Phthalic anhydride What is the difference between tetrahydrophthalic anhydride and hexahydrophthalic

Methyl hexahydrophthalic anhydride can be understood under Puyang Huicheng Electronic Materials Co., Ltd. ****. Puyang Huicheng Electronic Materials Co., Ltd. specializes in the production and operation of cyclohydrogen resin curing agents - anhydrides and derivatives, LED and OLED intermediates, norbornene series, organic phosphine series, pharmaceutical and pesticide intermediates and other products, product diversification, acceptable customization, product sales worldwide, is a high-tech listed company.

Protective measures for phthalic anhydride 1) Protective measures for the workplace When feeding, transporting and storing phthalic anhydride, workers must strictly abide by the production operation procedures to reduce the escape of phthalic anhydride. The feeding port of the reaction tank should be designed with negative pressure suction and automatic weighing and feeding of materials as far as possible to prevent the material from escaping during weighing and feeding. Closed operation, local ventilation and detoxification.

Safety showers and eyewash equipment are provided. Regularly check the concentration of phthalic anhydride in the air at the production site. 2) Personal protective measures: Wear dust masks, safety glasses, acid-alkali plastic overalls, and rubber acid-alkali resistant gloves.

And be careful not to smoke, eat and drink in the workplace, and wash your hands before eating. After work, shower and change clothes. Pay attention to the cleanliness and hygiene of workers.

3) Pre-job examination items of occupational health examination: internal medicine, chest X-ray, pulmonary ventilation function, blood routine (blood eosinophil count), non-specific bronchial provocation test. Check items during on-the-job:

Medical examination, chest x-ray, pulmonary ventilation, complete blood count (blood eosinophil count), nonspecific bronchial provocation. The physical examination cycle shall be carried out in accordance with the requirements of the health department. Occupational contraindications:

People with distinctly specific constitutions and patients with cardiopulmonary disease should not be exposed to the poison. The emergency treatment of phthalic anhydride isolates the leakage contaminated area and restricts access. Cut off the source of fire.

It is recommended that emergency response personnel wear dust masks (full face masks) and anti-acid and alkali work clothes. Do not come into direct contact with spills. Small leaks:

Avoid dust and collect in a dry, clean, covered container with a clean shovel. Massive spills: Collect** or transport to a waste disposal site for disposal.

Methyltetrahydrophthalic anhydride and methylhexahydrophthalic anhydride are two different organic compounds that have some differences in their structure and properties. Methyltetrahydrophthalic anhydride, also known as methylcyclohexanone, with the chemical formula C7H12O, is a colorless liquid with a special aroma. It is an important solvent and chemical intermediate, widely used in dyes, resins, rubber, spices, medicine and other fields.

The molecular structure of methyltetrahydrophthalic anhydride has a cyclic knotted band structure, which is composed of 6 carbon atoms and 1 oxygen atom, and the carbon atom is surrounded by a hydrogen atom. Methyl hexahydrophthalic anhydride, also known as methylcycloheptanone, with the chemical formula C8H14O, is a colorless to pale yellow liquid that also has a special aroma. It is mainly used in the synthesis of fragrances, resins and polymer materials.

The molecular structure of methyl hexahydrophthalic anhydride has a cyclic structure consisting of 6 carbon atoms and 1 oxygen atom, with a hydrogen atom around each of the carbon annihilation atoms, in addition to an additional carbon atom and three hydrogen atoms. Therefore, compared with methyltetrahydrophthalic anhydride, methyl hexahydrophthalic anhydride has a larger molecular weight and a more complex molecular structure. Therefore, there are some differences in the structure and properties of methyltetrahydrophthalic anhydride and methyl hexahydrophthalic anhydride, mainly due to the different number of carbons in their molecules.

Methyl tetrahydrophthalic anhydride, also known as methyltetrahydrophthalic anhydride, referred to as METHPA, has 2 isomers, namely 4-methyltetrahydrophthalic anhydride and 3-methyltetrahydrophthalic anhydride, with melting points of 65 and 63 respectively, and is rarely used as a curing agent alone. The actual commodity is a liquid mixture of isomerized multiple heteropolymers. Molecular weight.

Pale yellow beard transparent oily liquid, relative density. Freezing point "A 20. Boiling point 115 155 .

