate all components to 22.0 +/- 0.5 °C in a ventilated fume hood equipped with local exhaust extraction. In a 1-liter polypropylene mixing cup, weigh 200.0 g polyether polyol, 8.00 g deionized water, 2.20 g silicone surfactant, 0.24 g BDMAEE (70%), and 0.50 g TEDA (33%), and premix at 1,500 rpm for 45 seconds using a high-shear 65 mm Conn blade mixer to disperse air nucleation bubbles (~20 mL/L air loading).
- Stage 2 (Stannous Octoate Addition and High-Speed TDI Mixing): Add 0.42 g (0.21 phr) Stannous Octoate via syringe, stir at 1,500 rpm for 8 seconds, then immediately pour in 103.20 g (51.60 phr) of TDI (Toluene Diisocyanate) T80/20 and mix at 2,800 rpm for exactly 6.0 seconds. Immediately dump the reacting liquid into a 300 x 300 x 300 mm open wooden box lined with kraft paper.
- Stage 3 (Reactivity Profile and Cured Foam Physical Testing): Record Cream Time (target 8 to 10 seconds), Full-Rise Time (target 90 to 105 seconds), and healthy summit gas blow-off (1 to 2 seconds after full rise, indicating open cells). Cure the foam block in a ventilated oven at 100 °C for 15 minutes, condition for 24 hours at 23 °C / 50% RH, and cut test samples: verify core density = 24.5 +/- 0.8 kg/m3 (ISO 845), 40% Compression Load Deflection hardness CLD 40% = 3.6 to 4.0 kPa (ISO 3386-1), air flow permeability = 80 to 115 L/min (ASTM D3574 Test G, confirming open-cell breathability), tensile strength >= 110 kPa, elongation >= 180% (ISO 1798), and 75% compression set (22 h at 70 °C, ISO 1856) <= 6.0%.

EXAMPLE 2: AUTOMOTIVE HIGH-RESILIENCE (HR) COLD-CURE MOLDED SEAT CUSHION FOAM USING TDI (TOLUENE DIISOCYANATE) T80/20

Purpose: To formulate a 45 kg/m3 High-Resilience (HR) molded automotive seating cushion foam using TDI (Toluene Diisocyanate) T80/20, grafted copolymer polyol, and DEOA crosslinker, and evaluate 5-minute demoldability, Sag Factor (comfort index), and wet compression set.
Initial HR molded foam formulation (parts per hundred total polyol, phr; Target Isocyanate Index = 100):
- High-MW Primary-Hydroxyl-Capped Polyether Triol (MW 5,000–6,000 g/mol, > 80% primary OH groups, OHv = 32.0 mg KOH/g): 70.0 phr
- Styrene-Acrylonitrile (SAN) Grafted Copolymer Polyol (43% solid SAN dispersed in HR carrier polyol, OHv = 20.0 mg KOH/g, load-bearing booster): 30.0 phr
- Deionized Water (chemical blowing agent): 3.20 phr
- Diethanolamine (DEOA, 85% aqueous solution, trifunctional amine/OH chain extender & crosslinker): 1.40 phr
- Triethylenediamine (TEDA, 33% in DPG, gelling catalyst): 0.45 phr
- Bis(2-dimethylaminoethyl)ether (BDMAEE, 70% in DPG, blowing catalyst): 0.10 phr
- Dibutyltin Dilaurate (DBTDL, delayed-action urethane catalyst): 0.05 phr
- Low-Activity Polydimethylsiloxane HR Molded Foam Surfactant (cell regulator): 0.90 phr
- TDI (Toluene Diisocyanate) T80/20 (CAS 26471-62-5, Ataman Kimya ASTM D1786 Type I Grade, 80:20 isomer ratio, NCO = 48.2%): 40.20 phr (Index = 100)
Laboratory evaluation procedure:
- Blend the 70.0 phr base HR polyol, 30.0 phr SAN copolymer polyol, 3.20 phr water, 1.40 phr DEOA (85%), 0.45 phr TEDA, 0.10 phr BDMAEE, 0.05 phr DBTDL, and 0.90 phr HR silicone surfactant at 23 °C to form the formulated B-side masterbatch.
- Preheat a 400 x 400 x 100 mm clamped cast-aluminum test mold to 60 +/- 2 °C and apply a thin coat of wax mold-release agent.
- Mix the B-side masterbatch with 40.20 phr of TDI (Toluene Diisocyanate) T80/20 at 3,200 rpm for 5 seconds, pour the calculated mold-fill weight (targeting 45 kg/m3 molded density at 10% overpack) into the 60 °C aluminum mold, and close the lid immediately.
- Demold at exactly 5.0 minutes, pass the hot molded cushion through a two-roll mechanical cell crusher (50% gap compression) to burst residual closed cell windows, post-cure for 24 hours at 23 °C, and test per automotive OEM standards: confirm Molded Density = 45.0 kg/m3, IFD Sag Factor (65% IFD / 25% IFD ratio per ASTM D3574 Test B1) >= 2.95, Ball Rebound Resilience >= 60% (ASTM D3574 Test H), hysteresis loss <= 22%, and 50% Humid Aged Compression Set (50 °C / 95% RH for 22 hours) <= 12%.

