Polyether_Polyether Polyol Knowledge 4-Aminosalicylic Acid 4-Aminosalicylic Acid

4-Aminosalicylic Acid 4-Aminosalicylic Acid

4-aminosalicylic acid structural formula

Structural formula

Business number 01DV
Molecular formula C7H7NO3
Molecular weight 153.14
label

4-amino-2-hydroxybenzoic acid,

4-Amino-2-hydroxybenzoic acid,

PASF,

polyphenylsulfone,

Adhesive

Numbering system

CAS number:65-49-6

MDL number:MFCD00007789

EINECS number:200-613-5

RTECS number:VO1225000

BRN number:473071

PubChem number:24891299

Physical property data

1. Properties: White crystalline powder. Odorless or slightly sour smell. Sensitive to light. Easily turns brown when exposed to air.

2. Density (g/mL, 25/4℃): 1.371

3. Relative vapor density (g/mL, air=1): Undetermined

4. Melting point (ºC): 150~151 (decomposes and foams)

5. Boiling point (ºC, normal pressure): Undetermined

6. Boiling point (ºC ,5.2kPa): Not determined

7. Refractive index: 1.652

8. Flash point (ºC): Not determined

9. Specific rotation ( º): Not determined

10. Autoignition point or ignition temperature (ºC): Not determined

11. Vapor pressure (kPa, 25ºC): Not determined

12. Saturated vapor pressure (kPa, 60ºC): Undetermined

13. Heat of combustion (KJ/mol): Undetermined

14. Critical temperature (ºC): Undetermined Determined

15. Critical pressure (KPa): Undetermined

16. Log value of oil-water (octanol/water) partition coefficient: Undetermined

17 . Explosion upper limit (%, V/V): Undetermined

18. Explosion lower limit (%, V/V): Undetermined

19. Solubility: above 40℃ The aqueous solution is unstable, decomposes and releases carbon dioxide to become meta-aminophenol. 1g of product is dissolved in 21ml of ethanol and about 500ml of water. Soluble in dilute nitric acid, dilute sodium hydroxide solution, slightly soluble in ether, almost insoluble in benzene.

Toxicological data

Acute toxicity: Mouse oral LD50: 4 mg/kg; Mouse intraperitoneal LD50: 4250 mg/kg; Mouse subcutaneous injection LD50: 4 mg/kg; Mouse intravenous LD50: 3898 mg/kg; Rabbit oral LD50: 3650 mg/kg; mutagenicity: mouse oral Cytogenetic analysis: 50 mg/kg; skin/eye irritation: rabbit Administration into the eye Standard Draize test: 100 mg/24 HREACTION SEVERITY: Moderate

Ecological data

None yet

Molecular structure data

  1. Molar refractive index: 39.30

2. Molar volume (cm3/mol): 102.6

3. Isotonic specific volume (90.2K) :310.2

4. Surface tension (dyne/cm): 83.3

5. Polarizability (10-24cm3): 15.57

Compute chemical data

1. Hydrophobic parameter calculation reference value (XlogP): 1.3

2. Number of hydrogen bond donors: 3

3. Number of hydrogen bond acceptors: 4

4. Number of rotatable chemical bonds: 1

5. Number of tautomers: 12

6. Topological molecular polar surface area (TPSA): 83.6

p>

7. Number of heavy atoms: 11

8. Surface charge: 0

9. Complexity: 160

10. Number of isotope atoms : 0

11. Determine the number of atomic stereocenters: 0

12. Uncertain number of atomic stereocenters: 0

13. Determine the chemical bond configuration Number of centers: 0

14, Number of uncertain chemical bond stereocenters: 0

15, Number of covalent bond units: 1

Properties and stability

None yet

Storage method

This product should be sealed and stored away from light.

