Isoprene → HCID 19842620, compound

Participants

Reaction Conditions

Reaction Steps

To a pressure-resistant reactor, 23.3 kg of cyclohexane, 2.6 millimoles of TMEDA and 1.90 kg of styrene were added and stirred at 40° C. Added thereto was 172.9 millimoles of n-butyl lithium, and while the temperature was increased to 50° C., the mixture was polymerized for 1 hour. The degree of polymerization conversion of styrene was 100%. Subsequently, 8.10 kg of isoprene was added to the reactor continuously over 1 hour while the temperature was controlled to maintain 50 to 60° C. After the addition of isoprene was completed, the polymerization was performed for additional 1 hour. The degree of polymerization conversion of isoprene was 100%. Subsequently, 34.5 millimoles of tetramethoxysilane was added as a coupling agent and the coupling reaction was performed for 2 hours to form a branched styrene-isoprene-styrene block copolymer, which would be the block copolymer B. After that, 344.8 millimoles of methanol was added as a polymerization terminator to the solution in which the styrene-isoprene block copolymer having an active terminal remained and mixed well to terminate the reaction. Part of the reaction solution obtained was extracted and subjected to the same measurements as Preparation example 1. The values thereof are shown in Table 2. Subsequent treatments that were the same as those of Preparation example 1 were carried out to recover the block copolymer composition of Preparation example 5.

Provenance & Evidence