EXAMPLE 3: SYNTHESIS OF A SHORE A 90 PTMEG-TDI CAST POLYURETHANE ELASTOMER PREPOLYMER (6.3% FREE NCO) AND MOCA CURING

Purpose: To synthesize an NCO-terminated polyether urethane prepolymer (Adiprene L-167 / Vibrathane B625 equivalent, ~6.3% w/w free NCO) by reacting anhydrous PTMEG-1000 diol with a 2.0:1.0 molar ratio of TDI (Toluene Diisocyanate) T80/20, and cast Shore A 90 elastomer test slabs cured with MOCA.
Initial prepolymer synthesis charge (per 1,000.0 g reactor batch, NCO/OH molar ratio = 2.00 : 1.00):
- Polytetramethylene Ether Glycol (PTMEG-1000, CAS 25190-06-1, MW = 1,000.0 g/mol, OHv = 112.2 mg KOH/g, vacuum-dehydrated to moisture <= 0.015% w/w): 741.6 g (0.7416 moles = 1.4832 equivalents OH)
- TDI (Toluene Diisocyanate) T80/20 (CAS 26471-62-5, Ataman Kimya Type I Low-Acidity Grade, MW = 174.16 g/mol, 80% 2,4-TDI : 20% 2,6-TDI, assay >= 99.7%, hydrolyzable Cl <= 30 ppm): 258.3 g (1.4832 moles = 2.9664 equivalents NCO; exact 2.00:1.00 molar ratio to PTMEG-1000)
- Benzoyl Chloride (stabilizing acid trace to prevent allophanate branching during hot storage): 0.10 g (100 ppm)
Laboratory evaluation procedure:
- Stage 1 (Regioselective Prepolymer Synthesis): Charge the 258.3 g of TDI (Toluene Diisocyanate) T80/20 and 0.10 g benzoyl chloride into a dry, nitrogen-blanketed 2-liter four-neck glass reactor equipped with a mechanical stirrer, thermometer, and dropping funnel at 45 °C. Slowly feed the molten, vacuum-dried 741.6 g PTMEG-1000 into the agitated TDI over 45 minutes while maintaining reactor temperature at 60 to 65 °C. Because the unhindered C-4 para-NCO group of the 2,4-TDI isomer reacts ~6 times faster than the hindered C-2 ortho-NCO group at 65 °C, each end of the PTMEG-1000 diol is selectively capped with one TDI molecule!
- Stage 2 (Reaction Completion and Vacuum Degassing): Hold the batch at 75 to 80 °C under nitrogen for 2.0 hours until di-n-butylamine back-titration (ASTM D2572) confirms that free NCO content has reached the theoretical value of 6.30 +/- 0.10% w/w (equivalent weight ~667 g/eq) and Brookfield viscosity at 85 °C is ~650 to 850 mPa·s. Apply 5 mbar vacuum at 80 °C for 30 minutes to degas completely.
- Stage 3 (MOCA Chain Extension and Elastomer Casting): Preheat 200.0 g of the degassed PTMEG-TDI prepolymer to 85 °C (0.200 x 6.30 / 42.02 = 0.300 equivalents NCO). Melt 38.0 g of 4,4'-Methylenebis(2-chloroaniline) (MOCA, eq wt = 133.5 g/eq; 95% stoichiometric index = 0.300 x 0.95 x 133.5 = 38.05 g) at 115 °C, blend thoroughly with the 85 °C prepolymer for 60 seconds without air entrapment (pot life ~7 minutes), pour into a 100 °C preheated steel mold, demold after 45 minutes, and post-cure at 100 °C for 16 hours. Verify cured physical properties: Shore A Hardness = 90 +/- 2, Tensile Strength >= 38 MPa (ASTM D412), Elongation at Break >= 430%, Graves Tear Strength (Die C, ASTM D624) >= 85 kN/m, and Bashore Rebound >= 48%.

