Hyperbranched Poly(aryl ether oxazole)s:  Synthesis, Characterization, and Modification

Abstract

In this paper the synthesis and characterization of a hyperbranched poly(aryl ether oxazole) with terminal phenolic groups are described. An ABB‘ monomer containing a pair of phenolic groups and an aryl fluoride which is activated toward displacement by the attached oxazole ring was prepared. The nucleophilic substitution of the fluoride with the phenolic group leads to the formation of ether linkage and subsequently the hyperbranched poly(aryl ether oxazole) P1. As determined by a combination of model compound studies and 1H NMR integration experiments, the degree of branching of P1 is approximately 50%. The polymer P1 is thermally stable and readily soluble in polar organic solvents. The terminal phenolic groups in P1 were easily functionalized, yielding hyperbranched polymers with a variety of functional chain ends. Physical properties, such as the glass transition temperature and the solubility of the hyperbranched poly(aryl ether oxazole)s, depended significantly on the nature of the chain ends.

Synthesis and Characterization of Hyperbranched Poly(arylene ether)s from a New Activated Trifluoro B3 Monomer Adopting an A2 + B3 Approach

“…[1] In addition to common electronwithdrawing groups such as sulfone and ketone, certain heterocycles can activate aryl halides toward aromatic nucleophilic substitution. Several hyperbranched poly(arylene ether)s have been reported in the literature from AB 2 monomers that include poly(ether sulfone), [10] poly(ether ketone)s, [11][12][13][14] poly(etheroxazole), [15] poly ( A new trifluoromethyl-activated trifluoro monomer was successfully prepared by Pd-initiated coupling of 1,3,5-tribromobenzene with 4-fluoro-3-trifluoromethylphenylboronic acid. 1,3,5-Tris(4-fluoro-3-trifluoromethylphenyl)benzene (B 3 ) leads to several hyperbranched poly(arylene ether)s when reacted with three different bisphenols (A 2 ) in different molar ratios.…”

Novel hyperbranched poly(phenylene oxide)s with phenolic terminal groups: synthesis, characterization, and modification

“…Modification of the peripheral groups on hyperbranched polymers significantly influences their physical properties [13,14], which provides a possibility toward larger scale potential applications. Now many hyperbranched poly(arylene ether)s have been reported, such as poly(ether sulfone) [15], poly(ether ketone) [16,17], poly(ether oxazole) [18], and poly(ether phenyl quinoxaline) [19][20][21]. However, the reactive monomers for these hyperbranched polymers contain electron-withdrawing groups, which facilitate aromatic nucleophilic substitution reactions.…”

Aromatic Hyperbranched Polymers: Synthesis and Application

“…Hyperbranched Poly(aryl ether)s with Oxazole, Oxadiazole, and Oxindole Moieties Gong et al [173] synthesized and characterized an ABB 0 -type monomer containing a pair of phenolic groups and an aryl fluoride, which was activated toward displacement by the attached oxazole ring. The ABB 0 monomer (1-34, Scheme 12) was self-condensed to form a hb poly(aryl ether oxazole) (hb-PAE-Ox) with terminal phenolic groups.…”