Isophthalsure
PIA · 1,3-BENZENEDICARBOXYLIC ACID · Isophthalic · isophthalate · 1,3-dicarboxybenzene · M-PHTHALIC ACID · 1,3-phthalicacid · Isophthalic acid 99%

Identifikatoren & physikalische Daten
| CAS No. | 121-91-5 |
|---|---|
| Summenformel | C8H6O4 |
| Durchschnittliche Molmasse | 166,13 g/mol |
| Monoisotopische Masse | 166,02660867 g/mol |
| SMILES | O=C(O)c1cccc(C(=O)O)c1 |
| InChIKey | QQVIHTHCMHWDBS-UHFFFAOYSA-N |
| PubChem CID | 8496 |
| ChEMBL | CHEMBL1871181 |
| ChEBI | CHEBI:30802 |
| EC No. | 204-506-4 |
| DTXSID | DTXSID3021485 |
| Lokaler Name | Isophthalsure |
Chemische & physikalische Eigenschaften
| XLogP | 1,7 |
|---|---|
| Polarare Oberfläche (TPSA) | 74,6 |
| H-Brücken-Donoren | 2 |
| H-Brücken-Akzeptoren | 4 |
| Frei drehbare Bindungen | 2 |
| Schwere Atome | 12 |
| Formalladung | 0 |
| Komplexität | 179 |
| LogP (Verteilungskoeffizient) | log Kow = 1.66 |
| Dichte | 1.54 at 77 °F (USCG, 1999) - Denser than waterwill sink1.53 at 4 °CDensity = 9.0710 kmol/cu m at 20 °CRelative density (water = 1): 1.541.507 @ 20°C1,54 g/cm3 |
| Viscosity | 0.00025186 Pa-s at 619.15K (346 °C) |
| Color/Form | Crystalline powderColorless crystalsNeedles from water or alcohol |
| Löslichkeit | Soluble in 8000 parts cold water, 460 parts boiling waterfreely soluble in alcoholpractically insoluble in petroleum etherIn methanol: 4.0 g/100 g at 25 °Cin propanol: 1.7 g/100 g at 25 °C, 2.7 g/100 g at 50 °Cin glacial acetic acid: 0.23 g/100 g at 25 °CInsoluble in benzene, ligroin and etherWater solubility: 120 mg/L at 25 °C, 350 mg/L at 50 °C, 3200 mg/L at 100 °CIn water, 5400 mg/L at 14 °C (pH adjusted water for complete dissociation)Solubility in water: none in cold water, poor in boiling water0.12g/l0.01 g/100 mL (25 ºC) |
| Siedepunkt | SublimesBoiling point = 753.00 K (Based on predicted value for phthalic acid by Meissner's method with a suitable adjustment for isomerism based on similar compound relationships.)214.32°C (rough estimate) |
| Decomposition | When heated to decomposition it emits acrid smoke and fumes. |
| Schmelzpunkt | 653 °F (USCG, 1999)347 °CTriple point temperature and pressure = 619.15 K (estimated to be equal to the melting point), 2.8020X10+3 PaMelting point = 619.15 K (determined in sealed tube)345-348 °C341-343 °C (lit.) |
| Dampfdruck | 0.00000002 [mmHg]VP: 0.009 Pa (0.0675 mm Hg) at 100 °C0.068 [mm Hg] @100 °C0Pa at 25℃ |
| Surface Tension | 0.048239 N/m at 346 °C |
| Heat of Vaporization | 1.0921X10+8 J/kmol at the melting point of 619.15 K (346 °C) |
| Physical Description | Isophthalic acid is a white solid with a slight unpleasant odor. Sinks in water. (USCG, 1999)Dry PowderOther SolidLarge CrystalsCBILiquidColorless solid[Hawley] Sublimes without decomposition[Merck Index] Melting point = 347 deg C[HSDB] Faintly beige powder[MSDSonline]COLOURLESS CRYSTALLINE POWDER. |
| Brechungsindex | 1.5100 (estimate) |
| Lagerbedingungen | Sealed in dry,Room Temperature |
| Aggregatzustand | Crystalline Powder |
| pKa (Säurekonstante) | 3.54(at 25℃) |
| Farbe | White to off-white |
| pH | 3.33(1 mM solution)2.76(10 mM solution)2.24(100 mM solution) |
| Merck | 14,5197 |
| BRN | 1909332 |
| Henry-Konstante | 4.0×109 mol/(m3Pa) at 25℃, Yaws (2003) |
| Dielektrizitätskonstante | 1.4(Ambient) |
| Stabilität | Stable. Incompatible with strong oxidizing agents, strong bases. |
| InChI | 1S/C8H6O4/c9-7(10)5-2-1-3-6(4-5)8(11)12/h1-4H,(H,9,10)(H,11,12) |
| InChIKey | QQVIHTHCMHWDBS-UHFFFAOYSA-N |
| SMILES | OC(=O)c1cccc(c1)C(O)=O |
| LogP (Verteilungskoeffizient) | 1.66 at 25℃ |
| CAS Datenbank | 121-91-5(CAS DataBase Reference) |
| NIST chemische Informationen | 1,3-Benzenedicarboxylic acid(121-91-5) |
