Methylamine is an organic compound with chemical formula CHthreeNHtwoIt is colorless gas under normal temperature and pressure, with a specific gravity of 1.07 times that of air. It is flammable and explosive, and has a strong irritating ammonia odor.
Listed in the List of Explosive Hazardous Chemicals[1]，It shall be controlled in accordance with the Public Security Management Measures for Explosive Hazardous Chemicals[2]。
Solubility: soluble in water, ethanol, ether, benzene, acetone, etc[4]
Molecular structure data
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Molar refractive index: 10.21
Molar volume (cmthree/mol）：48.7
Isotonic specific volume (90.2K): 100.9
Surface tension (dyne/cm): 18.4
Polarization (10-24cmthree）：4.05[4]
Calculate chemical data
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Reference value for drainage parameter calculation (XlogP): 0.7
Number of hydrogen bond donors: 1
Number of hydrogen bond receptors: 1
Number of rotatable chemical bonds: 0
Number of tautomers: 0
Topological molecular polar surface area: 26
Number of heavy atoms: 2
Surface charge: 0
Complexity: 2
Number of isotope atoms: 0
Determine the number of atomic structure centers: 0
Number of uncertain atomic structure centers: 0
Determine the number of chemical bond structure centers: 0
Number of uncertain chemical bond structure centers: 0
Number of covalent bond units: 1[4]
toxicology data
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1. Acute toxicity
LCfifty：2400mg/mthree(Inhalation in mice, 2h).
2. Irritation
Rabbit skin: 1.0 mL of 40% solution can cause rabbit skin irritation and necrosis.
Rabbit eyes: 4% solution can cause corneal injury.
3. Subacute and chronic toxicity
Guinea pigs inhaled 0.25 mg/L for 93 days, then 0.5 mg/L for 30 days. At the beginning, there was transient stimulation, and finally failure and hepatic prothrombin formation dysfunction occurred.
4. Mutagenicity:
Rats inhaled 10 μ g/mthreeThe dominant lethal test was positive, and 3mmol/L could induce lymphocyte mutation in mice.[3]
Ecological data
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1. Ecotoxicity
LCfifty: 10~30mg/L (96h) (fish)
ECfifty: 480mg/L (48h) (Daphnia)
2. Biodegradability
OECD screening test degraded 96%.
3. Non biodegradable
In the air, when the concentration of hydroxyl radical is 5.00 × 10fivePcs/cmthreeThe half-life of degradation is 18h (theoretical).[4]
purpose
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Monomethylamine has a wide range of industrial uses, mainly used as raw materials for medicine, pesticides (carbaryl, dimethoate, chlordimeform, etc.), dyes (alizarin intermediates, anthraquinone intermediates, etc.), explosives and fuels (water gel explosives, monomethylhydrazine, etc.), surfactants, accelerators, rubber aids, photographic chemicals, solvents, etc.
First aid measures
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Skin contact: Take off the contaminated clothes immediately, wash with a large amount of flowing water for at least 15min, and seek medical advice.
Eye contact: immediately lift the eyelids, thoroughly flush with a large amount of flowing water or physiological saline for at least 15min, and then seek medical advice.
Inhalation: quickly leave the site to a place with fresh air.Keep the respiratory tract unobstructed.If breathing is difficult, give oxygen.If breathing stops, perform artificial respiration immediately and seek medical advice.
Ingestion: Rinse mouth with water, drink milk or egg white, and seek medical advice.
Protective measures
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Respiratory system protection: when the concentration in the air exceeds the standard, it is recommended to wear a self-priming filter gas mask (full face mask).It is recommended to wear oxygen respirator or air respirator during emergency rescue or evacuation.
Eye protection: protection has been made in respiratory system protection.
Body protection: Wear anti-static work clothes.
Hand protection: wear rubber gloves.
Others: Smoking, eating and drinking are strictly prohibited at the work site.After work, take a shower and change clothes.
