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

Participants

Reaction Conditions

Reaction Steps

700 grams of cyclohexane containing 100 ppm of tetrahydrofuran and 18 g of styrene monomer were charged to a reactor of 2 litres of capacity, of stainless steel, equipped with thermostatting jacket and stirring system. The mixture was heated up to 50° C. and then 0.09 g of n-butyl-lithium in solution in n-hexane was added to it. After 25 minutes of reaction, the temperature had increased up to 55° C. A sample was collected in order to check the reaction mixture for the complete conversion of the monomer into polymer and measure the molecular weight, then 72 g of isoprene was added and the polymerization was allowed to proceed during 20 minutes; after that time period, the second monomer was completely converted. The temperature of the mixture resulted to be of approximately 90° C. Thus, a living diblock styrene-isoprene (S-I) polymer was obtained, which was then submitted to coupling in order to form a three-arm radial polymer.

Provenance & Evidence