Thioglykolsäure

Bezeichnung:Thioglykolsäure

CAS-Nr68-11-1

Englisch Name:Thioglycolic acid

CBNumberCB6477604

SummenformelC2H4O2S

Molgewicht92.12

MOL-Datei68-11-1.mol

Synonyma

Mercaptoessigsure

Thioglykolsäure

Ethan-2-thiol-1-s?ure

Thioglykolsäure physikalisch-chemischer Eigenschaften

Schmelzpunkt	−16 °C(lit.)
Siedepunkt	96 °C5 mm Hg(lit.)
Dichte	1.326 g/mL at 20 °C(lit.)
Dampfdichte	3.2 (vs air)
Dampfdruck	0.4 mm Hg ( 25 °C)
Brechungsindex	n20/D 1.505(lit.)
Flammpunkt	126 °C
storage temp.	Store at +2°C to +8°C.
Löslichkeit	Chloroform (Sparingly), Methanol (Sparingly)
pka	3.68(at 25℃)
Aggregatzustand	Liquid
Farbe	clear clear, colorless
Geruch (Odor)	strong unpleasant odor
PH	1 (H2O, 20℃)
Wasserlöslichkeit	soluble
Sensitive	Air Sensitive
Merck	14,9336
BRN	506166
Henry's Law Constant	5.2×10² mol/(m³Pa) at 25℃, HSDB (2015)
Expositionsgrenzwerte	TLV-TWA 1 ppm (～3.8 mg/m³) (ACGIH).
Stabilität	Air Sensitive
Kosmetik-Inhaltsstoffe Funktionen	DEPILATORY REDUCING ANTIOXIDANT HAIR WAVING OR STRAIGHTENING
InChI	1S/C2H4O2S/c3-2(4)1-5/h5H,1H2,(H,3,4)
InChIKey	CWERGRDVMFNCDR-UHFFFAOYSA-N
SMILES	OC(=O)CS
LogP	0.090
CAS Datenbank	68-11-1(CAS DataBase Reference)
NIST chemische Informationen	Acetic acid, mercapto-(68-11-1)
EPA chemische Informationen	Thioglycolic acid (68-11-1)

Sicherheit

Kennzeichnung gefährlicher	T,T+
R-Sätze:	23/24/25-34-26-24/25
S-Sätze:	25-27-28-45-36/37-28C-23
RIDADR	UN 1940
OEB	B
OEL	TWA: 1 ppm (4 mg/m3) [skin]
WGK Germany	1
RTECS-Nr.	AI5950000
F	9-13-23
Selbstentzündungstemperatur	662 °F
TSCA	TSCA listed
HazardClass	8
PackingGroup	II
HS Code	29309070
Speicherklasse	6.1C - Combustible acute toxic Cat.3 toxic compounds or compounds which causing chronic effects
Hazard Classifications	Acute Tox. 3 Dermal Acute Tox. 3 Inhalation Acute Tox. 3 Oral Aquatic Chronic 3 Eye Dam. 1 Skin Corr. 1B Skin Sens. 1B
Giftige Stoffe Daten	68-11-1(Hazardous Substances Data)
Toxizität	LD50 orally in rats: 0.15 ml/kg (Deichmann, Mergard)

Gefahreninformationscode (GHS)