| EPA chemische Informationen | Isophthalic acid (121-91-5) |
Sicherheit & Vorschriften
| GHS-Einstufung | This chemical does not meet GHS hazard criteria for 91% (614 of 675) of all reports.Not ClassifiedReported as not meeting GHS hazard criteria by 614 of 675 companies (only 9% companies provided GHS information). For more detailed information, please visit ECHA C&L website.Aggregated GHS information provided per 675 reports by companies from 9 notifications to the ECHA C&L Inventory.Reported as not meeting GHS hazard criteria per 614 of 675 reports by companies.There are 5 notifications provided by 61 of 675 reports by companies with hazard statement code(s).Information may vary between notifications depending on impurities, additives, and other factors. The percentage value in parenthesis indicates the notified classification ratio from companies that provide hazard codes. Only hazard codes with percentage values above 10% are shown. For more detailed information, please visit ECHA C&L website. |
|---|---|
| Regulatorische Informationen | Chemical: 1,3-Benzenedicarboxylic acid1,3-Benzenedicarboxylic acid is listed on the EPA's Chemical Data Reporting (CDR) system. Manufacturers and importers of 1,3-Benzenedicarboxylic acid are required to report information about their production and use of this chemical to the EPA under the Toxic Substances Control Act (TSCA). (40 eCFR Part 711)Status: Active Update: 15-02-2023 https://echa.europa.eu/registration-dossier/-/registered-dossier/15373Status: Cease Manufacture Update: 04-07-2012 https://echa.europa.eu/registration-dossier/-/registered-dossier/6788Isophthalic acid: Does not have an individual approval but may be used under an appropriate group standard |
| Weitere Sicherheitsinformationen | IMAP assessments - 1,3-Benzenedicarboxylic acid: Human health tier I assessment |
| Brandgefahren | Behavior in Fire: Dust forms explosive mixture in air. (USCG, 1999)Combustible. Finely dispersed particles form explosive mixtures in air. |
| Gesundheitsgefahren | May cause slight to moderate irritation of eyes, skin, and mucous membranes on prolonged contact. Ingestion may cause gastrointestinal irritation. (USCG, 1999) |
| Gefahrenübersicht | A mild skin irritant[ICSC] May cause irritation[MSDSonline] No evidence of eye or skin irritation in animal studiesCaused kidney stones in animals fed >400 mg/kg per day[AIHA] |
| FDA-Anforderungen | Isophthalic acid is an indirect food additive for use only as a component of adhesives. |
| Reaktive Gruppe | Acids, CarboxylicHydrocarbons, Aromatic |
| 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 waterthose 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 ( |
| Luftstandards | This action promulgates standards of performance for equipment leaks of Volatile Organic Compounds (VOC) in the Synthetic Organic Chemical Manufacturing Industry (SOCMI). The intended effect of these standards is to require all newly constructed, modified, and reconstructed SOCMI process units to use the best demonstrated system of continuous emission reduction for equipment leaks of VOC, considering costs, non air quality health and environmental impact and energy requirements. Isophthalic acid is produced, as an intermediate or a final product, by process units covered under this subpart. |
| Physical Dangers | Dust explosion possible if in powder or granular form, mixed with air. |
| Air and Water Reactions | Dust forms explosive mixture in air (USCG, 1999). |
| Hazard Classes and Categories | Not Classified |
| Brandbekämpfung | Fire Extinguishing Agents: Water, dry powder, foam, carbon dioxide (USCG, 1999)Use water spray, foam, powder, carbon dioxide. |
