Name | Mercaptoacetic acid |
Synonyms | sulfanylacetate Thioglycolic acid 2-mercaptoacetate 2-thioglycolicacid Thioglycollic acid 2-thio-glycolicaci Thioglypollic Acid Mercaptoacetic acid 2-Thioglycolic acid acidethioglycolique Acide thioglycolique Aceticacid,mercapto- 2-MERCAPTOACETIC ACID Thioglycolic acid solution thioglycolic acid free acid |
CAS | 68-11-1 |
EINECS | 200-677-4 |
InChI | InChI=1/C2H4O2S/c3-2(4)1-5/h5H,1H2,(H,3,4)/p-1 |
InChIKey | CWERGRDVMFNCDR-UHFFFAOYSA-N |
Molecular Formula | C2H4O2S |
Molar Mass | 92.12 |
Density | 1.326g/mLat 20°C(lit.) |
Melting Point | −16°C(lit.) |
Boling Point | 96°C5mm Hg(lit.) |
Flash Point | 126 °C |
Water Solubility | soluble |
Vapor Presure | 0.4 mm Hg ( 25 °C) |
Vapor Density | 3.2 (vs air) |
Appearance | Liquid |
Color | clear clear, colorless |
Exposure Limit | TLV-TWA 1 ppm (~3.8 mg/m3) (ACGIH). |
Merck | 14,9336 |
BRN | 506166 |
pKa | 3.68(at 25℃) |
PH | 1 (H2O, 20℃) |
Storage Condition | Store at +2°C to +8°C. |
Sensitive | Air Sensitive |
Refractive Index | n20/D 1.505(lit.) |
Physical and Chemical Properties | The pure product is a colorless transparent liquid, and the industrial product is colorless to yellowish. melting point -16.5 ℃ boiling point 123 ℃ relative density 1.3253 refractive index 1.5030 BR> solubility and water, ethanol and ether are miscible. |
Use | Mainly used as raw materials of blanket finishing agent and cold scalding liquid; Used in the manufacture of liquid medicine; Used as a reagent and stabilizer for the determination of Iron |
Risk Codes | R23/24/25 - Toxic by inhalation, in contact with skin and if swallowed. R34 - Causes burns R26 - Very Toxic by inhalation R24/25 - |
Safety Description | S25 - Avoid contact with eyes. S27 - Take off immediately all contaminated clothing. S28 - After contact with skin, wash immediately with plenty of soap-suds. S45 - In case of accident or if you feel unwell, seek medical advice immediately (show the label whenever possible.) S36/37 - Wear suitable protective clothing and gloves. S28C - S23 - Do not breathe vapour. |
UN IDs | UN 1940 8/PG 2 |
WGK Germany | 1 |
RTECS | AI5950000 |
FLUKA BRAND F CODES | 9-13-23 |
TSCA | Yes |
HS Code | 29309070 |
Hazard Class | 8 |
Packing Group | II |
Toxicity | LD50 orally in rats: 0.15 ml/kg (Deichmann, Mergard) |
Raw Materials | Sodium sulfide Sulfuric acid Chloroacetic acid |
pure colorless transparent liquid, industrial products are colorless to yellowish. Melting Point -16.5 °c. Boiling point 123 ℃(3. 866kPa). The relative density was 1. 3253. Refractive index 5030. Miscible with water, ethanol and ether.
for the production of thioglycolate and salt products. Its esters can be used as a stabilizer for halogenated polyolefin, alkali metal salts can be used as fur depilatory agents, ammonium salts can be prepared for cold scalding, and other salts (such as iron salts, etc.) also have many uses. Thioglycolic acid can also be used as a sensitive solvent for iron, molybdenum, aluminum, tin, and the like.
use | Used as a chemical reagent |
use | TGA has both the reaction characteristics of hydroxy acid and the reaction characteristics of sulfhydryl groups. The most important reaction is the reaction with disulfide. Especially under alkaline conditions, it reacts with cystine in the hair to cut off the (-S-S-) bond of cystine to generate cysteine that is easy to curl. Mainly used as a rolling agent, depilating agent, polyvinyl chloride low-toxic or non-toxic stabilizer, polymerization initiator, accelerator and chain transfer agent, metal surface treatment agent. In addition, thioglycolic acid is a sensitive reagent for the determination of iron, molybdenum, aluminum, tin, etc.; it can also be used as a crystallization nucleating agent for polypropylene processing and molding, as well as a modifier for coatings and fibers, and a blanket agent. |
category | corroded articles |
toxicity classification | highly toxic |
acute toxicity | oral-rat LD50: 114 mg/kg; Oral-mouse LD50: 242 mg/kg |
Stimulus data | skin -3% |
flammability hazard characteristics | Combustible; combustion produces toxic sulfur oxide smoke |
storage and transportation characteristics | The warehouse is ventilated and dry at low temperature; it is stored separately from oxidants and alkalis. |
fire extinguishing agent | sand, foam, mist water |
occupational standards | TLV-TWA 1 PPM (4 mg/m3); STEL 3 PPM (15 mg/m3) |
It is obtained by the reaction of organic or inorganic sulfur compounds with sodium and potassium salts of monochloroacetic acid. For example, monochloroacetic acid reacts with sodium sulfide and sulfur to form dithiodiacetic acid, which is then reduced with zinc and acid; or thiocarbamate reacts with monochloroacetic acid, and its product is obtained by hydrolysis; monochloroacetic acid reacts with thiourea to generate isothiourea acetic acid, then barium hydroxide is used to convert the precipitation, and then sulfuric acid is acidified to make a thioglycolic acid.
