Oxygen → HCID 20233174, compound

Participants

Reaction Steps

A 1-liter flask was charged with 506 grams of α-methylstyrene. The α-methylstyrene was then treated with 0.56 millimole of secondary butyllithium to inactivate residual moisture, oxygen and other impurities. 60 Grams of 1,3-butadiene together with 18 grams of styrene and 0.62 millimole of secondary butyllithium were added to the flask in that order. The flask was placed in a water bath having a temperature which vaired from about 45° to 60° centigrade and served to maintain the polymerization temperature. After a period of 51/2 hours, the contents of the vessel became red in color. The temperature rose about 10° above that of the water bath indicating the beginning of polymerization of the styrene and α-methylstyrene copolymer block. The contents of the flasks were maintained at a temperature above about 60° C. for an additional 30 minutes after the appearance of the red coloration. 2 Milliliters of methanol were added to the reaction mixture to terminate the active polymer chains. Polymer was recovered from the reaction mixture by precipitation in methanol. Gel permeation chromatography was employed to determine the molecular weight of the product which was 350,000 grams per mole.

Provenance & Evidence