EXAMPLE 4: SYNTHESIS OF A 75% SOLIDS TDI-TMP POLYISOCYANATE CROSSLINKER ADDUCT FOR 2K WOOD VARNISHES AND PACKAGING ADHESIVES

Purpose: To synthesize a 75% non-volatile solids aromatic polyisocyanate curing agent (TDI-TMP Adduct in Ethyl Acetate, ~13.3% w/w NCO on solution) by reacting TDI (Toluene Diisocyanate) T80/20 with Trimethylolpropane (TMP).
Initial reactor charge (per 1,000.0 g solution batch at 75.0% w/w solids in anhydrous Ethyl Acetate):
- Urethane-Grade Anhydrous Ethyl Acetate (CAS 141-78-6, purity >= 99.8%, water <= 0.02% w/w, alcohol <= 0.02%): 250.0 g (25.0% w/w solvent)
- TDI (Toluene Diisocyanate) T80/20 (CAS 26471-62-5, Ataman Kimya Type I Grade, 80% 2,4-TDI : 20% 2,6-TDI): 596.0 g (3.422 moles = 6.844 equivalents NCO)
- Trimethylolpropane Flakes (TMP, CAS 77-99-6, MW 134.17 g/mol, eq wt 44.72 g/eq, vacuum-dried at 70 °C to moisture <= 0.03%): 154.0 g (1.148 moles = 3.443 equivalents OH; NCO/OH equivalent ratio ~ 1.99 : 1.00)
Laboratory evaluation procedure:
- Charge the 250.0 g anhydrous ethyl acetate and 596.0 g TDI (Toluene Diisocyanate) T80/20 into a dry nitrogen-purged reactor equipped with a reflux condenser at 50 °C.
- Feed the molten 154.0 g anhydrous Trimethylolpropane (pre-melted at 65 °C) incrementally over 90 minutes while controlling the exothermic urethane reaction at 65 to 75 °C with jacket cooling.
- Maintain at 75 °C for 3.0 hours until ASTM D2572 titration confirms that the solution NCO content stabilizes at 13.3 +/- 0.3% w/w (equivalent weight ~315 g/eq on solution), solids content is 75.0 +/- 1.0% w/w, color is <= 30 APHA, and Brookfield viscosity at 25 °C is 1,200 to 1,800 mPa·s. (In industrial production of ultra-low-monomer < 0.5% free TDI grades, a larger excess of TDI is used followed by thin-film vacuum distillation of unreacted monomer and re-dilution to 75% solids in ethyl acetate.)
- Formulate a 2K Polyurethane Wood Clearcoat by blending 100.0 g of an OH-functional alkyd/acrylic resin (3.2% OH on solution) with 59.0 g of the 75% TDI-TMP Adduct (NCO:OH = 1.05:1.00) in butyl acetate/xylene, apply at 100 microns wet film thickness onto oak veneer panels, and verify dust-free drying in <= 20 minutes at 23 °C, through-cure hardness (Konig pendulum hardness >= 165 seconds after 7 days), and 60° gloss >= 92 GU.

COMPATIBILITY AND INCOMPATIBILITY OF TDI (TOLUENE DIISOCYANATE) T80/20

- Compatible Non-Reactive Solvents and Co-Additives:
  - Urethane-Grade Apolar & Polar Aprotic Solvents (Moisture <= 0.02%–0.05% w/w): TDI (Toluene Diisocyanate) T80/20 is completely miscible with anhydrous ethyl acetate, n-butyl acetate, 1-methoxy-2-propyl acetate (PMA), methyl ethyl ketone (MEK), acetone, toluene, xylene, monochlorobenzene, ortho-dichlorobenzene, and non-hydroxyl plasticizers/flame retardants (such as TCPP, TBEP, DOTP, DINP, and chlorinated paraffins).
  - Compatible Co-Isocyanates: Miscible in all proportions with TDI 65/35, pure 2,4-TDI, monomeric 4,4'-/2,4'-MDI, polymeric MDI (PMDI), HDI trimers, and IPDI.
- Severe Chemical and Material Incompatibilities (Reactive Hazards!):
  - Water, Moisture, and Aqueous Solutions: NEVER allow water to enter a closed drum, IBC, or storage tank of TDI (Toluene Diisocyanate) T80/20! Even small amounts of water react with TDI (Toluene Diisocyanate) T80/20 to generate carbon dioxide (CO2) gas and insoluble solid polyurea crusts; in a sealed drum or unvented pipeline, CO2 gas evolution can build extreme internal pressure and rupture the container violently!
  - Strong Bases, Amines, Alcohols, and Acids: Violent, highly exothermic polymerization or addition reactions occur upon mixing bulk TDI (Toluene Diisocyanate) T80/20 with primary/secondary aliphatic amines, alkanolamines (diethanolamine, triethanolamine), strong alkalies (NaOH, KOH, aqueous ammonia), alcohols, glycols, or concentrated acids without heat removal.
  - Copper, Brass, Zinc, and Unsuitable Plastics: Never use copper, brass, bronze, tin, or galvanized zinc fittings or pipes with TDI (Toluene Diisocyanate) T80/20, as trace metal ions catalyze self-addition dimerization/trimerization and discolor the isocyanate. Undiluted TDI attacks and dissolves PVC, polystyrene, ABS, polycarbonate, polyurethane, and nitrile/natural rubber seals; always use stainless steel (304/316L), baked phenolic-lined carbon steel, PTFE (Teflon), Viton (FKM), or dry-nitrogen-blanketed equipment.