Thioglycolic acid Chemische Eigenschaften,Einsatz,Produktion Methoden

ERSCHEINUNGSBILD
VISKOSE FARBLOSE FLüSSIGKEIT MIT CHARAKTERISTISCHEM GERUCH.
CHEMISCHE GEFAHREN
Zersetzung beim Verbrennen unter Bildung giftiger Rauche mit Schwefeloxiden und Schwefelwasserstoff. Mittelstarke Säure. Reagiert mit starken Oxidationsmitteln, Alkalien und organischen Verbindungen. Greift Stahl, Edelstahl und Aluminium an.
ARBEITSPLATZGRENZWERTE
TLV: 1 ppm (als TWA); Hautresorption; (ACGIH 2005).
MAK nicht festgelegt (DFG 2005).
AUFNAHMEWEGE
Aufnahme in den Körper durch Inhalation, über die Haut und durch Verschlucken.
INHALATIONSGEFAHREN
Beim Verdampfen bei 20°C kann sehr schnell eine gesundheitsschädliche Kontamination der Luft eintreten.
WIRKUNGEN BEI KURZZEITEXPOSITION
WIRKUNGEN BEI KURZZEITEXPOSITION:
Die Substanz verätzt die Augen die Haut und die Atemwege. Inhalation des Dampfes kann zu Lungenödem führen (s.Anm.). Exposition oberhalb der Arbeitsplatzgrenzwerte kann zum Tod führen. Die Auswirkungen treten u.U. verzögert ein. ärztliche Beobachtung notwendig. (s. Anm.)
LECKAGE
Gefahrenbereich verlassen! Fachmann zu Rate ziehen! Belüftung. Ausgelaufene Flüssigkeit möglichst in abdichtbaren Behältern sammeln. Reste mit Sand oder inertem Absorptionsmittel aufnehmen und an einen sicheren Ort bringen. Chemikalienschutzanzug mit umgebungsluftunabhängigem Atemschutzgerät.
R-Sätze Betriebsanweisung:
R23/24/25:Giftig beim Einatmen, Verschlucken und Berührung mit der Haut.
R34:Verursacht Verätzungen.
R26:Sehr giftig beim Einatmen.
R24/25:Giftig bei Berührung mit der Haut und beim Verschlucken.
S-Sätze Betriebsanweisung:
S25:Berührung mit den Augen vermeiden.
S27:Beschmutzte, getränkte Kleidung sofort ausziehen.
S28:Bei Berührung mit der Haut sofort abwaschen mit viel . . . (vom Hersteller anzugeben).
S45:Bei Unfall oder Unwohlsein sofort Arzt zuziehen (wenn möglich, dieses Etikett vorzeigen).
S36/37:Bei der Arbeit geeignete Schutzhandschuhe und Schutzkleidung tragen.
S23:Gas/Rauch/Dampf/Aerosol nicht einatmen(geeignete Bezeichnung(en) vom Hersteller anzugeben).
Beschreibung
Thioglycolic acid(TGA) is the organic compound HSCH₂CO₂H . It contains both a thiol (mercaptan) and a carboxylic acid. It is a clear liquid with a strong unpleasant odor. It is readily oxidized by air to the corresponding disulfide [SCH₂CO₂H]₂.
TGA was developed in the 1940s for use as a chemical depilatory and is still used as such, especially in salt forms, including calcium thioglycolate and sodium thioglycolate. TGA is the precursor to ammonium thioglycolate that is used for permanents. TGA and its derivatives break the disulfide bonds in the cortex of hair. One reforms these broken bonds in giving hair a "perm." Alternatively and more commonly, the process leads to depilation as is done commonly in leather processing. It is also used as an acidity indicator, manufacturing of thioglycolates, and in bacteriology for preparation of thioglycolate media.
TGA is also used in the making of tin stabilizers often used in certain polyvinyl chloride products (such as vinyl siding).
Thioglycolic acid is used as nucleophile in thioglycolysis reactions used on condensed tannins to study their structure.
Chemische Eigenschaften
Thioglycolic acid is a colorless liquid with a strong unpleasant odor like rotten eggs. It is a sensitive reagent for iron, molybdenum, silver, tin. With ferric iron a blue color appears, and when an alkali hydroxide is added to a solution contg ferrous salts and thioglycolic acid, a yellow precipitate forms.
Verwenden
Thioglycolic Acid is an organic compound containing both a thiol and a carboxylic acid. Thioglycolic Acid is a precursor to ammonium thioglycolate, a chemical used for permanents. Thioglycolic Acid is used in organic synthesis as a nucleophile in thioglycolysis reactions and is used as a S transfer agent for sulfonyl chloride synthesis.
Verwenden
Mercaptoacetic acid is used as a reagent formetals analysis; in the manufacture of thioglycolates, pharmaceuticals, and permanentwave solutions; and as a vinyl stabilizer.
Application
Thioglycolic acid is an intermediate in the production of thiomethoprol (caputril), biotin, thiozinc acid, sodium dithiosuccinate and other pharmaceuticals, and is also an intermediate in the synthesis of cysteine, hormonal agent, and industrial disinfectant. And an important raw material for the synthesis of sulfuric acid. Thioglycolic acid is used as antioxidant and stabilizer in pharmaceuticals to enhance the stability of the main drug and prolong the validity period of pharmaceutical preparations. Ammonium and sodium salts of thioglycolic acid are mainly used as curling agents, calcium salts can be used as depilatory agents, polymerization initiators, accelerators and chain transfer agents, and can be used for hair removal before cosmetic surgery and animal experiments. Thioglycolic acid is used to make epoxy resin, catalyst of bisphenol A, and it can also be used as the basic raw material for synthesizing PVC transparent plastic and organic antimony and organic tin heat stabilizer.