| Erste-Hilfe-Maßnahmen | Fresh air, rest.Remove contaminated clothes. Rinse skin with plenty of water or shower.First rinse with plenty of water for several minutes (remove contact lenses if easily possible), then refer for medical attention.Rinse mouth. |
| Erste Hilfe | INHALATION: remove victim to uncontaminated areaget 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) |
| Expositionsschutz und Persönliche Schutzausrüstung | 5.0 [mg/m3], inhalable fraction[German Research Foundation (DFG)] |
| Entsorgungsverfahren | SRP: The most favorable course of action is to use an alternative chemical product with less inherent propensity for occupational harm/injury/toxicity or environmental contamination. Recycle any unused portion of the material for its approved use or return it to the manufacturer or supplier. Ultimate disposal of the chemical must consider: the material's impact on air qualitypotential migration in soil or watereffects on animal and plant lifeand conformance with environmental and public health regulations. |
| Verschüttetes entsorgen | Personal protection: particulate filter respirator adapted to the airborne concentration of the substance. Sweep spilled substance into covered containers. If appropriate, moisten first to prevent dusting. Carefully collect remainder. Then store and dispose of according to local regulations. |
| Preventive Measures | SRP: The scientific literature for the use of contact lenses by industrial workers is inconsistent. The benefits or detrimental effects of wearing contact lenses depend not only upon the substance, but also on factors including the form of the substance, characteristics and duration of the exposure, the uses of other eye protection equipment, and the hygiene of the lenses. However, there may be individual substances whose irritating or corrosive properties are such that the wearing of contact lenses would be harmful to the eye. In those specific cases, contact lenses should not be worn. In any event, the usual eye protection equipment should be worn even when contact lenses are in place. |
| Eye Prevention | Wear safety spectacles. |
| Fire Prevention | NO open flames. Closed system, dust explosion-proof electrical equipment and lighting. Prevent deposition of dust. |
| Inhalation Risk | Evaporation at 20 °C is negligiblea nuisance-causing concentration of airborne particles can, however, be reached quickly. |
| Skin Prevention | Protective gloves. |
| Exposure Prevention | PREVENT DISPERSION OF DUST! |
| Umweltverhalten | TERRESTRIAL FATE: Based on a recommended classification scheme(1), an estimated Koc value of 79(SRC), derived from a molecular structure estimation method(2), suggests that isophthalic acid will have high mobility in soil(SRC). It is a dibasic (2 displaceable hydrogen atoms) acid whose pKa1 is 3.70 and pKa2 is 4.60 at 25 °C(3) and will primarily exist in the anion form in the environment and form salts with cations in soilanions generally do not adsorb more strongly to soils containing organic carbon and clay than their neutral counterparts(4). Volatilization of isophthalic acid from moist soil surfaces is not expected to be an important fate process(SRC) given an estimated Henry's Law constant of 2.2X10-12 atm-cu m/mole(SRC), using a fragment constant estimation method(5). It absorbs UV radiation >290 nm(6), and therefore may degrade by direct photolysis on the soil surface(SRC). Isophthalic acid is readily biodegradable in screening tests using sewage sludge(7-10) and may be expected to biodegrade in soil(8).AQUATIC FATE: Based on a classification scheme(1), an estimated Koc value of 79(SRC), determined from a structure estimation method(2), indicates that isophthalic acid is not expected to