Synthesis method

1. Obtained from hydroxylation of m-aminophenol. Put water, m-aminophenol and sodium bicarbonate into the reaction tank in sequence, introduce carbon dioxide to replace the air, seal and raise the temperature to 110±1°C, keep the pressure in the tank at 0.6-0.8MPa, react for 6 hours, cool to -5°C, and add sodium sulfite , filter, wash with water, and combine the filtrate for acidification. The filter cake is meta-aminophenol recycling material, apply. Warm the above-mentioned filtrate to 10-15°C, neutralize it with 30-40% sulfuric acid until the pH is 6.4-7.0, add an appropriate amount of sodium sulfite and sodium sulfide solution, and after decolorizing the resin, adjust it with 30-40% sulfuric acid at 30°C. until the pH is 3-3.5, leave it alone, filter, wash with water until the sulfate radical is qualified, and spin dry to obtain p-aminosalicylic acid. Para-aminosalicylic acid can also be synthesized starting from phenylacetic acid. First, phenylacetic acid is nitrated in concentrated sulfuric acid and concentrated nitric acid at 60°C, then poured into ice water, and filtered to precipitate 2,4-dinitrophenylacetic acid [643-43-6]. The nitrification yield is 95%. Add the obtained product to 10 times of methanol, mix evenly, add dry hydrogen chloride, heat to boiling, cool and precipitate 2,4-dinitrophenylacetic acid methyl ester crystals [58605-12-2]. The esterification yield was 80%. Dissolve the esterified product in hot methanol, add butyl nitrite, and then add sodium methoxide, let stand for several hours until the dark red precipitate is completely precipitated, and separate the precipitate to obtain the intermediate product. Dissolve it in dilute potassium hydroxide solution and add hydrochloric acid to make it acidic. Carbon dioxide gas is released and 4-nitro-2-hydroxybenzonitrile is precipitated. The yield is 80%. Mix this nitrile with water, concentrated sulfuric acid, and glacial acetic acid and heat it to boiling to precipitate 4-nitrosalicylic acid [619-19-2]. Dissolve 4-nitrosalicylic acid in 25% sodium carbonate solution, add ferrous sulfate aqueous solution, add an appropriate amount of sodium carbonate solution, heat to boiling, and separate out the iron salt. Filter, and adjust the filtrate to pH=3 with acetic acid, and 4-aminosalicylic acid will precipitate. Then filter and dry to obtain the product. The content of para-aminosalicylic acid in industrial products is greater than 70%, chloride is less than 50ppm, and sulfate is less than 500ppm.

2.Preparation of structure Ⅰpolyarylsulfone: Add diphenyl ether disulfonyl chloride and biphenyl in an equal molar ratio to the reaction kettle. Benzene was used as the solvent and ferric chloride was used as the catalyst. The reaction was carried out at 130°C for about 20 hours until the intrinsic viscosity of the reactants reached above 0.66dL/g. Pour the material into methanol or acetone, mash it, and separate out the solid resin. After washing, drying, and granulating, the product is obtained. The polymerization reaction formula is as follows:

3.Structure II poly Aryl sulfone is prepared by polycondensation at 220°C using bisphenol sodium salt and 4,4′-bis(4-chlorophenylsulfonyl)biphenyl as raw materials, using sulfolane as solvent. The condensation polymerization reaction can adopt a two-step method, that is, first prepares bisphenol sodium salt and then condensation polymerization. A one-step method can also be used, that is, placing equal molar ratios of bisphenol S, 4,4′-bis(4-chlorophenylsulfonyl)biphenyl and a certain amount of sulfolane solvent and dehydrating agent xylene in a reaction kettle, and heating Melt, add NaOH (2 times the mole of bisphenol S) below 80°C, then raise the temperature to dehydrate, then evaporate the xylene, and raise the kettle temperature to 220°C for polycondensation reaction. When the material reaches the specified viscosity, add a certain amount of sulfolane to dilute it, cool down, stop the reaction, isolate the polymer, boil, filter and dry to obtain powdery polyarylsulfone.

Purpose

Organic synthesis. medicine.

Pharmaceutical intermediate, used for the synthesis of anti-tuberculosis drug paraaminosulfate sodium. It is also used to analyze acid-base fluorescent indicators of reagents.

Pharmaceutical intermediate, used to synthesize the anti-tuberculosis drug sodium p-aminosalicylate

As a galvanizing brightener, leveling agent and leveling agent, used in alkaline galvanizing

Polyarylsulfone adhesive is oil-resistant and creep-resistant, with an operating temperature of -54 to 204°C. It can be used for many mechanical parts and high and low temperature resistant electrical insulation parts in high-speed jet aircraft. Because its compression modulus changes less under high temperature conditions, when fillers such as polytetrafluoroethylene and graphite are added, it can be used as high temperature and high load bearing materials and wear-resistant structural parts. Polyarylsulfone film can replace polyimide as a high-temperature film capacitor, and can be used as a high-grade insulator with mica composite materials. In addition, it can also be used as a coating and for spinning to make high-temperature resistant fabrics.

Leveling agent and leveling agent for alkaline galvanizing

Polyarylsulfone adhesive is oil-resistant and creep-resistant, with an operating temperature of -54~204℃ . It can be used for many mechanical parts and high and low temperature resistant electrical insulation parts in high-speed jet aircraft. Because its compression modulus changes less under high temperature conditions, when fillers such as polytetrafluoroethylene and graphite are added, it can be used as high temperature and high load bearing materials and wear-resistant structural parts. Polyarylsulfone film can replace polyimide as a high-temperature film capacitor, and can be used as a high-grade insulator with mica composite materials. In addition, it can also be used as a coating and for spinning to make high-temperature resistant fabrics.

This article is from the Internet, does not represent the position of Toluene diisocyanate reproduced please specify the source.https://www.polyether-factory.com/archives/14377

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