Methanol → 2-Methylbuta-1,3-diene;styrene

In a pressure resistant reactor, 23.3 kg of cyclohexane, 4.50 millimoles of N,N,N′,N′-tetramethylethylenediamine (hereinafter, referred to as TMEDA), and 1.33 kg of styrene were added, and while the mixture was stirred at 40° C., 151.5 millimoles of n-butyllithium was added thereto. While the temperature was elevated to 50° C., polymerization was carried out for one hour. The polymerization conversion ratio for styrene was 100% by weight. Subsequently, while the temperature was controlled to be maintained at 50° C. to 60° C., 7.00 kg of isoprene was continuously added to the reactor over one hour. After completion of the addition of isoprene, polymerization was carried out for another one hour. The polymerization conversion ratio for isoprene was 100%. Thereafter, 24.2 millimoles of tetrachlorosilane was added to the reactor as a coupling agent, and a coupling reaction was carried out for 2 hours. Thus, a branched styrene-isoprene-styrene block copolymer was formed, which would serve as a block copolymer Q. After this coupling reaction, 36.4 millimoles of methanol was added to the reactor as a polymerization terminator, and a polymerization termination reaction was carried out for one hour. Thus, the active terminal of a portion of the styrene-isoprene block copolymer having an active terminal was deactivated, and thereby a styrene-isoprene block copolymer was formed, which would serve as a block copolymer R. Subsequently, while the temperature was controlled to be maintained at 50° C. to 60° C., 1.67 kg of styrene was continuously added to the reactor over one hour. After completion of the addition of styrene, polymerization was carried out for another one hour, and thus a styrene-isoprene-styrene block copolymer was formed, which would serve as a block copolymer P. The polymerization conversion ratio for styrene was 100%. Subsequently, 303.0 millimoles of methanol was added thereto as a polymerization terminator, the resulting mixture was thoroughly mixed, and the reaction was terminated. The amounts of the various agents used in the reaction are summarized in Table 4. A portion of the reaction liquid thus obtained was taken out, and the weight average molecular weights of the respective block copolymers and the block copolymer composition, the weight average molecular weights of the respective styrene polymer blocks, the weight average molecular weights of the respective isoprene polymer blocks, the styrene unit contents of the respective block copolymers, the styrene unit content of the block copolymer composition, and the vinyl bond content of the isoprene polymer block were determined. These values are presented in Table 5. To 100 parts of the reaction liquid thus obtained (containing 30 parts of the polymer components), 0.3 part of 2,6-di-tert-butyl-p-cresol was added as an antioxidant and mixed with the reaction liquid. The mixed solution was added dropwise in small amounts into hot water which was heated to 85° C. to 95° C. to thereby volatilize the solvent, and a precipitate was thus obtained. This precipitate was pulverized and dried with hot air at 85° C. Thus, a block copolymer composition of Production Example 6 was collected.

1. additionwas added to the reactor as a polymerization terminator
2. customa polymerization termination reaction

ORD record

ord-b49243ab825c4c0597870738984fb098

Source dataset

uspto-grants-2013_08

DOI

10.6084/m9.figshare.5104873.v1

Patent number

US08501869B2