TDI (TOLUENE DIISOCYANATE) T80/20 AND TDI 65/35 (65% 2,4-TDI : 35% 2,6-TDI)

TDI 65/35 contains a higher proportion (35% w/w) of the symmetric, sterically hindered 2,6-TDI isomer and 65% w/w of the 2,4-TDI isomer (freezing point ~4 to 8 °C). Because the 2,6-TDI isomer builds linear, symmetric polyurea chains and provides slower late-stage curing, TDI 65/35 is used selectively in specialized reticulated polyester slabstock foams and certain high-hardness load-bearing foams, whereas TDI (Toluene Diisocyanate) T80/20 is the universal workhorse for 95%+ of polyether slabstock, HR molded foams, and CASE prepolymers.

TDI (TOLUENE DIISOCYANATE) T80/20 AND PURE 2,4-TDI (TDI 100, CAS 584-84-9)

Pure 2,4-TDI (TDI 100, >= 99.0% 2,4-isomer, melting point +21.8 °C) contains only the asymmetric 2,4-isomer. While TDI 100 provides the highest para- versus ortho-NCO selectivity for specialty optical/medical cast elastomers and ultra-low-free-monomer prepolymers, it freezes into a solid block at room temperature (< 22 °C) and is substantially more expensive than TDI (Toluene Diisocyanate) T80/20.

TDI (TOLUENE DIISOCYANATE) T80/20 AND DIPHENYLMETHANE DIISOCYANATE (MONOMERIC / POLYMERIC MDI, CAS 101-68-8 / 9016-87-9)

MDI has a higher molecular weight (250.25 g/mol for monomeric MDI; ~340–380 g/mol for polymeric MDI, functionality 2.2 to 2.8), lower NCO content (31.0% to 33.6% w/w versus 48.2% for TDI), and very low ambient vapor pressure (< 0.00001 hPa at 20 °C). Polymeric MDI dominates rigid thermal insulation foams (PUR/PIR panels, spray foam, appliance insulation), whereas TDI (Toluene Diisocyanate) T80/20 dominates flexible slabstock bedding/furniture foams (where TDI achieves much lower foam densities of 12–28 kg/m3, higher resilience, lower hysteresis loss, and lower isocyanate weight consumption per cubic meter).

TDI (TOLUENE DIISOCYANATE) T80/20 AND ALIPHATIC DIISOCYANATES (HDI CAS 822-06-0 / IPDI CAS 4098-71-9)

Aliphatic diisocyanates like Hexamethylene Diisocyanate (HDI) and Isophorone Diisocyanate (IPDI) lack aromatic benzene rings, so coatings and elastomers based on HDI/IPDI do not yellow under outdoor UV sunlight (whereas aromatic polyurethanes based on TDI or MDI form quinone-imide chromophores that yellow upon UV exposure). However, HDI and IPDI are 5 to 10 times slower-reacting and far more expensive than TDI (Toluene Diisocyanate) T80/20, making TDI (Toluene Diisocyanate) T80/20 the undisputed choice for all indoor foams, primers, wood sealers, adhesives, and mechanical elastomers where colour change does not affect mechanical properties.

QUALITY GRADES, QUALITY CONTROL AND PURCHASING CRITERIA FOR TDI (TOLUENE DIISOCYANATE) T80/20

Ataman Kimya supplies TDI (Toluene Diisocyanate) T80/20 in compliance with ASTM D1786 and ISO 14896 specifications:
1. ASTM D1786 Type I Grade TDI (Toluene Diisocyanate) T80/20 (Low-Acidity / Low-Chlorine Universal Grade):
The global benchmark grade for polyether flexible slabstock foams, HR automotive molded foams, viscoelastic foams, cast elastomer prepolymers (PTMEG/PPG/polyester), and CASE coatings/adhesives. Features Total TDI Purity >= 99.5% w/w (typical 99.7%), Isomer Ratio 80.0 +/- 1.0% 2,4-TDI and 20.0 +/- 1.0% 2,6-TDI, Color <= 15 APHA, Acidity (as HCl) <= 0.004% (40 ppm max), and Hydrolyzable Chlorine <= 0.005% to 0.010% (50 to 100 ppm max).
2. ASTM D1786 Type II Grade TDI (Toluene Diisocyanate) T80/20 (Controlled-Acidity Polyester Foam Grade):
Contains a tightly controlled acidity level of 0.004% to 0.011% w/w (as HCl) and hydrolyzable chlorine of 0.007% to 0.012% w/w to moderate amine/tin catalysis in specific technical polyester slabstock foam formulations.
Incoming quality control testing includes ASTM D4660 isomer ratio determination by GC or FTIR (measuring the 810 cm^-1 and 782 cm^-1 out-of-plane C-H bending bands of 2,4-TDI and 2,6-TDI), ASTM D5155 / D2572 di-n-butylamine NCO titration, ASTM D4663 hydrolyzable chlorine, and ASTM D1209 APHA color.

