Styrene Styrene

Structural formula

• Numbering system
• Physical property data
• Toxicological data
• Ecological data
• Molecular structure data
• Computing chemical data
• More
  • Properties and Stability
  • Storage method
  • Synthesis method
  • Purpose

Numbering system

CAS number:100-42-5

MDL number:MFCD00008612

EINECS number:202-851-5

RTECS number:WL3675000

BRN number:1071236

PubChem number:24899624

Physical property data

1. Properties: colorless and transparent oily liquid ^[1]

2. Melting point (℃): -30.6^[2]

3. Boiling point (℃): 146^[3]

4. Relative density (water=1): 0.99 (25℃)^{[4 ]}

5. Relative vapor density (air=1): 3.6^[5]

6. Saturated vapor pressure (kPa): 0.7 (20℃)^[6]

7. Heat of combustion (kJ/mol): -4376.9^[7]

8. Critical temperature (℃): 369^[8]

9. Critical pressure (MPa): 3.81^[9]

10. Octanol/water partition coefficient: 3.2^[10]

11. Flash point (℃): 31^[11]

12. Ignition temperature (℃): 490^[12]

13. Explosion limit (%): 6.8^[13] sup>

14. Lower explosion limit (%): 0.9^[14]

15. Solubility: insoluble in water, soluble in ethanol, ether, etc. Most organic solvents. ^[15]

16. Viscosity (mPa·s, 25ºC): 0.696

17. Heat of evaporation (KJ/mol, 25ºC): 43.96

18. Heat of fusion (KJ/mol): 10.95

19. Heat of formation (KJ/mol, 25ºC, gas): 147.46

20. Heat of formation (KJ/mol, 25ºC, liquid): 103.96

21. Heat of combustion (KJ/mol, 25ºC, gas, constant pressure): 4441.78 (H2O liquid, CO2 gas)

22. Heat of combustion (KJ/mol, 25ºC, gas, constant pressure): 4265.64 (H2O gas, CO2 gas)

23. Heat of combustion (KJ/mol, 25ºC, liquid, pressure): 4398.28 ( H2O liquid, CO2 gas)

24. Heat of combustion (KJ/mol, 25ºC, liquid, pressure): 4222.14 (H2O gas, CO2 gas)

25. Specific heat capacity (KJ/ (kg·K), 25.16ºC, constant pressure): 1.17

26. Solubility (%, 25ºC, water): 0.031

27. Volume expansion coefficient (K ^-1): 0.00097

28. Relative density (20℃, 4℃): 0.90600

29. Refractive index at room temperature (n²⁵): 1.5420

30. Solubility parameter (J·cm^-3)^0.5: 19.127

31.van van der Waals area (cm²·mol^-1): 8.270×10⁹

32. van der Waals volume (cm³·mol^-1): 66.250

33. Gas phase standard combustion heat (enthalpy) (kJ·mol^-1): -4439.3

34. Gas phase standard claims heat (enthalpy) (kJ·mol^-1): 147.9

35. Gas phase standard Entropy (J·mol^-1·K^-1): 345.10

36.�1) The ethylbenzene oxidation reaction temperature is 100-150℃, the pressure is 0.3-0.5MPa, the reaction time is 3-5h, using ethylbenzene hydroperoxide as the initiator, anhydrous sodium carbonate as the auxiliary, and using air (110-160h- 1) Liquid phase oxidation to obtain ethylbenzene hydroperoxide.
2) The reaction of epoxidized propylene and ethylbenzene hydroperoxide, the ratio is (5-10): 1 (mol), the catalyst amount of molybdenum is 0.002 mol, the reaction temperature is 90-110°C, the reaction time 40-60min, the recovery pressure is 1.96-3.92MPa. After the reaction is completed, α-phenylethyl alcohol and ethylene oxide can be obtained.
3) Phenylethyl alcohol dehydration The reaction is carried out in a fixed bed, gas phase, and normal pressure. This reaction is an endothermic reaction, the dehydration temperature is 250-260°C, water vapor is used as the diluent, the water to alcohol ratio is 5 mol, the space velocity (liquid alcohol) is 5 h-1, and the catalyst is titanium dioxide. Under these conditions, the conversion rate of α-phenylethyl alcohol reaches 87%-92%, the single-pass yield of styrene is 85%, and the selectivity can reach more than 95%. In addition to obtaining styrene, this method can also co-produce ethylene oxide.

3. Acetophenone method: oxidize ethylbenzene to produce acetophenone, then hydrogenate acetophenone to produce α-phenylethanol, and dehydrate α-phenylethyl alcohol to produce styrene (the third method is the same as the above method). same steps). The yield of this method is lower than that of the ethylbenzene catalyst dehydrogenation method, only 78%-80%, and the reaction steps are high and the cost is high.

