What is the difference between styrene and ethylbenzene

1. molecular structure and composition

1.1 structure characteristics The molecular structure of styrene (C≡H) consists of a benzene ring and a vinyl group (CH₂ = CH₂), and the overall structure is C≡H-CH₂-CH₂. The molecular structure of ethylbenzene (C, HSC) is a single ring structure, consisting of 8 carbon atoms and 10 hydrogen atoms. The specific structure is C, H, in which two methyl groups are connected to the benzene ring.

1.2 molecular formula difference Styrene has the formula C≡H₂, while ethylbenzene has the formula C≡H₂. It can be seen that the two are different in the carbon-to-hydrogen ratio. The carbon-to-hydrogen ratio of styrene is 4:1, while the carbon-to-hydrogen ratio of ethylbenzene is 4:1.25. This difference leads to the different behavior of the two in physical properties and chemical reactions.

2. preparation methods and production background

2.1 preparation method The preparation of styrene is usually achieved by the hydrogenation reaction of ethylene on the benzene ring, the process is more complex, and strict control conditions are required to avoid side reactions. The preparation of ethylbenzene is relatively simple and can be obtained by dehydrogenation of ethylene and liquefied petroleum gas under the action of a catalyst.

2.2 production use Styrene is mainly used in the manufacture of polyester polymer materials, such as HDPE, LDPE, etc., and is widely used in the production of plastics, rubber and fiber materials. Ethylbenzene is mainly used in organic synthesis, such as the synthesis of benzoic acid, hydroquinone and other intermediates, while in the chemical industry is also used as a solvent and extractant.

3. physical and chemical properties

3.1 physical properties Styrene has a density of 0.94g/cm³, a melting point of -63°C and a boiling point of 209°C. Ethylbenzene has a density of 0.876g/cm³, a melting point of 5.7°C and a boiling point of 106.1°C. From these physical properties, it can be seen that styrene is more volatile at high temperatures, while ethylbenzene exhibits greater stability.

3.2 chemical properties Styrene has strong oxidation in the chemical reaction, and it is easy to react with strong oxidants such as KMnO4 to generate benzopyrene and other products. Ethylbenzene, on the other hand, is prone to dehydrogenation under acidic conditions, generating intermediates such as phenol.

4. application field

4.1 industrial applications Because of its excellent processing performance, styrene is widely used in plastics, rubber, textile fiber and other industrial fields. It not only has excellent mechanical properties, but also has good processing fluidity.

Use of 4.2 ethylbenzene As an important raw material for organic synthesis, ethylbenzene is widely used in the production of pharmaceuticals, dyes, spices and other fields. Ethylbenzene is also used as a solvent and extractant in the chemical industry and has important economic value.

5. summary

Both styrene and ethylbenzene are aromatic compounds, but there are significant differences in structure, molecular formula, physical properties and application fields. Understanding the difference between these two compounds will help us to better choose the right raw materials and processes to meet different industrial needs.

Through the detailed analysis of this article, we hope that readers can clearly understand the chemical nature of styrene and ethylbenzene and their important role in industrial production, and provide reference value for the study and research in the field of chemical engineering.