Styrene → Styrene

Participants

Reaction Steps

After a first addition of styrene, the mixture was polymerized for 15 minutes. A second addition of initiator (s.-BuLi 2) was made to initiate new polymer chains, and further styrene was added in portions to continue block build-up. The reaction time for build-up of a styrene block was 15 minutes, and that for a butadiene block was 40 minutes. The polymerization was terminated by adding 3 mL of isopropanol. 0.1% by weight of Kerobit TBK (2,6-di-tert-butyl-p-cresol), based on the solids content of the block copolymer, was added for stabilization. Table 4 gives the amounts of styrene, butadiene, and sec-butyllithium used in each of the stages, and also gives the properties of the resultant block copolymer mixtures.

Provenance & Evidence