STORAGE AND HANDLING OF TDI (TOLUENE DIISOCYANATE) T80/20

- Commercial Packaging Formats from Ataman Kimya:
  - 250 kg net tight-head (closed-top) steel drums (internally clean cold-rolled steel or baked phenolic-epoxy lined, purged with dry nitrogen prior to sealing, 4 drums per pallet = 1,000 kg net).
  - 1,000 to 1,150 kg net specialized UN-approved IBCs (where permitted by regional ADR/IMDG regulations).
  - 20,000 to 24,000 kg net bulk insulated, temperature-controlled stainless-steel ISO tank containers equipped with dry nitrogen blanketing and warm-water heating coils (never direct high-pressure steam).
- Mandatory Temperature and Dry-Blanketing Storage Rules:
  - Maintain storage temperature strictly between +18 °C and +30 °C (optimal +20 to +25 °C).
  - Freezing / Isomer Segregation Hazard (< +14 °C): Below +14 °C, TDI (Toluene Diisocyanate) T80/20 begins to freeze, selectively precipitating crystals of pure 2,4-TDI (mp 21.8 °C) and altering the 80:20 isomer ratio of the remaining liquid! If a drum or tank has cooled below +15 °C, warm the entire container in a 35 to 40 °C hot-air chamber until 100% liquid and homogenize thoroughly by rolling or recirculating before drawing any material.
  - Overheating / Dimerization Hazard (> +40 °C): Storing TDI (Toluene Diisocyanate) T80/20 above +40 °C accelerates self-addition into insoluble white uretdione dimer crystals (turbidity/sediment) and increases yellow color and vapor pressure.
  - Exclusion of Atmospheric Moisture: Always blanket bulk storage tanks and partially emptied drums with dry nitrogen gas (dew point <= -40 °C) or pad through silica-gel desiccant breathers; never allow humid air or water to contact TDI (Toluene Diisocyanate) T80/20.
  - Shelf Life: 6 to 12 months in original unopened nitrogen-blanketed steel drums stored at 18 to 30 °C.
- Transport Classification (ADR / RID / ADN / IMDG / IATA-DGR):
  - UN Number: UN 2078
  - Proper Shipping Name: TOLUENE DIISOCYANATE
  - Transport Hazard Class: Class 6.1 (Toxic Substances)
  - Packing Group: PG II (Medium Danger; Hazard Identification No. / Kemler Code: 60)

FIRST AID MEASURES AND SAFETY INFORMATION FOR TDI (TOLUENE DIISOCYANATE) T80/20

TDI (Toluene Diisocyanate) T80/20 is a highly reactive aromatic diisocyanate monomer that requires strict closed-system engineering controls and personal protective equipment in accordance with International Isocyanate Institute (III), EU REACH, and OSHA guidelines:
- GHS / EU CLP Hazard Classifications (Index No. 615-006-00-4):
  - Acute Toxicity Category 1 / Category 2 (Inhalation) — H330: Fatal if inhaled (Danger, skull & crossbones pictogram GHS06; 4-hour Rat Vapor/Aerosol LC50 ~ 0.10 to 0.48 mg/L; Rat Oral LD50 = 4,130 to 5,110 mg/kg bw; Rabbit Dermal LD50 > 9,400 mg/kg bw).
  - Respiratory Sensitizer Category 1 — H334: May cause allergy or asthma symptoms or breathing difficulties if inhaled (Health Hazard pictogram GHS08). Once an individual becomes immunologically sensitized to TDI (even at parts-per-billion concentrations), any subsequent inhalation exposure to even trace < 1 ppb TDI vapor can trigger severe, potentially life-threatening bronchospasm and occupational asthma!
  - Skin Sensitizer Category 1 — H317: May cause an allergic skin reaction.
  - Skin Irritation Category 2 (H315), Eye Irritation Category 2 (H319), and Specific Target Organ Toxicity — Single Exposure Category 3 (H335: May cause respiratory irritation).
  - Carcinogenicity Category 2 — H351: Suspected of causing cancer (classified based on high-dose gavage animal studies where TDI hydrolyzes in the stomach to TDA; inhalation studies have not demonstrated carcinogenicity in humans).
  - Aquatic Chronic Category 3 — H412: Harmful to aquatic life with long lasting effects.
- Occupational Exposure Limits (OEL / TLV / PEL) and Odor Threshold Warning:
  - ACGIH TLV (2024): 0.001 ppm (1 ppb = 0.007 mg/m3) 8-hour TWA; 0.005 ppm (5 ppb = 0.036 mg/m3) 15-minute STEL.
  - EU / UK WEL / German TRGS 900: 0.005 ppm (5 ppb = 0.035 mg/m3) 8-hour TWA; 0.010 ppm to 0.020 ppm ceiling/STEL.
  - US OSHA PEL: 0.02 ppm (20 ppb = 0.14 mg/m3) Ceiling limit.
  - CRITICAL SAFETY FACT: The human odor threshold for TDI (Toluene Diisocyanate) T80/20 is approximately 0.05 to 0.40 ppm (50 to 400 ppb)—which is 10 to 100 times HIGHER than the safe occupational exposure limit (1 to 5 ppb)! Therefore, if you can smell TDI, the airborne concentration is already dangerously above the legal exposure limit! Continuous electronic paper-tape or electrochemical isocyanate gas monitors must be installed in unloading, metering, and foam-tunnel areas.

