Acrylic Acid → 5-Phenyl-2,4-pentadienoic acid

Participants

Reaction Conditions

Reaction Steps

Into a polymerization reactor equipped with an agitator and a reflux condenser were charged 580 grams of styrene, 3.0 grams of terpenolene and 200 ml of ethylbenzene. Then 80 grams of high cis-polybutadiene from Goodyear Tire & Rubber Company (Budene 1208) was dissolved in the mixture. After the rubber had dissolved, a solution of 40 grams of acrylic acid in 60 ml of methyl ethyl ketone (335 ml) was introduced into the mixture. The temperature of the reaction mixture was raised to 85° C. and maintained at this level during the ensuing polymerization. Polymerization was initiated by introducing into the system a mixture of 0.2 ml of tert-butyl peracetate and 0.2 ml of tert-butyl per-neo-decanoate. One hour later, continuous addition of a solution of 40 grams of acrylic acid and 60 ml of methyl ethyl ketone was initiated and this addition was continued over a four hour period. At one hour and again at four hours after the start of the continuous addition of the acrylic acid solution, additional 0.2 ml portions of tert-butyl peracetate were introduced into the polymerization mixture. Polymerization was terminated 5.5 hours after initiation and the resultant polymer was recovered and dried, first in air and then in a vacuum oven, to yield 432 grams of rubber-modified styrene-acrylic acid graft copolymer. In order to produce enough copolymer for the compounding and ensuing test work this polymerization procedure was repeated four more times and the products from the five runs were combined and mixed in a Waring blender. The resultant polymer contained about 84.2 weight percent styrene and about 15.8 weight percent acrylic acid. Its rubber content was approximately 18.5 percent based on the weight of the resin phase.

Provenance & Evidence