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Isophthaloyl Chloride (ICL)

m-Phthaloyl Chloride

Product Description and Uses

ICL is a difunctional acid chloride used in a variety of performance polymers and fibers, where it is valued for flame resistance, temperature stability, chemical resistance, and flexibility. In addition, it is an effective stabilizer for urethane prepolymers due to its ability to scavenge water.

ICL is a clear water-white liquid above its freezing point and a white crystalline solid at room temperature. Mixes of isophthaloyl chloride (ICL) and terephthaloyl chloride (TCL) are available on request. DuPont offers ICL in cast form in drums and in tank trucks and isotanks as a molten liquid. ICL is soluble in methylene chloride and other organic solvents.


Specifications and other information on ICL are easily obtained by contacting us.

Typical Physical Properties*

Property  Typical Value

Molecular Weight 

Boiling Point (760 mmHg), °C (°F)   269 (516) 
Melting Point Range, °C (°F)   42-44 (107-111) 
Specific Gravity, 50°C (122°F)  1.388   
Vapor Pressure (mmHg) @ 25°C (77°F), solid  0.03   
Vapor Pressure (mmHg) @ 37.7°C (99.9°F), solid  0.06   
 Vapor Pressure (mmHg) @ 100°C (212°F)  1.4  
Vapor Pressure (mmHg) @ 200°C (392°F)   110 
Flash Point, Cleveland Open Cup, °C (°F)     156 (313) 














*These properties are drawn from various DuPont and other literature sources. DuPont does not make any warranty, express or implied, that future production will demonstrate these typical properties.

Shipping Information

ICL is available in cast form in steel drums and as a molten liquid in tank trucks and ISO tanks.