Styrene → Styrene-butadiene-styrene

Participants

Reaction Steps

In a 5 l jacketed autoclave equipped with a stirrer were charged 1667 g of cyclohexane, 12.1 mmol of sec-butyl lithium, and 4.5 mmol of N,N,N',N'-tetramethylethylene-diamine, and 250 g of a 30 wt % cyclohexane solution of styrene was added thereto. Polymerization was carried out at 75° C. To the reaction system, a 30 wt % cyclohexane solution of 1167 g of 1,3-butadiene and 250 g of a 30 wt % cyclohexane solution of styrene were added thereto, and polymerization was continued to obtain an SBS (styrene-butadiene-styrene) terblock copolymer. Two percent of the sec-butyl lithium was deactivated with a trace water content, leaving 11.9 mmol of active lithium. To the resulting living polymer solution was added 12.37 mmol of ethanol to deactivate the polymer terminals.

Provenance & Evidence