Name | 2-Imidazolidinethione |
Synonyms | Ethenethiourea Ethlenethiourea Ethylene thiourea 2-imadazoline-2-thiol 2-mercaptoimidazoline 2-Imidazoline-2-thiol 2-Imidozolidimethione 2-Imidazolidinethione Rubber Accelerator ETU 1,3-Ethylene-2-thiourea 1,3-ethylene-2-thio-ure 2-Mercapto-2-imidazoline Rubber Accelerator NA-22 2H-Imidazole-2-thione, tetrahydro- 2-Imidazolidinethione ethylene thiourea |
CAS | 96-45-7 |
EINECS | 202-506-9 |
InChI | InChI=1/C3H6N2S/c6-5-2-1-4-3-5/h3,6H,1-2H2 |
InChIKey | PDQAZBWRQCGBEV-UHFFFAOYSA-N |
Molecular Formula | C3H6N2S |
Molar Mass | 102.16 |
Density | 1.41~1.45 |
Melting Point | 196-200°C(lit.) |
Boling Point | 240°C (1010 hPa) |
Flash Point | 252 °C |
Water Solubility | 19 g/L (20 ºC) |
Solubility | Soluble in hot water. At 90°C, 44 grams of this product can be dissolved in 100 ml of water, but only 2 grams can be dissolved in 30°C of water. Soluble in alcohol, ethylene glycol and pyridine, insoluble in ether, benzene, chloroform and petroleum ether. |
Vapor Presure | <1 hPa (25 °C) |
Appearance | White to Light Green Crystal |
Color | White |
Merck | 14,3803 |
BRN | 106275 |
pKa | 15.01±0.20(Predicted) |
Storage Condition | Store below +30°C. |
Sensitive | Easily absorbing moisture |
Refractive Index | 1.5500 (estimate) |
MDL | MFCD00005276 |
Physical and Chemical Properties | Melting point 197-201°C flash point 252°C water-soluble 19g/L (20°C) |
Use | Used as an accelerator for synthetic rubber |
Hazard Symbols | T - Toxic |
Risk Codes | R61 - May cause harm to the unborn child R22 - Harmful if swallowed R48/23/25 - R40 - Limited evidence of a carcinogenic effect |
Safety Description | S53 - Avoid exposure - obtain special instructions before use. S45 - In case of accident or if you feel unwell, seek medical advice immediately (show the label whenever possible.) |
UN IDs | 2811 |
WGK Germany | 2 |
RTECS | NI9625000 |
HS Code | 29332990 |
Hazard Class | 6.1(b) |
Packing Group | III |
Toxicity | LD50 orally in rats: 1832 mg/kg (Graham, Hansen) |
LogP | -0.67 at 20℃ |
NIST chemical information | information provided by: webbook.nist.gov (external link) |
(IARC) carcinogen classification | 3 (Vol. Sup 7, 79) 2001 |
EPA chemical substance information | information provided by: ofmpeb.epa.gov (external link) |
Introduction | ethylene thiourea is an imidazoline vulcanization accelerator, pure white needle-like crystals, slightly soluble in water, with a weak ammonia odor. Ethylene thiourea has been widely used in chloroprene rubber and other rubber curing, but also a small amount of used in the production of pesticides, but because of its harm to the human body, has been basically eliminated. |
toxicity | The LD50 of ethylene thiourea is 1832mg/kg (oral administration to rats), which belongs to low toxicity chemical substance. There is no uniform standard for the environmental concentration limit of ethylene thiourea. Some states in the United States have a limit of 0 to 0.7 μg/m3 in air, and EPA currently recommends a limit of 0.44 μg/L in water. |
hazard | ethylene thiourea belongs to the International Agency for Research on Cancer (IARC). The third category of carcinogens-carcinogenicity to humans is uncertain (once category 2B), but in animal experiments, carcinogenic and teratogenic tests are positive. In the carcinogenicity experiment in mice, ethylthiourea caused thyroid follicular carcinoma, anterior pituitary gland tumor and liver cancer; In rats, it caused thyroid epithelial cell carcinoma. In addition, like antithyroid substances such as thiourea and propylthiouracil, ethylene thiourea can cause goiter in humans. It has been reported that ethylene thiourea can also cause myxedema, fetal malformation. |
Use | used for chloroprene rubber, chlorosulfonated polyethylene rubber, chloroethanol rubber, accelerator of polyacrylate rubber This product is an imidazoline vulcanization accelerator, which can be used for chloroprene rubber, chlorohydrin rubber, chlorinated polyethylene, etc., and is especially suitable for being used as an accelerator for chlorobutylamine in non-vulcanized systems. Can often 100-500 deg C, select the appropriate system, can be carried out with the best rapid vulcanization, and operation safety. Its vulcanized products have high tensile strength and small permanent compression deformation, and the effect of non-vulcanized system for W-type (I. E. 54-1 type Chloroprene Rubber) is remarkable. It is usually used together with zinc oxide and magnesium oxide, mainly used for industrial products, coated wires, shoes and clothing and other neoprene products. Ethylene thiourea is an auxiliary brightener for copper sulfate. It is also used as an intermediate in fine chemistry for the manufacture of antioxidants, insecticides, fungicides, dyes, pharmaceuticals and synthetic resins. In 2000, there were three major ethylene thiourea producers in China, France, Japan, two in Germany, and one in Brazil, the Netherlands, India, Italy, and Switzerland. However, the use of ethylene thiourea is decreasing due to its harmfulness to the environment and its difficulty in decomposing in the soil. The ethylenethiourea used at present is mainly a polymer particle, in order to avoid the contact of workers to the skin of ethylenethiourea dust or inhalation. This product is soluble in hot alcohol solution. It is used as a copper plating brightener, often used in combination with acidic copper plating brightener M,SPS, etc. 2-imidazolidinethione is a pesticide used in the production of fruits and vegetables. It is also used as a novel contrast agent for MRI studies based on Proton Chemical Exchange-dependent saturation transfer (1). 2-imidazolidinethione is also a corrosion inhibitor (2) due to the adsorption of molar species. Candidate List of Drinking Water Contaminants 3 (CCL 3) compounds according to the U. S. Environmental Protection Agency (EPA), environmental and food contaminants. |
production method | in a glass-lined reaction pan, add water and ethylenediamine, cool to 20 ℃, add carbon disulfide, the reaction was controlled at 35 to 40 ° C. For 4 hours, and the temperature was raised to recover carbon disulfide to produce vinyl dithiocarbamate. The vinyl dithiocarbamate is cooled to below 50 ° C., hydrochloric acid is added, and hydrogen sulfide is released by warming up, and ethylene thiourea is generated by cyclization. In the cyclization reaction, acetic acid can also be used instead of hydrochloric acid to carry out the reaction, and the obtained crude ethylene thiourea is dissolved in boiling water, filtered, cooled to precipitate crystals, dehydrated, dried and pulverized to obtain a finished product. (kg/t) ethylenediamine (70%) 740 carbon disulfide (95%) 1250 24 kg ethylenediamine, 48 kg industrial alcohol and 60 kg distilled water were sequentially put into the reaction kettle. Under stirring, 32kg CS2 was slowly added, and the temperature was controlled at about 60 ° C. During the dropwise addition. After adding CS2, the temperature was raised to 100 ℃ and refluxed for 1 h. Then 3.6 concentrated hydrochloric acid was added and refluxed for 9-10 h. Cooling crystallization. The product was dried by Suction filtration and washing with acetone. The yield was about 80%-85%. |
toxic substance data | information provided by: pubchem.ncbi.nlm.nih.gov (external link) |