adsorb to suspended solids and sediment(SRC). Volatilization from water surfaces is not expected(3) based upon an estimated Henry's Law constant of 2.2X10-12 atm-cu m/mole(SRC), developed using a fragment constant estimation method(4). Isophthalic acid is a dibasic (2 displaceable hydrogen atoms) acid whose pKa1 is 3.70 and pKa2 is 4.60 at 25 °C(5) and will be largely dissociated in at an environmental pH range of pH 5 to pH 9(SRC). According to a classification scheme(6), an estimated BCF of 3(SRC), from an estimated log Kow of 1.66(7) and a regression-derived equation(8), suggests the potential for bioconcentration in aquatic organisms is low. Isophthalic acid absorbs UV radiation >290 nm(9), and therefore may be susceptible to direct photolysis in surface waters(SRC). Isophthalic acid is not expected to undergo hydrolysis in the environment due to the lack of functional groups that hydrolyze under environmental conditions(3). Isophthalic acid has been shown to be readily biodegradable in screening studies(10-13) and is expected to biodegrade in natural water(11).ATMOSPHERIC FATE: According to a theory of gas/particle partitioning of semivolatile organic compounds in the atmosphere(1), isophthalic acid, which has an estimated vapor pressure of 2.6X10-8 mm Hg at 25 °C(SRC), determined from a fragment constant method(2), will exist in both the vapor and particulate phases in the ambient atmosphere. Its existence in the atmosphere in both phases has been observed experimentally(3,4). Vapor-phase isophthalic acid is degraded in the atmosphere by reaction with photochemically-produced hydroxyl radicals(SRC)the half-life for this reaction in air is estimated to be 12 days(SRC), calculated from its rate constant of 1.3X10-12 cu cm/molecule-sec at 25 °C(SRC) that was derived using a structure estimation method(5). Particulate-phase isophthalic acid may be physically removed from the air by wet and dry deposition(SRC). Isophthalic acid absorbs at wavelengths >290 nm(6), and therefore may be susceptible to direct photolysis by sunlight(SRC). |
| Expositionspfade | The substance can be absorbed into the body by ingestion. |
| Ökotoxizitätsauszüge | /AQUATIC SPECIES/ No signs of toxicity were observed in Leuciscus idus melanotus (Golden orfe) exposed to IPA at levels of up to 895 mg/L (measured) for 96 hours under static conditions./AQUATIC SPECIES/ No signs of toxicity in terms of mortality or immobilization were observed in Daphnia magna (water flea) exposed to IPA at levels of up to 876 mg/L (measured) for 48 hours under static conditions./AQUATIC SPECIES/ No adverse effects on growth were observed in Scenedesmus subspicatus (green algae) exposed to IPA at levels of up to 969 mg/L (measured) for 96 hours under static conditions./AQUATIC SPECIES/ In activated sewage sludge, toxicity to bacteria, as indicated by inhibition of oxygen consumption, was evident with a EC50 value of 617 mg/L. |
| Signs and Symptoms | Redness. |
| Effluent Concentrations | The fine particle emission rate of isophthalic acid from a boiler burning No. 2 distillate fuel oil was 217.4-243.4 pg/kJ(1). The concentration of isophthalic acid in smoke particles collected from the open burning of plastic bags, roadside litter and landfill trash was 2.8, 35.4 and 4.8 ng/mg respectively(2). |
| Soil Adsorption/Mobility | Using a structure estimation method based on molecular connectivity indices(1), the Koc of isophthalic acid can be estimated to be 79(SRC). According to a classification scheme(2), this estimated Koc value suggests that isophthalic acid is expected to have high mobility in soil(SRC). Isophthalic acid is a dibasic (2 displaceable hydrogen atoms) acid whose pKa1 is 3.70 and pKa2 is 4.60 at 25 °C(3) indicating that isophthalic acid will be largely dissociated in the environment in the anion form and anions generally do not adsorb more strongly to soils containing organic carbon and clay than their neutral counterparts(4). |