- Mandatory EU REACH Restriction Entry 74 (Training Requirement for Industrial Users):
  - Under Commission Regulation (EU) 2020/1149 (REACH Annex XVII Entry 74), as of August 24, 2023, all industrial and professional workers handling diisocyanates (including TDI (Toluene Diisocyanate) T80/20 at concentrations >= 0.1% w/w) must complete certified safe-handling training prior to use.
- Personal Protective Equipment (PPE) & Spill Neutralization Protocol:
  - Respiratory Protection: For closed-loop sampling, drum connection, or maintenance where vapor may exceed the OEL, wear a positive-pressure supplied-air respirator or Self-Contained Breathing Apparatus (SCBA), or for short-duration low-level tasks a full-face respirator with organic vapor + particulate cartridges (EN 14387 Type A2-P3 / ABEK2-P3 with end-of-service-life protocol).
  - Eye & Skin Protection: Chemical splash goggles + full face shield (EN 166), chemical-resistant butyl rubber, Viton (FKM), or laminated PE/EVAL gloves (EN 374; change nitrile gloves immediately if splashed), and impervious chemical suit/apron.
  - Liquid Spill Neutralization Solution ("Decon Solution"): Never seal up wet TDI waste in a closed drum! Absorb spills with wet sand, vermiculite, or mineral absorbent (never sawdust) and neutralize immediately by pouring on an Alkaline Isocyanate Neutralization Solution consisting of: 90% to 92% Water + 5% to 8% Concentrated Aqueous Ammonia (or 5%–10% Sodium Carbonate Na2CO3) + 2% Liquid Detergent Surfactant (or alternatively 50% Water + 45% Isopropanol/Ethanol/Butoxyethanol + 5% Ammonia). Leave in an open, vented container for 24 to 48 hours to allow CO2 gas to escape completely as TDI converts into inert solid polyurea.

- First Aid Measures:
  - Inhalation: IMMEDIATELY move the affected person to fresh air, keep warm and at rest in a half-upright position, and seek immediate medical attention. Note to Physician: Respiratory sensitization and delayed bronchospasm or pulmonary edema may occur up to 24 to 48 hours after exposure; keep under medical observation for 48 hours.
  - Eye Contact: Immediately flush eyes with copious amounts of lukewarm running water for at least 15 to 20 minutes while holding eyelids wide open; transport immediately to an ophthalmologist.
  - Skin Contact: Immediately remove contaminated clothing, wipe off excess liquid TDI with dry cloth or polyethylene glycol (PEG 400) / corn oil if available, and wash skin thoroughly with plenty of soap and flowing water for 15 minutes.
  - Ingestion: Do NOT induce vomiting! Rinse mouth with water, keep the patient at rest, and seek immediate emergency medical care.

WHAT SHOULD BE CONSIDERED WHEN PURCHASING TDI (TOLUENE DIISOCYANATE) T80/20?

When purchasing TDI (Toluene Diisocyanate) T80/20 for flexible polyether slabstock, HR molded seating, or CASE prepolymer production, verify on the batch Certificate of Analysis that the 2,4-TDI / 2,6-TDI Isomer Ratio is strictly within 80.0 +/- 1.0% : 20.0 +/- 1.0% and Total TDI Assay is >= 99.5% w/w, ensuring predictable blow-to-gel kinetics and a wide stannous octoate processing window.
Buyers sourcing TDI (Toluene Diisocyanate) T80/20 should specify whether their process requires ASTM D1786 Type I Grade (Acidity <= 0.004% / 40 ppm, Hydrolyzable Chlorine <= 0.005%–0.010%, Color <= 15 APHA, ideal for polyether slabstock, HR molded foams, and low-color CASE prepolymers) or Type II Grade (controlled acidity 40–110 ppm for specialized ester foams).

During winter procurement and logistics (November through March), confirm that the supplier ships TDI (Toluene Diisocyanate) T80/20 in temperature-controlled storage or insulated ISO tanks maintained above +18 °C, and inspect incoming drums for any signs of partial freezing (< +14 °C) so that isomer segregation never enters the foaming mixhead.
Ensure that your facility's unloading pumps (magnetic-drive seal-less pumps recommended), dry-disconnect couplings, dry-nitrogen blanketing system (dew point <= -40 °C), exhaust scrubbers, and alkaline spill-neutralization kits are in place before receiving bulk or drum shipments of TDI (Toluene Diisocyanate) T80/20.
Finally, verify that the supplier provides full UN 2078 Class 6.1 dangerous-goods transport documentation, EU REACH / KKDIK registration compliance, and freshly manufactured nitrogen-blanketed drums with clear production and expiration dates.