Thioglycolic acid is a sensitive reagent for the determination of iron, molybdenum, aluminum, tin, etc., and is an inhibitor of copper sulfide and iron sulfide minerals in beneficiation. In the petrochemical industry and the railway sector, it is used for cleaning and derusting of equipment and rails. It can be used as a crystallization nucleating agent in polypropylene processing and molding, as a modifier for coatings and fibers, as a blanket quickening agent, as a stabilizer raw material for polyvinyl chloride and rubber, as a cold perm agent, and as a pharmaceutical intermediate. Thioglycolic acid is used as a color developer for the photometric determination of molybdenum, rhenium and iron, and as a compounding masking agent.
synthetische
Thioglycolic acid is prepared from Sodium sulfide plus Sodium monochloride acetate to yield Dithioglycollic acid. Electrolysis of the latter acid yields the title material.
Definition
ChEBI: Thioglycolic acid is a sulfur-containing carboxylic acid. It is a conjugate acid of a thioglycolate(1-).
Allgemeine Beschreibung
A colorless liquid with an unpleasant odor. Density 1.325 g / cm3. Used to make permanent wave solutions and depilatories. Corrosive to metals and tissue.
Air & Water Reaktionen
Readily oxidized by air. Water soluble.
Reaktivität anzeigen
Mercaptoacetic acid is readily oxidized by air . Reacts readily with other oxidizing agents as well in reactions that may generate toxic gases. Incompatible with diazo and azo compounds, halocarbons, isocyanates, aldehydes, alkali metals, nitrides, hydrides, and other strong reducing agents. Reactions with these materials may generate heat and toxic and flammable gases. May react with acids to liberate hydrogen sulfide. Neutralizes bases in exothermic reactions. Reacts with cyanides, sulfites, nitrites, thiosulfates to generate flammable and toxic gases and heat. Reacts with carbonates and bicarbonates.
Hazard
Toxic by ingestion and inhalation, strong irritant to tissue, eyes, and skin.
Health Hazard
TOXIC; inhalation, ingestion or skin contact with material may cause severe injury or death. Contact with molten substance may cause severe burns to skin and eyes. Avoid any skin contact. Effects of contact or inhalation may be delayed. Fire may produce irritating, corrosive and/or toxic gases. Runoff from fire control or dilution water may be corrosive and/or toxic and cause pollution.
Health Hazard
Mercaptoacetic acid is a highly toxic and ablistering compound. Even a 10% solutionwas lethal to most experimental animals by dermal absorption. The oral LD50 value ofundiluted acid is less than 50 mg/kg (Patty1963). The lethal dose in rabbits by skinabsorption is 300 mg/kg. The acute toxicsymptoms in test animals include weakness,respiratory distress, convulsions, irritation ofthe gastrointestinal tract, and liver damage.
Mercaptoacetic acid is a severe irritant.Contact with eyes can cause conjunctivalinflammation and corneal opacity. Skin contact can result in burns and necrosis.
Brandgefahr
Combustible material: may burn but does not ignite readily. When heated, vapors may form explosive mixtures with air: indoors, outdoors and sewers explosion hazards. Contact with metals may evolve flammable hydrogen gas. Containers may explode when heated. Runoff may pollute waterways. Substance may be transported in a molten form.
Sicherheitsprofil
Poison by ingestion, skin contact, intraperitoneal, and intravenous routes. Moderately toxic by subcutaneous route. A corrosive irritant to skin, eyes, and mucous membranes. When heated to decomposition it emits toxic fumes of SOx. See also MERCAPTANS and HYDROGEN SULFIDE.
mögliche Exposition
Thioglycolic acid is used to make thioglycolates; in sensitivity tests for iron; in formulations of permanent wave solutions and depilatories; in pharmaceutical manufacture; as a stabilizer in vinyl plastics.
Carcinogenicity
Thioglycolic acid was not mutagenic in a number of Salmonella typhimurium strains with or without metabolic activation.
Versand/Shipping
UN1940 Thyoglycolic acid, Hazard class: 8; Labels: 8-Corrosive material.
läuterung methode
Mix the acid with an equal volume of *benzene; the *benzene is then distilled off to dehydrate the acid. After heating to 100o to remove most of the *benzene, the residue is distilled under vacuum and stored in sealed ampoules at 3o. [Eshelman et al. Anal Chem 22 844 1960, Beilstein 3 IV 1130.]
Inkompatibilitäten
Compounds of the carboxyl group react with all bases, both inorganic and organic (i.e., amines) releasing substantial heat, water and a salt that may be harmful. Incompatible with arsenic compounds (releases hydrogen cyanide gas), diazo compounds, dithiocarbamates, isocyanates, mercaptans, nitrides, and sulfides (releasing heat, toxic and possibly flammable gases), thiosulfates and dithionites (releasing hydrogen sulfate and oxides of sulfur). Air, strong oxidizers; bases, active metals, for example, sodium potassium, magnesium, and calcium. Readily oxidized by air. Thermal decomposition causes release of hydrogen sulfide. May attack various metals.
Waste disposal
Dissolve in flammable solvent and burn in furnace equipped with afterburner and alkaline scrubber.

Thioglycolic acid Upstream-Materialien And Downstream Produkte

Thioglykolsäure Anbieter Lieferant Produzent Hersteller Vertrieb Händler.

68-11-1, Thioglycolic acid Verwandte Suche:

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