Trade Name:PPDI
Similar Name::1,4-Phenylene diisocyanate (PPDI), P-Phenylene Didisocyanate, Paraphenylene diisocyanate, Benzene 1,4-diisocyanate
Molecular Formula:C8H4N2O2
CAS Number:104-49-4

HARTDUR 120 (PPDI) is pure 1,4-Phenylene diisocyanate (PPDI), CAS number is 104-49-4. PPDI is an advanced curing agent / chain extenders for polyurethane (PU) thermoplastic elastomers. PPDI-based casting elastomers are featured with excellent dynamic performance. The obvious advantage is that high-speed wheels produced with PPDI can stands for much higher temperature under rapid and continuous operation/movement. Thus, PPDI-based wheels are an ideal solution for those needs long running life, big loading capacity and high heat resistance demands. In general, PU elastomers characterized with excellent abrasion, tear and cut resistance comparing to synthetic rubbers. Despite PPDI and MDI have similar formulation, hardness and modulus properties compared to TODI, the isocyanate has a lower molar ratio of polyol to polyol in PPDI. Basically, the PPDI-type elastomers are more flexible than traditional MDI-type and TODI-type polyurethane elastomers. Among all the polyurethane elastomers, PPDI-based ones are known for the extremely stressed wheels, i.e. tires for forklifts, vehicles and airplanes; guide rollers, wheels for machines; high speed skate rollers and so on. In short, PPDI-type elastomer is the ideal choice for applications of Lowest abrasion and Highest temperature. Nowadays, PPDI curing agent is widely used in TPU-products as main chain extender, and the application keeps expanding, including O-rings, hydraulic seals, coupling stars and screen printing squeegee blades.


20kg, 40kg/iron drum.

It can be packaged on demand. Please inquire.      

HARTDUR 120 (PPDI / 1,4-Phenylene diisocyanate) is supplied in the form of yellowish white to white, crystalline flakes or powder. Its vapor pressure at room temperature is below 10-4mbar. Permissible in the air at working places according to the Federal Republic of Germany is 0.01 ppm = 0.087 mg/m3. This value is not allowed to exceed even for short periods. Being exceptionally reactive, PPDI must be treated as a dangerous material and it must therefore be handled with care. The potential risks of HARTDUR 120 (PPDI) depend mainly on the extent to which isocyanate dust, vapors, or aerosols are formed during the processing of this product. The circumstances and operations in which workers may be exposed to HARTDUR 120 (PPDI) in any of these forms are as follows: dust may rise from the solid material while it is being weighed or introduced into reaction vessels; vapors and aerosols are formed in the cross linking of hot prepolymer batches containing an excess of PPDI and in the production of castings (the aerosols owe their formation to the cooling and condensation of hot isocyanate vapors).

Chemical composition1,4-Phenylene diisocyanate (PPDI), P-Phenylene Didisocyanate, Paraphenylene diisocyanate, Benzene 1,4-diisocyanate
Molecular formulaC8H4N2O2
Molecular weight160.1296
NCO %52.5%
Odor Characteristiccyanate odor
Purity≥ 99.0%
Density1.17g//cm3 at 20°C
Boiling point236.2°C at 760 mmHg
Freezing point96-99°C
Flash point92.4°C
Vapor pressure0.048mmHg at 25°C
Total chlorine≤ 0.1%
Hydrolysable chlorine≤ 0.03%
Melting point94°C


Caution: HARTDUR 120 (PPDI) is very sensitive to moisture. Water reacts with all diisocyanates to form insoluble urea derivatives. HARTDUR 118(TODI) should be stored in tightly sealed containers in cool and dry conditions. Do not put PPDI along with food and avoid exposing in an environment above 30℃. After using, the lid must be sealed immediately in case of dysfunction. Under suitable external conditions, PPDI is valid for six months at least with effect from the date on which it’s delivered.


Benefits for its extraordinary advantages of heat, abrasion, tear and cut resistance, PPDI-based elastomers are widely applied on industries which require for hardly deformation, heat-durable functions. PPDI is the key player in TPU (thermoplastic polyurethane elastomer). Hydraulic seals, wipers, piston seals, O-rings, rod seals, pulleys which requested for heat resistance and pressure resistance are other important fields of PPDI curing agent. Not mention tires for forklifts, vehicles, machines, airplanes and pulleys, wheels, guide rollers for dampening elements which are the other category for PPDI-type elastomers.