| Natural Pollution Sources | Isophthalic acid was an oxidation product of Singletary Lake (a freshwater lake in eastern North Carolina) fulvic acid(1). |
| Atmospheric Concentrations | URBAN/SUBURBAN: Isophthalic acid was detected, but not quantified, in the gas phase of urban air in Belgium(1). It was identified in airborne particulate matter (prominent GC peak) from a suburban area 60 km northeast of Tokyo, Japan in April 1985(2). The ambient annual average concentration of isophthalic acid in fine particle organic compounds at four sites on a west to east trajectory, West Los Angeles, downtown Los Angeles, Pasadena, and Rubidouc for 1982 were 2.1, 3.4, 2.9 and 2.1 ng/cu m, respectively(3)24-hr samples were collected at 6 day intervals throughout the yearthe concentration of isophthalic acid at a background site on San Nicolas Island, west of Los Angeles, averaged <0.03 ng/cu m from July to December(3). A study was performed of the long-term transport of photochemical air pollution from coastal areas in Japan with large emission sources to inland mountains(4)the resulting mean concentration of isophthalic acid in airborne aerosols in a plume at Takasaki (July 26-31, 1986) and Karuizawa (July 29-31, 1986) was 2.2 and 1.3 ng/cu m, respectively(4). The ratio of carboxylic acids to acetylene (which is believed to be derived from the same sources) increased during the day and decreased at night and averaged 72% at Takasaki and 84% at Karuizawa, suggesting that isophthalic acid is almost entirely formed photochemically during long-term transport(4). Airborne particulate matter (PM2.5 fraction) collected from eight sites in the southeastern US in 1999 and 2000 contained isophthalic acid concentrations ranging from 0.21 to 0.73 ng/cu m(5). Samples of atmospheric particulate matter collected at 12 sites in southern California in 1995 were found to contain average isophthalic acid concentration ranges of 0.233 to 0.616 ng/cu m(6). The concentration of isophthalic acid in the particulate matter of air samples collected at Fresno and Bakersfield CA (Dec 26, 1995 to Jan 6, 1996) ranged from 1.89 to 3.41 ng/cu m(7).RURAL/REMOTE: The concentration of isophthalic acid in the particulate matter of air samples collected at the Kern Wildlife refuge in CA (Dec 26, 1995 to Jan 6, 1996) ranged from 0.349 to 0.433 ng/cu m(1).SOURCE DOMINATED: The isophthalic acid concentration in the particulate-phase of air collected from a roadway tunnel in California was 157.5 ug/L(1). An isophthalic acid concentration range of 28.4 to 107 ng/cu m was detected in air samples (PM2.5 particulates) collected inside the Shing Mun tunnel in Hong Kong between Aug 13, 2003 to Feb 25, 2004(2). |
| Artificial Pollution Sources | Isophthalic acid's production and use as a raw material in the production of unsaturated polyester resins, alkyd coatings, other polymers and derivative chemicals(1) may result in its release to the environment through various waste streams(SRC). There are industrially important esters of isophthalic acid such as dimethyl isophthalate that may undergo chemical or enzymatic hydrolysis to yield isophthalic acid(2,3). |
