Hyperbranched poly(ether ether ketone)s: preparation and comparison of properties with the corresponding dendrimers

Hyperbranched poly(ether ether ketone)s with hydroxyl terminal groups are prepared by a one-step polycondensation of 3,5-dihydroxy-4'-(4-fluorobenzoyl)diphenylether (AB(2)-type monomer) through an aromatic nucleophilic substitution reaction. With the help of model compounds, H-1-NMR studies reveal that the degree of branching of the poly(ether ether ketone)s is about 52%. The possibility of entanglement among the hyperbranched polymer molecules is suggested from comparison of their glass transition temperatures with the corresponding dendrimers and the optimized structure of the hyperbranched polymers. The terminal hydroxyl groups were readily functionalized, yielding hyperbranched polymers with a variety of different functional chain ends. The nature of the chain end is shown to dramatically affect the properties of the hyperbranched polymers.