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Chemical Datasheet

ISOPHTHALIC ACID

Chemical Identifiers

CAS Number UN/NA Number DOT Hazard Label USCG CHRIS Code
  • 121-91-5
none data unavailable
  • IPL
NIOSH Pocket Guide International Chem Safety Card
none
  • ISOPHTHALIC ACID
NFPA 704
data unavailable
General Description
White solid with a slight unpleasant odor. Sinks in water. (USCG, 1999)

Hazards

Reactivity Alerts
none
Air & Water Reactions
Dust forms explosive mixture in air (USCG, 1999).
Fire Hazard
Behavior in Fire: Dust forms explosive mixture in air. (USCG, 1999)
Health Hazard
May cause slight to moderate irritation of eyes, skin, and mucous membranes on prolonged contact. Ingestion may cause gastrointestinal irritation. (USCG, 1999)
Reactivity Profile
ISOPHTHALIC ACID is a carboxylic acid. Carboxylic acids donate hydrogen ions if a base is present to accept them. They react in this way with all bases, both organic (for example, the amines) and inorganic. Their reactions with bases, called "neutralizations", are accompanied by the evolution of substantial amounts of heat. Neutralization between an acid and a base produces water plus a salt. Carboxylic acids with six or fewer carbon atoms are freely or moderately soluble in water; those with more than six carbons are slightly soluble in water. Soluble carboxylic acid dissociate to an extent in water to yield hydrogen ions. The pH of solutions of carboxylic acids is therefore less than 7.0. Many insoluble carboxylic acids react rapidly with aqueous solutions containing a chemical base and dissolve as the neutralization generates a soluble salt. Carboxylic acids in aqueous solution and liquid or molten carboxylic acids can react with active metals to form gaseous hydrogen and a metal salt. Such reactions occur in principle for solid carboxylic acids as well, but are slow if the solid acid remains dry. Even "insoluble" carboxylic acids may absorb enough water from the air and dissolve sufficiently in it to corrode or dissolve iron, steel, and aluminum parts and containers. Carboxylic acids, like other acids, react with cyanide salts to generate gaseous hydrogen cyanide. The reaction is slower for dry, solid carboxylic acids. Insoluble carboxylic acids react with solutions of cyanides to cause the release of gaseous hydrogen cyanide. Flammable and/or toxic gases and heat are generated by the reaction of carboxylic acids with diazo compounds, dithiocarbamates, isocyanates, mercaptans, nitrides, and sulfides. Carboxylic acids, especially in aqueous solution, also react with sulfites, nitrites, thiosulfates (to give H2S and SO3), dithionites (SO2), to generate flammable and/or toxic gases and heat. Their reaction with carbonates and bicarbonates generates a harmless gas (carbon dioxide) but still heat. Like other organic compounds, carboxylic acids can be oxidized by strong oxidizing agents and reduced by strong reducing agents. These reactions generate heat. A wide variety of products is possible. Like other acids, carboxylic acids may initiate polymerization reactions; like other acids, they often catalyze (increase the rate of) chemical reactions.
Belongs to the Following Reactive Group(s)
Potentially Incompatible Absorbents

No information available.

Response Recommendations

Isolation and Evacuation
No information available.
Firefighting
Fire Extinguishing Agents: Water, dry powder, foam, carbon dioxide (USCG, 1999)
Non-Fire Response
No information available.
Protective Clothing
If without adequate ventilation, use respirator with dust filter, goggles, and gloves (USCG, 1999)
DuPont Tychem® Suit Fabrics
No information available.
First Aid
INHALATION: remove victim to uncontaminated area; get medical attention if complications arise.

INGESTION: get medical attention if complications arise.

EYES: flush with large amounts of water for 15 min.; get prompt medical attention.

SKIN: wash with water. (USCG, 1999)

Physical Properties

Chemical Formula:
  • C8H6O4
Flash Point: data unavailable
Lower Explosive Limit (LEL): data unavailable
Upper Explosive Limit (UEL): data unavailable
Autoignition Temperature: data unavailable
Melting Point: 653°F (USCG, 1999)
Vapor Pressure: data unavailable
Vapor Density (Relative to Air): data unavailable
Specific Gravity: 1.54 at 77°F (USCG, 1999) - Denser than water; will sink
Boiling Point: data unavailable
Molecular Weight: 166 (USCG, 1999)
Water Solubility: data unavailable
Ionization Energy/Potential: data unavailable
IDLH: data unavailable

AEGLs (Acute Exposure Guideline Levels)

No AEGL information available.

ERPGs (Emergency Response Planning Guidelines)

No ERPG information available.

PACs (Protective Action Criteria)

Chemical PAC-1 PAC-2 PAC-3
Isophthalic acid; (Phthalic acid, m isomer) (121-91-5) 30 mg/m3 340 mg/m3 2100 mg/m3
(DOE, 2018)

Regulatory Information

EPA Consolidated List of Lists

No regulatory information available.

CISA Chemical Facility Anti-Terrorism Standards (CFATS)

No regulatory information available.

OSHA Process Safety Management (PSM) Standard List

No regulatory information available.

Alternate Chemical Names