Poly(β‐pinenes) carrying one, two, and three functional end groups. II. Syntheses and characterization

Conditions for the convenient synthesis of linear poly(β‐pinenes) that carry one or two tert‐chloro end groups (∼Cl t ) and three‐arm star poly(β‐pinenes) that carry three termini have been worked out. Specifically, the polymer with one ∼Cl t end group was prepared by the H 2 O/BCl 3 system, whereas those with two and three ∼Cl t termini were prepared by the use of p ‐dicumyl chloride and sym‐tricumyl chloride/BCl 3 inifer combinations. The ∼Cl t ‐terminated polymers were dehydro‐chlorinated to yield the corresponding olefins. The molecular weights of the products were low enough to permit infrared (IR) and quantitative 1 H‐NMR investigations. Poly(β‐pinene‐ b ‐tetrahydrofuran) diblock copolymers have been synthesized by inducing the polymerization of tetrahydrofuran (THF) by the PβCl t /AgCF 3 SO 3 initiating system.