Viscosity (25) 40 80mpa·s. Refractive index. Anhydride content 40%.

Neutralizing equivalent 81 85. Flash point 137 150. Soluble in propylene ketone, ethanol, toluene, etc.

It has good stability in the air, and it is not easy to precipitate crystals. Low toxicity, LD502102mg kg.

The paddle is derived from epoxy resin curing agents, solvent-free paints, laminates, epoxy adhesives, etc. It is used as an epoxy resin curing agent, which has excellent properties such as long-term storage at room temperature, low freezing point, low volatility and low toxicity. It is widely used in motors, dry-type transformers, high-voltage switches, mutual attack or state sensors, line output transformer auspicious voltages, household appliance capacitors, power capacitors and resistors, integrated circuits impregnation, pouring and winding, etc.

Appearance: soluble in general organic solvents, slightly soluble in petroleum ether. Appearance: white flake solid.

Vapor density: (vs air).

Vapor pressure: < mm Hg (20 °C).

Water solubility : reacts

Sensitivity: moisture sensitivebrn: 82341

Melting point 99 1

Flash point (open cup):

Iodine value: 164 168

Soluble in benzene, acetone, etc., hygroscopic. Specific gravity. Acid is formed in contact with water, which is corrosive. Flammability. Low toxicity, LD504590mg kg.

Chinese name: tetrahydrophthalic anhydride.

Chinese aliases: cis-1,2,3,6-tetrahydrophthalic anhydride; cis-1,2,3,6-tetrahydroester; tetrahydrophthalic anhydride; cyclohexanedicarboxylanhydride; tetrahydroanhydride; 1,2,3,6-Tetrahydrophthalic anhydride (THPA); Tetrahydrophthalic anhydride.

Product Name:tetrahydrophthalic anhydride Synonyms:1,2,3,6-tetrahydrophthalic anhydride; 3a,4,7,7a-tetrahydro-2-benzofuran-1,3-dione; 4-cyclohexene-1,2-dicarboxylic anhydride; cis-1,2,3,6-tetrahydrophthalic anhydride; cis-4-cyclohexen-1,2-dimethanoic anhydride; cis-4-cyclohexene-1,2-dicarboxylic anhydride; cis-4-tetrahydrophthalic anhydride; cis-delta4-tetrahydrophthalic anhydride; cis-thpa; tetrahydrophthalic anhydride; thpa; 1,3-isobenzofurandion,3a,4,7,7a-tetrahydro-,cis-; 3-isobenzofurandione,3a,4,7,7a-tetrahydro-,cis-1; 4,7,7a-tetrahydro-3-isobenzofurandioncis-3a; cis-3a,4,7,7a-tetrahydro-1,3-isobenzofurandione

Number: B1001

cas no：935-79-5

Molecular Formula: C8H8O3 Molecular Weight:

Used as a curing agent for epoxy resin adhesive, the reference dosage is 55 65 copies, the curing conditions are 140 16h or 200 1 2h, and the heat deformation temperature and width of the cured object are 118. THPA is more difficult to mix with epoxy resin, inconvenient to operate, can be carried out in the presence of sulfuric acid, phosphorus pentoxide and free isomerism reaction to obtain liquid tetrahydrophthalic anhydride, it is a mixture of four isomers, curing E-51 epoxy resin heat deflection temperature 118.

1.Properties: colorless transparent liquid.

2.Melting point ( ) below 15.

3.Boiling point (c): 137

4.Relative density (25 C, 4 C):

5.Viscosity (:

6..Solubility: It can be organically soluble with benzene, toluene, acetone, carbon tetrachloride, chloroform, ethanol and ethyl acetate.

agent miscibility.

Use 1: It can be used as a modifier for alkyd resin, epoxy resin curing agent, unsaturated polyester resin, pesticide and pharmaceutical raw materials.

Use 2: As an intermediate of organic synthesis raw materials, tetrahydrophthalic anhydride is generally used to produce alkyd resins and unsaturated polyester resins, coatings, and is also used as a curing agent for epoxy resins, and is also used in pesticides, vulcanization regulators, plasticizers and surfactants. Tetrahydrophthalic anhydride is mainly used as a raw material for the production of unsaturated polyester resin, mainly to improve the air dryness of the resin, especially in the production of high-grade resin putty and air-dry coatings.