Fluoride-ion induced polycondensation of dibromocompounds with several dibasic acids

Abstract

The monomer containing carbonyl group, bis(4-bromoacetyl phenyl)methane was synthesized by the Friedel-Crafts reaction of biphenylmethane with acetyl chloride followed by bromination. The other monomers containing carbonyl group, such as bis(4-bromoacetyl phenyl) and bis(4-bromoacetyl phenyl)ether were synthesized by the Friedel-Crafts reaction of biphenyl and biphenyl ether with bromoacetyl chloride. These monomers were polycondensed with several dibasic acids such as malonic, succinic, glutaric, adipic and terephthalic acid to obtain polymers containing ketone and ester group. The monomers were polycondensed in N,N``-dimethylformamide in the presence of potassium fluoride as catalyst at $40\,^\circ\!C$ for an hour. Polymerization yields were 90-99\%. The structures of the several monomers and resulting polymers were characterized by IR and H$^1$-NMR spectroscopy. IR spectrum of monomers showed characteristic absorption band at $3050-3100 cm^{-1}$ (aromatic C-H stretching) and $1700-1720 cm^{-1}$ (C=O stretching), those of resulting polymers were observed at $3100 cm^{-1}$ (aromatic C-H stretching) and $1680-1750 cm^{-1}$ (C=O stretching of ketone and ester group) region. The physical properties of such as DSC, TGA and inherent viscosity were also investigated.