Publication

2016

​Well-defined 4-arm stars with hydroxy-terminated polyethylene, polyethylene-b-polycaprolactoneand polyethylene-b-(polymethyl methacrylate)2 arms
Z. Zhang, Y. Gnanou, N. Hadjichristidis
Polym. Chem, 7, 5507, (2016)
Z. Zhang, Y. Gnanou, N. Hadjichristidis
Polyethylene, Star Polymer, Atom Trasnfer Radical Polymerization, Ring Opening Polymerization
2016

                                                               
       Bis-boron-thexyl-silaboracycle was prepared by hydroboration of 1,4-bis(methyldivinylsilyl)butane with thexylborane and used to initiate the polyhomologation of dimethylsulfoxonium methylide to afford welldefinedhydroxy-terminated 4-arm polyethylene (PE) stars. The synthesized PE stars were transformed to (PE-b-PCL)4 starblock copolymers via the ring-opening polymerization of ε-caprolactone (CL) initiated by the hydroxyl end groups of (PE-OH)4 in the presence of P2-tBu phosphazene base. Esterification of the hydroxyl groups of the OH-terminated PE star with 2,2-dichloroacetyl chloride led to (PE-Cl2)4 whichwas used as initiator (eight initiating atom transfer radical polymerization, ATRP, sites) for the synthesis of (PE-b-PMMA2)4 dendrimer-like stars by the ATRP of methyl methacrylate (MMA). All intermediates and final products were characterized by high temperature gel permeation chromatography and proton nuclear magnetic resonance spectroscopy.
 
 
                                                
 DOI: 10.1039/c6py01090c