melting point | −16 °C(lit.) |
boiling point | 96 °C5mm Hg(lit.) |
density | 1.326 g/mL at 20 °C(lit.) |
vapor density | 3.2 (vs air) |
Vapor pressure | 0.4mm Hg ( 25 °C) |
refractive index | n20/D 1.505(lit.) |
flash point | 126 °C |
storage conditions | Store at 2°C to 8°C. |
acidity coefficient (pKa) | 3.68(at 25℃) |
morphology | Liquid |
color | clear clear, colorless |
PH value | 1 (H2O, 20℃) |
water solubility | soluble |
sensitivity | Air Sensitive |
Merck | 14,9336 |
BRN | 506166 |
exposure limit | TLV-TWA 1 ppm (~3.8 mg/m3) (ACGIH). |
InChIKey | CWERGRDVMFNCDR-UHFFFAOYSA-N |
NIST chemical information | information provided by: webbook.nist.gov (external link) |
EPA chemical substance information | information provided by: ofmpeb.epa.gov (external link) |
Application | thioglycolic acid (TGA) is mainly used as a raw material for blanket finishing agent and cold-stamping liquid. TGA has the reaction characteristics of hydroxy acid, the reaction is characterized by a thiol group, the most important of which is the reaction with the disulfide. In particular, under alkaline conditions, it reacts with cystine in the hair to cut off the (-S-S-) bond of cystine to generate cysteine which is easy to curl. It is mainly used as hair rolling agent, hair removal agent, polyvinyl chloride low toxicity or non-toxic stabilizer, polymerization initiator, accelerator and chain transfer agent, metal surface treatment agent. In addition, thioglycolic acid is a sensitive reagent for the determination of iron, molybdenum, aluminum, tin and the like; It can also be used as a crystal nucleating agent in the processing and molding of polypropylene, as well as a modifier for coatings and fibers, and as a blanket agent. It is an intermediate for the production of drugs such as methyl thiopropyl (captoli), biotin, thizinc acid, and sodium dithiosuccinate. It is also a synthetic cysteine, hormonal agent, industrial disinfectants and important raw materials for the synthesis of sulfuric acid. In addition to being used as an intermediate of Cefivitril, thioglycolic acid is also widely used as a hair rolling agent, depilatory agent, PVC low toxicity or non-toxic stabilizer, metal surface treatment agent and polymerization initiator, accelerators and chain transfer agents. sensitive reagents of iron, molybdenum, silver and tin. Its ammonium salt and sodium salt are used as hair-cutting agent, calcium salt is hair-removing agent |
production method | is obtained by reacting organic or inorganic sulfur-containing compounds with sodium and potassium salts of monochloroacetic acid. For example, monochloroacetic acid reacts with sodium sulfide and sulfur to form dithiodiacetic acid, which is then reduced with zinc and an acid; Or thiocarbamate reacts with monochloroacetic acid, and its product is obtained by hydrolysis; Monochloroacetic acid reacts with thiourea, isothiourea acetic acid is formed, and then the conversion is precipitated with barium hydroxide, and then sulfuric acid is acidified to prepare the mercaptoacetic acid aqueous solution, and the 60%-70% solution is obtained by evaporation, and the yield is more than 70%. |
category | corrosive article |
toxicity grade | high toxicity |
Acute toxicity | oral-rat LD50: 114 mg/kg; Oral-mouse LD50: 242 mg/kg |
stimulation data | Skin-person 3% |
flammability hazard characteristics | flammability; Toxic sulfur oxide fumes from combustion |
storage and transportation characteristics | The warehouse is ventilated and dried at low temperature; It is stored separately from oxidants and alkalis. |
fire extinguishing agent | Sand, foam, water mist |
Occupational Standard | TLV-TWA 1 PPM (4 mg/m3); Tel 3 PPM (15 mg/m3) |
spontaneous combustion temperature | 662 ° F. |
toxic substance data | information provided by: pubchem.ncbi.nlm.nih.gov (external link) |