TDI (TOLUENE DIISOCYANATE) T80/20 SUPPLY FROM ATAMAN KİMYA

Ataman Kimya supplies world-class, high-purity ASTM D1786 Type I / ISO 14896 compliant TDI (Toluene Diisocyanate) T80/20 (CAS 26471-62-5, EC 247-722-4, 80.0 +/- 1.0% 2,4-TDI and 20.0 +/- 1.0% 2,6-TDI, assay >= 99.5% w/w, NCO content 48.0%–48.25% w/w, color <= 15 APHA, hydrolyzable chlorine <= 0.005%–0.010%) in 250 kg nitrogen-sealed steel drums and bulk temperature-controlled ISO tank containers.
Every shipment of TDI (Toluene Diisocyanate) T80/20 from Ataman Kimya is stored in temperature-regulated warehouse facilities (+18 to +28 °C) to prevent winter crystallization or summer dimerization, and is delivered with a lot-specific Certificate of Analysis (CoA), EU CLP / Turkish KKDIK Safety Data Sheet (SDS), and certified ADR Class 6.1 (UN 2078) hazardous-materials transport.

For flexible slabstock mattress, furniture, and automotive molded foam manufacturers, Ataman Kimya offers a complete one-stop polyurethane portfolio alongside TDI (Toluene Diisocyanate) T80/20—including conventional and HR polyether polyols, graft copolymer polyols (POP), polymeric MDI, flame retardants (TCPP, TBEP, TEP), silicone surfactants, tertiary amine catalysts (BDMAEE, TEDA, DMCHA), Stannous Octoate (T-9), Diethanolamine (DEOA), and Methylene Chloride / auxiliary blowing agents.
For CASE (Coating, Adhesive, Sealant, and Elastomer) formulators, Ataman Kimya supplies TDI (Toluene Diisocyanate) T80/20 together with PTMEG, PPG diols/triols, Trimethylolpropane (TMP), MOCA / DMTDA curatives, DBTDL catalyst, and urethane-grade anhydrous solvents (Ethyl Acetate, Butyl Acetate, PMA, MEK).
Ataman Kimya's technical specialists support polyurethane processors with stoichiometric formulation guidance, safe-handling documentation, and reliable just-in-time logistics across Türkiye, Europe, the Middle East, Central Asia, and North Africa.

FREQUENTLY ASKED QUESTIONS ABOUT TDI (TOLUENE DIISOCYANATE) T80/20

 What does "T80/20" mean in TDI (Toluene Diisocyanate) T80/20, and why are three CAS numbers listed on technical data sheets?
"T80/20" indicates that the product is a precisely controlled isomer mixture containing 80.0 +/- 1.0% by weight of 2,4-Toluene Diisocyanate (CAS 584-84-9, EC 209-544-5) and 20.0 +/- 1.0% by weight of 2,6-Toluene Diisocyanate (CAS 91-08-7, EC 202-039-0). The commercial mixed-isomer product itself is registered globally under CAS 26471-62-5 (EC 247-722-4).

 Why is the 80:20 isomer ratio of TDI (Toluene Diisocyanate) T80/20 so important for flexible polyurethane foam production?
In 2,4-TDI (80%), the para-NCO group at position C-4 is sterically unhindered and reacts 4 to 8 times faster than the ortho-NCO group at C-2, providing rapid initial chain extension and gas retention during foam rise. In 2,6-TDI (20%), both NCO groups are sterically hindered at ortho positions C-2 and C-6, delaying final crosslinking until the internal bun exotherm reaches 110–155 °C and forming symmetric, crystalline polyurea hard segments that give the foam high load-bearing strength and prevent collapse.

 What happens if a drum of TDI (Toluene Diisocyanate) T80/20 cools below +14 °C in winter, and how must it be recovered?
Below +14 °C, TDI (Toluene Diisocyanate) T80/20 begins to freeze selectively: the higher-melting 2,4-TDI isomer (melting point +21.8 °C) crystallizes out first on the walls and bottom of the drum, leaving the remaining liquid enriched in 2,6-TDI! Drawing liquid from a partially frozen drum ruins foam production. To recover a partially frozen drum, warm the entire closed drum in a 35 to 40 °C hot-air room until 100% of the crystals have melted, and then roll or circulate the drum thoroughly to restore the homogeneous 80:20 isomer ratio before use.

