Preparation of Octa-Arm Polyisobutylenes

Polymerizations were carried out either in 75-ml culture tubes or in 250-ml stirred reactors in two stages according to a published procedure [61, 62]. In 

The overall methodology of IB polymerization by the two-stage procedure has been followed (see Sect. 2.2.1). The terminal allyl-functionahzation of the hving PIB arms was carried out by adapting a procedure developed in these laboratories [63]. Allyltrimethylsilane (ATMS) ( 100-fold excess relative to the PIB chain end) was added when IB conversion has reached 95%. After 60 min the polymerization mixture was poured into an excess of chilled methanol, the product separated, redissolved in hexanes, washed with water and methanol, and finally reprecipitated into methanol. 

Preparation of Octa-Arm Poly(styrene-b-isobutylene) Stars 

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