Operation, disposal, storage and transportation
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Operation management: close operation, strengthen ventilation.Operators must be specially trained and strictly abide by the operating procedures.It is recommended that operators wear self-priming filter type gas mask (full mask), anti-static work clothes and rubber gloves.Keep away from kindling and heat sources, and smoking is strictly prohibited in the workplace.Use explosion-proof ventilation systems and equipment.Prevent gas leakage into the air of the workplace.Avoid contact with oxidants, acids and halogens.During transmission, the cylinder and container must be grounded and bridged to prevent static electricity.The cylinder and accessories shall be handled with care to prevent damage.Fire fighting equipment and leakage emergency treatment equipment of corresponding types and quantities shall be provided.
Storage management: stored in a cool and ventilated warehouse.Keep away from kindling and heat sources.The warehouse temperature should not exceed 30 ℃.Keep container sealed.It should be stored separately from oxidants, acids, halogens, etc., and should not be mixed.Explosion proof lighting and ventilation facilities shall be adopted.It is prohibited to use mechanical equipment and tools that are easy to generate sparks.The storage area shall be equipped with leakage emergency treatment equipment.
Transportation management: The railway transportation time limit of this product is to use the self provided tank cars of pressure resistant liquefied gas enterprises for shipment, and it needs to be reported to the relevant departments for approval before shipment.The railway non tank transportation shall be carried out in strict accordance with the dangerous goods loading table in the Dangerous Goods Transportation Rules of the Ministry of Railways.The safety helmet on the cylinder must be worn when the cylinder is used for transportation.Cylinders are generally placed horizontally, and the mouth of the cylinder should be in the same direction, not crossed;The height shall not exceed the protective fence of the vehicle, and shall be firmly clamped with triangular wood pad to prevent rolling.The transport vehicles shall be equipped with corresponding types and quantities of fire-fighting equipment.The exhaust pipe of the vehicle transporting this article must be equipped with a fire retardant device. It is prohibited to use mechanical equipment and tools that are easy to generate sparks for loading and unloading.It is strictly prohibited to mix with oxidants, acids, halogens, edible chemicals, etc.Transport in the morning and evening in summer to prevent sunlight exposure.Keep away from kindling and heat sources during stopover.Road transportation shall be carried out according to the specified route, and it is forbidden to stay in residential areas and densely populated areas.It is forbidden to slip during railway transportation.
Emergency medical treatment
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Diagnostic points
1. Inhalation poisoning
(1) Have a clear history of inhalation of methylamine gas.Large area of skin burns can also be accompanied by monomethylamine absorption.
(2) Latency period: poisoning symptoms can appear within several minutes.
(3) Eye and upper respiratory tract irritation and burns: there may be tears, photophobia, eye pain, runny nose, choking cough, expectoration, sore throat, hoarseness, chest tightness, chest tightness, etc.The examination showed pharyngeal congestion, uvula edema, eyelid spasm, swelling, conjunctival congestion and edema, corneal epithelium damage or ulcer, etc.Inhalation of extremely high concentration can cause glottis spasm, laryngeal edema, and even suffocation.
(4) Respiratory system damage: choking and expectoration are the first symptoms, and chest tightness, shortness of breath, irritability and dyspnea may occur.In severe cases, laryngeal edema, pulmonary edema, even ARDS, etc.
(5) Pneumothorax, atelectasis, mediastinal emphysema, subcutaneous emphysema, sudden death, etc. can be complicated.
(6) Laboratory examination: ① Chest X-ray can show signs of acute bronchitis, peribronchitis, pneumonia, interstitial pulmonary edema, alveolar pulmonary edema, etc. ②Blood gas analysis showed hypoxemia.
2. Skin burns
Acute monomethylamine poisoning is often accompanied by skin burns, and the incidence is very high.Generally I °~II ° burns, and a few II ° burns.It was reported that a patient with 20% skin burn caused by monomethylamine had no serious symptoms at admission.The skin burn wound was not cleaned in time, and after 36 hours, the dyspnea became worse. Both lungs were full of moist rales, and hypoxemia occurred. The patient died after rescue.It is suggested that patients with large area of skin burns should be alert to the fact that monomethylamine can be absorbed through the skin and aggravate systemic poisoning.
