Styrene → Styrene-butadiene-styrene

HRID 1278848Notes

Reaction equation

HRID 1278848 reaction equation
[CH2:1]=[CH:2][C:3]1[CH:8]=[CH:7][CH:6]=[CH:5][CH:4]=1.[CH:9]([Li])([CH2:11][CH3:12])[CH3:10].C([Mg]CCCC)CCC.C=CC=C>CCCCCC.C1CCCCC1>[CH2:1]=[CH:2][C:3]1[CH:8]=[CH:7][CH:6]=[CH:5][CH:4]=1.[CH2:10]=[CH:9][CH:11]=[CH2:12].[CH2:1]=[CH:2][C:3]1[CH:8]=[CH:7][CH:6]=[CH:5][CH:4]=1

Participants

7

Reactant 4

HCID 7501Styrene2×HCID 78451,3-ButadieneHCID 178418400CID 536281002×HCID 178448196HCID 178448196, compound

Product 1

HCID 22280236Styrene-butadiene-styrene

Reagents, catalysts & solvents 2

HCID 8058HexaneSolvent2×HCID 8078CyclohexaneSolvent

Conditions

Temperature
40 °C

Procedure

45 l of cyclohexane and 3 kg of styrene are introduced into a 100 l reactor fitted with wall cooling and additionally an external heat exchanger (tube-bundle heat exchanger) supplied by a pump, titrated against a 12% strength solution of sec-butyl-lithium in hexane until a pale red coloration remains and heated to 40° C. 140 ml of a solution, 12% strength in overall terms, of a mixture of 1 part by weight of s-butyllithium and 4 parts by weight of dibutylmagnesium in hexane are then added. The temperature remains at 40° C. A mixture of 14 g of butadiene and 3 kg of styrene is then added. Under these conditions, the temperature rises to 53° C. within 30 minutes. The styrene-butadiene-styrene block copolymer obtained has a tear strength of 24 MPa in the DIN 53455 tensile test. A molecular weight MW of 125,000 and a nonuniformity MW/MN of 1.15 are measured.

Workup

  1. customfitted with wall
  2. temperaturecooling
  3. temperatureadditionally an external heat exchanger (tube-bundle heat exchanger)
  4. additionare then added
  5. customremains at 40° C
  6. additionis then added

Sources & evidence

ORD record
ord-94f156882d984cd78ae13bb752fac2a2
Source dataset
uspto-grants-2002_09
Patent number
US06444762B1

Reaction notes

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