 How do you calculate the exact parts per hundred polyol (phr) of TDI (Toluene Diisocyanate) T80/20 needed for a flexible foam recipe?
Because TDI (Toluene Diisocyanate) T80/20 has a molecular weight of 174.16 g/mol and a functionality of 2.00, its equivalent weight is 87.08 g/eq (48.23% NCO). At 100 Isocyanate Index, 1.00 phr of Water requires 9.667 phr of TDI (Toluene Diisocyanate) T80/20, and 100 phr of Polyol requires (0.1552 x Polyol OHv) phr of TDI. Multiply the sum of all active-hydrogen equivalents by (Target Index / 100) to obtain the exact TDI dosage.

 What is the difference between ASTM D1786 Type I and Type II TDI (Toluene Diisocyanate) T80/20?
Both Type I and Type II have >= 99.5% TDI purity and an 80.0 +/- 1.0% : 20.0 +/- 1.0% isomer ratio. Type I has ultra-low acidity (<= 0.004% as HCl) and ultra-low hydrolyzable chlorine (<= 0.005%–0.010%), making it the universal choice for polyether slabstock, HR molded foams, and CASE prepolymers. Type II has a slightly higher controlled acidity (0.004% to 0.011% as HCl) used in certain traditional polyester slabstock foams to widen the catalyst window.

 Why must water never enter a closed storage drum or tank of TDI (Toluene Diisocyanate) T80/20?
Water reacts exothermically with TDI (Toluene Diisocyanate) T80/20 to form solid insoluble polyurea crusts (which clog pumps, filters, and high-pressure mixheads) while liberating carbon dioxide (CO2) gas. In a tightly sealed drum or unvented pipe, the evolved CO2 gas creates dangerous internal overpressure that can bulge or rupture the container.

 Why can't workers rely on smell to detect TDI (Toluene Diisocyanate) T80/20 vapor in the workplace?
The occupational exposure limit (TLV-TWA) for TDI (Toluene Diisocyanate) T80/20 is extremely low—1 to 5 parts per billion (0.001 to 0.005 ppm)—whereas the human nose cannot smell TDI until concentrations reach 50 to 400 parts per billion (0.05 to 0.40 ppm). Therefore, if TDI odor is noticeable, the airborne concentration is already far above safe limits, requiring continuous electronic gas monitoring and local exhaust ventilation.

 How should a liquid spill of TDI (Toluene Diisocyanate) T80/20 be neutralized and cleaned up?
Wearing full PPE and respiratory protection, contain the spill with wet sand or mineral absorbent (never dry sawdust) and treat it with an alkaline decontamination solution (90% water + 5%–8% aqueous ammonia or sodium carbonate + 2% liquid detergent surfactant). Collect the treated material into an open-top or vented waste drum for 24 to 48 hours until CO2 evolution ceases and the TDI is completely converted into inert solid polyurea.

 Why do coatings and foams made from TDI (Toluene Diisocyanate) T80/20 turn yellow when exposed to sunlight?
Because TDI (Toluene Diisocyanate) T80/20 is an aromatic diisocyanate, UV light photo-oxidizes the aromatic urethane/urea linkages into conjugated quinone-imide structures that absorb blue light and appear yellow. This yellowing is purely cosmetic and does not degrade the mechanical cushioning or adhesive strength of indoor mattresses, car seats, wood primers, or packaging adhesives; for outdoor UV-exposed topcoats, aliphatic isocyanates (HDI/IPDI) are used over TDI primers.

 What is the UN number and transport hazard class of TDI (Toluene Diisocyanate) T80/20?
TDI (Toluene Diisocyanate) T80/20 is transported under UN 2078, Proper Shipping Name: TOLUENE DIISOCYANATE, Hazard Class 6.1 (Toxic Substances), Packing Group II across ADR, RID, IMDG, and IATA regulations.

TDI (TOLUENE DIISOCYANATE) T80/20 – TECHNICAL SUMMARY

TDI (Toluene Diisocyanate) T80/20 (Toluene Diisocyanate 80/20, 80% 2,4-TDI CAS 584-84-9 and 20% 2,6-TDI CAS 91-08-7, mixed-isomer CAS 26471-62-5, EC 247-722-4, C9H6N2O2, MW 174.16 g/mol, eq wt 87.08 g/eq) is the global benchmark monomeric aromatic diisocyanate for flexible polyurethane foams and reactive CASE prepolymers. Combining a high 48.2% w/w isocyanate content, water-white clarity (<= 15 APHA), low viscosity (~2.4 mPa·s at 25 °C), and a regioselective 80:20 isomer ratio that synchronizes fast para-NCO chain extension with high-temperature ortho-NCO network completion, TDI (Toluene Diisocyanate) T80/20 is indispensable across flexible polyether/polyester slabstock mattress and furniture foams, HR automotive molded seating, PTMEG/PPG cast elastomers, TDI-TMP coating/adhesive hardeners, and moisture-cure polyurethane sealants. For technical specifications, lot-specific CoA/SDS documentation, or drum and ISO-tank quotations for TDI (Toluene Diisocyanate) T80/20, contact Ataman Kimya:

Ataman Chemicals
Phone: +90 216 577 10 10
Email: info@atamankimya.com