| Environmental Biodegradation | AEROBIC: Isophthalic acid, present at 100 mg/L, reached 78 of its theoretical BOD in 2 weeks using an activated sludge inoculum at 30 mg/L in the Japanese MITI test indicating ready biodegradability(1). Under aerobic conditions and following OECD guideline 301B, approximately 9%, 46%, 64%, and 77% of isophthalic acid contained in sludge was degraded after 2, 5, 7, and 12 days, respectively(2). Isophthalic acid is degraded by aerobic microorganisms isolated from soil and marine sediment(3,4)cultures isolated from marine cultures also degraded isophthalic acid under anaerobic conditions(4). After an acclimation to an activated sludge inoculum over a 24 day period, 84% of isophthalate was consumed in a respiratory test(5). Isophthalic acid completely degraded in 8 days in a biodegradation test that used a soil inoculum(6). In another screening test, 95% of COD was removed in 5 days using an acclimated activated sludge inoculum(7). In anaerobic biodegradation tests using granular and digested sewage sludge inoculum, isophthalic acid (as isophthalate) could be completely mineralized with a lag phase for 50% degradation ranging from 74 to 156 days(8). Using bacteria from river water as inocula (Songhua River, China) and a sealed-bottled method, isophthalic acid was found to be readily biodegradable with first-order rate constant of 1.43/day(9). |
| Environmental Bioconcentration | An estimated BCF of 3 was calculated in fish for isophthalic acid(SRC), using a log Kow of 1.66(1) and a regression-derived equation(2). According to a classification scheme(3), this BCF suggests the potential for bioconcentration in aquatic organisms is low. |
| Volatilization from Water/Soil | The Henry's Law constant for isophthalic acid is estimated as 2.2X10-12 atm-cu m/mole(SRC) using a fragment constant estimation method(1). This Henry's Law constant indicates that isophthalic acid is expected to be essentially nonvolatile from water surfaces(2). Isophthalic acid's Henry's Law constant indicates that volatilization from moist soil surfaces is not expected to occur(SRC). Isophthalic acid is not expected to volatilize from dry soil surfaces(SRC) based upon a vapor pressure of 0.0675 mm Hg at 100 °C(3). |
| Wassergefährdungsklasse (WGK) | 2 |
| TSCA-Inventar-Status | TSCA listed |
| Zollcode | 29173980 |
| RTECS-Nr. | NT2007000 |
| R-Sätze (R) | 36/37/38 |
| Gefahrensymbole | Xi |
| Sicherheitshinweise (S) | 24/25-36-26 |
| Lagerklasse | 13 - Non Combustible Solids |
| Gefahrstoffdaten | 121-91-5(Hazardous Substances Data) |
| Selbstentzündungstemperatur | 1198 °F |
Anwendungen & Verwendung
Beschreibung
Isophthalic acid is an organic compound with the formula C6H4(CO2H)2. This colourless solid is an isomer of phthalic acid and terephthalic acid. These aromatic dicarboxylic acids are used as precursors (in form of acyl chlorides) to commercially important polymers, e.g. the fire-resistant material Nomex. Mixed with terephthalic acid, iso phthalic acid is used in the production of resins for drink bottles. The high-performance polymer poly benzimidazole is produced from iso phthalic acid.
Verwenden
Purified Isophthalic Acid (PIA) is mainly used as intermediate for high performance UPR, resins for coatings, high solids paints, gel coats, modifier of PET for bottles. Product Data Sheet
Herstellung & Synthese
synthetische
Iso phthalic acid is produced on the billion kilogram per year scale by oxidizing meta-xylene using oxygen . The process employs a cobalt-manganese catalyst. In the laboratory, chromic acid can be used as the oxidant. It also arises by fusing potassium meta-sulpho benzoate , or meta - brom benzoate with potassium formate (terephthalic acid is also formed in the last case). The barium salt (as its hexa hydrate) is very soluble (a distinction between phthalic and terephthalic acids). Uvitic acid, 5- methylisophthalic acid, is obtained by oxidizing mesitylene or by condensing pyroracemic acid with baryta water.