4. Preparation method:

Into a reaction bottle equipped with a stirrer, reflux condenser and thermometer, add 70g of quinoline and 0.5g of phenol^①, and heat with an electric heating mantle to 190°C. In addition, 70 g (0.5 mol) of a-chloroethylbenzene (2) was heated to 150°C, quickly added to the above reaction bottle, and the mixture was heated for 15 minutes, during which time the temperature of the mixture was reduced to 170~150°C. After cooling, pour it into 100mL of 10% dilute hydrochloric acid and stir thoroughly. Separate the upper organic layer ^②, wash with water twice, and dry over anhydrous calcium chloride. Fractionate under reduced pressure and collect the fractions at 40~50℃/2.67~3.3KPa to obtain 45g of styrene (1) with a yield of 87%. Note: ① The purpose of adding phenol is to prevent the polymerization of styrene, and phenol is a polymerization inhibitor. ② The crude product contains a small amount of unreacted a-chloroethylbenzene, which can be removed during fractionation (50~80℃/2.67~3.3KPa). ^[32]

5. Preparation method:

Into a 500mL reaction bottle equipped with a fractionation device, add 148g (1.0mol) of powdered cinnamic acid (2), 2g of hydroquinone, and a few grains of zeolite . Add 0.5g hydroquinone to the receiving bottle. Use an electric heating mantle to heat the reaction flask until styrene begins to elute. Adjust the heat source to keep the temperature at the top of the fractionation column at about 120°C and not exceed 130°C. Stop the reaction when no more styrene is distilled out, which takes about 4 to 5 hours. Add 100 mL of water to the distillate, heat and distill, and distill the styrene and water together until no oil is distilled. Separate the oil, dry it over anhydrous calcium chloride, and distill under reduced pressure. Collect the fraction at 44-46°C/5.3kPa to obtain 40g of styrene (1), with a yield of 38%. ^[33]

6. Preparation method

In a reaction flask equipped with a thermometer and an air condenser, add 59g (0.4mol) cinnamic acid (2), 129g quinoline, 6g anhydrous copper sulfate, and hydrogen Quinone 0.15g, heated by electric heating mantle. When it rises to 250°C, the reactant becomes very black and bubbles are produced. When the temperature rises to 280-290°C, the decomposition speed accelerates, and the mixture of styrene and quinoline is evaporated at the same time. The boiling point gradually rises from 150°C to 200°C, and reaches 220-230°C at the end of the reaction. Acidify the distilled solution with excess hydrochloric acid, separate the organic layer ^①, and wash with water, sodium carbonate solution, and water in sequence. Add 0.1g of hydroquinone, dry over anhydrous calcium chloride, and distill under reduced pressure. Collect the fraction at 71-72°C/9.31kPa to obtain 35g of styrene (1), with a yield of 84%. Note: ① The water layer contains quinoline hydrochloride. After steam distillation, 90% of the quinoline can be recovered. ^[34]
　

Purpose

1. The most important use is as a monomer for synthetic rubber and plastics, used to produce styrene-butadiene rubber, polystyrene, and foamed polystyrene; it is also used to copolymerize with other monomers to manufacture a variety of projects for different purposes. plastic. For example, ABS resin is made by copolymerizing with acrylonitrile and butadiene, which is widely used in various household appliances and industries; SAN made by copolymerizing with acrylonitrile is an impact-resistant, bright-colored resin; made by copolymerizing with butadiene SBS is a thermoplastic rubber that is widely used as a modifier for polyvinyl chloride, polypropylene, etc. In addition, a small amount of styrene is also used as intermediates such as spices. Styrene is chloromethylated to obtain cinnamonyl chloride, which is used as an intermediate for the non-narcotic analgesic Diantadine. Styrene is also used as the original drug of the antitussive and expectorant ethazine and the anticholinergic drug Wenchangine. It can also be used as a hard monomer for manufacturing styrene-acrylic emulsions and solvent-based pressure-sensitive adhesives, and as a cross-linking monomer for unsaturated polyester resins.

2. Used in organic synthesis and resin synthesis, and used to prepare copper plating brighteners for leveling and brightening.

3. It is used as a hard monomer for manufacturing styrene-acrylic emulsion and solvent-based pressure-sensitive adhesive, and can also be used as a cross-linking monomer for unsaturated polyester resin. Used to manufacture polystyrene, foamed polystyrene, styrene-butadiene rubber; copolymerized with acrylonitrile and butadiene to produce ABS resin; copolymerized with butadiene and isoprene to produce SBS and SIS thermoplastic elastomers respectively; and acetic acid Vinyl ester and acrylate copolymers are used to produce emulsion adhesives and coatings. It is also used as a cross-linking monomer for unsaturated polyester, modification of polyvinyl chloride and polypropylene, and as an intermediate for synthetic fragrances. Styrene is chloromethylated to obtain cinnamonyl chloride, which is used as an intermediate for the non-narcotic analgesic Diantadine. Styrene is also used as the original drug of the antitussive and expectorant drug Ixazine and the anticholinergic drug Wenchangning.

4. Used in the synthesis of styrene-butadiene rubber and polystyrene resin, polyester fiberglass and coatings, synthetic dye intermediate anthraquinone, pesticide emulsifier, medicine, mineral processing agent styrene phosphonic acid, etc.

5. Used to make polystyrene, synthetic rubber, ion exchange resin, etc. ^[31]

Modification of polyvinyl chloride and polypropylene, and used as an intermediate for synthetic fragrances. Styrene is chloromethylated to obtain cinnamonyl chloride, which is used as an intermediate for the non-narcotic analgesic Diantadine. Styrene is also used as the original drug of the antitussive and expectorant drug Ixazine and the anticholinergic drug Wenchangning.

4. Used in the synthesis of styrene-butadiene rubber and polystyrene resin, polyester fiberglass and coatings, synthetic dye intermediate anthraquinone, pesticide emulsifier, medicine, mineral processing agent styrene phosphonic acid, etc.

5. Used to make polystyrene, synthetic rubber, ion exchange resin, etc. ^[31]