Styrene → Styrene-butadiene-styrene

Participants

Reaction Steps

4800 g of cyclohexane was placed in a 10 l autoclave reactor, followed by the addition of 11 g of tetrahydrofuran, 124 g of styrene monomer and 16 mmol of n-butyl lithium for 30-minute polymerization. Then, 552 g of 1,3-butadiene monomer were added to the reactor for another polymerization for 1 hour. Also, 124 g of styrene monomer were added for further polymerization for 30 minutes, followed by the addition of 1.5 g of t-butyl chloride to deactivate the terminal of polymer. Thus, a styrene-butadiene-styrene block copolymer, so obtained, had the following characteristics: 31.0% as a combined content of styrene (block styrene content: 30.0%), 38.5% as a combined 1,2 vinyl content of butadiene unit, and a number average molecular weight of about 50,000.

Provenance & Evidence