The difference between glacial acetic acid and vinyl acetate

In the field of chemistry, glacial acetic acid and vinyl acetate are similar in name, but there are significant differences in properties, structures and applications. This article will analyze the differences between these two substances in detail from multiple angles to help readers understand their characteristics and their practical applications more clearly.

Basic definition and structure of 1.

1. Definition of glacial acetic acid Glacial acetic acid (Acetic Acid) is a dibasic acid with a chemical formula of CH3COOH and a molecular weight of 60. It is an ice crystal form of acetic acid, colorless transparent liquid, acidic, pH value of about 2, liquid at room temperature. Glacial acetic acid is easily soluble in water at room temperature, and can also be miscible with ethanol, ether and other solvents, with a wide range of stability.

2. Definition of vinyl acetate Vinyl acetate (Acetic Elastomer) is a synthetic polyester with a chemical formula of CH3CO-O-CH2-CH2-..., which is polymerized by ethylene and acetic anhydride under the action of a catalyst. It is a colorless and transparent plastic with good elasticity. It is widely used in industrial manufacturing and daily life, such as plastic stabilizers, rubber plasticizers, etc.

Comparison of Chemical and Physical Properties of 2.

1. Chemical properties Glacial acetic acid is a strong acidic organic acid, with strong acidity, easy to react with alkaline substances. It dissociates into acetate ions and hydrogen ions in aqueous solution, which is highly corrosive. Glacial acetic acid is not polymerizable and cannot generate other substances by polymerization.

2. Chemical Properties of Ethylene Acid Vinyl acetate is a polymeric material formed by copolymerization of repeating vinyl acetate monomers. It has excellent thermal stability and chemical stability, and can exist stably under high temperature and high pressure. Vinyl acetate also has weak acidity, which is mainly reflected in the stability and plasticizing effect of certain organic compounds.

3. Physical characteristics Glacial acetic acid exhibits liquid properties in physical properties, with high solubility and low boiling point. It is liquid at room temperature, soluble in a variety of solvents.

Vinyl acetate is a polymer material with good shaping properties and processing properties. It is a solid at room temperature, but it can be converted into a liquid under certain conditions (such as high temperature and high pressure). The melting point of vinyl acetate is higher, about 100 ℃, compared with the melting point of glacial acetic acid, which is lower, about 17 ℃.

3. preparation method and production process

1. Preparation of glacial acetic acid The main preparation method of glacial acetic acid is by fermentation or strain method. Common fermentation methods include glucose fermentation and fruit vinegar fermentation. Glucose fermentation is commonly used in industry, using microorganisms to convert glucose into acetic acid. It can also be prepared by a chemical method, using ethanol and acetic acid to react with a catalyst to produce glacial acetic acid.

2. Preparation of Vinyl Acetate The preparation process of vinyl acetate mainly depends on the copolymerization reaction. Ethylene and acetic anhydride are copolymerized in the presence of a catalyst to produce a polymer with repeating vinyl acetate monomers. This process is usually carried out in industrial laboratories or chemical plants, requiring strict control of reaction conditions such as temperature, pressure and catalyst ratio.

4. main application areas

1. Application of glacial acetic acid Glacial acetic acid has a wide range of applications in daily life, such as food preservation, medicine, cosmetics and other fields. As an acidic substance, it can effectively inhibit the growth of bacteria and fungi and extend the shelf life of food and medicine. Ice carbon acetic acid is also used in the modulation of food additives to improve taste and color.

2. Application of Vinyl Acetate The application field of vinyl acetate is more extensive, it is widely used in the plastics industry, as a plastic stabilizer and plasticizer. Vinyl acetate plays an important role in automobile manufacturing, electronics industry, daily plastic industry and other fields. Vinyl acetate is also used as a rubber plasticizer and food additive to improve product performance and stability.

5. identification method

1. physical identification Glacial acetic acid and vinyl acetate can be initially distinguished by observing the morphology and state of the substance. Glacial acetic acid is liquid at room temperature, while vinyl acetate is solid at room temperature. When necessary, the difference in the melting point of the substance can also be observed by heating.

2. chemical identification Glacial acetic acid and vinyl acetate can be distinguished by acid-base test or pH paper test. Glacial acetic acid has obvious acidity, pH less than 3, while vinyl acetate is relatively neutral, pH between 4-6. Can also be more accurate identification by acidification test and other methods.

6. Summary

although glacial acetic acid and vinyl acetate are similar in name, they are significantly different in chemical properties, physical properties and application fields. Glacial acetic acid is a kind of organic acid with strong acidity and liquid characteristics, which is widely used in food, medicine and other fields. Vinyl acetate is a high molecular polymer with good thermal stability and chemical stability, and is mainly used in the plastic industry and rubber plasticization and other fields. Understanding the difference between these two substances has important reference value for scientific experiments, industrial production and daily life.