Handling principles
(1) The patient should quickly move away from the site, change the contaminated clothes, and immediately flush the contaminated eyes and skin with a large amount of water for at least 10 minutes.
(2) Rest in bed, observe closely for 48 hours, and give corresponding treatment as early as possible if the condition changes.
(3) Keep the respiratory tract unobstructed.The bronchospasmolysis agent and defoamer (such as 10% dimethicone oil) can be inhaled through drug atomization.If necessary, tracheotomy shall be performed.Pay attention to body position drainage and encourage patients to cough up necrotic mucosa.
(4) Reasonable oxygen therapy.The concentration of inhaled oxygen should not be more than 60%. In case of acute carbon dioxide retention, while actively improving ventilation, adjust the oxygen supply concentration to make the blood oxygen saturation (SaOtwo）>90%；If high concentration oxygen needs to be inhaled, positive end expiratory pressure (PEEP) can be given. PEEP pressure should be<0.49 kPa (5cm HtwoO) Is appropriate.
(5) Adrenal glucocorticoid was given early, in sufficient quantity and short course.
(6) In the early stage of the disease, the amount of fluid replacement and infusion speed should be strictly limited, and attention should be paid to correcting acidosis, alkalosis and electrolyte disorders.
(7) Early application of antibiotics to prevent secondary infection.
(8) Actively prevent and treat complications.
(9) Strengthen the specialized nursing and treatment of eye and skin burns.
Monitoring methods
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1. On site emergency monitoring method: p-nitroaniline diazonium salt colorimetry.
2. Laboratory monitoring method: gas chromatography.
In the international standard classification, the detection method of monomethylamine involves the general method of food test and analysis, non-metallic minerals, food synthesis, sugar, sugar products, starch, medical equipment, biology, botany, zoology, laboratory medicine, footwear, organic chemistry, foam materials, air quality, plastics, building materials, chemical products, beverages, crime preventionTextile products, water quality, analytical chemistry, fuel, occupational safety, industrial hygiene, pesticides and other agrochemical products, articles and materials in contact with food, metrology and measurement integration, vocabulary, agriculture and forestry, milk and dairy products, feed, veterinary medicine, tobacco, tobacco products and tobacco industrial equipment, printing technology, medical science and health care device integrationTextile fiber, inorganic chemistry, nonferrous metals.
In the Chinese standard classification, the detection method of monomethylamine involves basic standards and general methods, food hygiene, other non-metallic minerals, melons and fruits, vegetable planting and products, sugar making, biochemical reagents, clinical analysis reagents, poultry, egg processing and products, crime identification technology, shoes, boots, labor hygiene, synthetic resin, plastic basic standards and general methods, meat processing productsSynthetic leather, synthetic leather, analytical method of toxic substances in the water environment, chemical reagent synthesis, animal husbandry synthesis, pesticides, signs, packaging, transportation, storage, standardization, quality management, animal quarantine, veterinary medicine and disease prevention, chemical synthesis, special equipment and equipment for coal mines, milk and dairy products, medicine, tobacco synthesis, printing technology, cosmeticsAnalytical methods for light metals and their alloys, analytical methods for rare metals and their alloys, analytical methods for powder metallurgy, and forensic medicine.
security information
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Safety terminology
S3/7：Keep container tightly closed in a cool place.
Keep the container tightly closed in a cool place.
S16：Keep away from sources of ignition - No smoking.
Keep away from ignition sources and no smoking.
S26：In case of contact with eyes, rinse immediately with plenty of water and seek medical advice.
After eye contact, immediately flush with plenty of water and seek medical advice.
S29：Do not empty into drains.
Do not discharge into the sewer.
S33：Take precautionary measures against static discharges.
Take precautions against static electricity.
S36/37/39：Wear suitable protective clothing, gloves and eye/face protection.
Wear appropriate protective clothing, gloves and eye/face protection.
S45：In case of accident or if you feel unwell, seek medical advice immediately (show the lable where possible).
In case of an accident or feeling unwell, seek medical advice immediately (show the label if possible).
