Synthesis and characterization of organosoluble thermally stable polyamides containing spacer methylene linkage and bulky tetraphenylfuran moiety

Abstract

Thermally stable and organo-soluble polyamides synthesized by polycondensation reaction of diacid monomer, 2, 5-bis (4-carboxymethylene phenyl) 3, 4-diphenyl furan (BCMPDF) with various commercially available aromatic diamines such as 4,4′-Oxydianiline, 4,4′-methylenedianiline, 4,4'-sulphonyldianiline, 4,4'-Diaminobenzophenone and 4,4'-(hexafluoroisopropylidene)dianiline by using Yamazaki’s direct phosphorylation method. A 2, 5-bis (4-carboxymethylene phenyl) 3, 4-diphenyl furan (BCMPDF) as a new compound containing methylene linkage and bulky moiety of tetraphenylfuran was successfully prepared by a four step reaction. The resulted polymers show excellent thermal stability, good solubility in aprotic polar solvent and inherent viscosities between 0.50 and 0.58 dl/g. Wide angle X-ray diffraction of all these PAs show amorphous nature. Polyamides showed glass-transition temperatures in the range of 169–213 °C indicate that polymers are easily processable. Thermogravimetric analysis of the polyamides indicated a 10% weight loss (T10) in the temperature range of 449–510 °C and char yields at 900 °C under nitrogen atmosphere in the range of 49–58% depending on the diamine monomer used for the synthesis polyamides. The structure -property correlation among these polyamides were discussed. The limiting oxygen indexes of all polyamides are more than 37.1, thus such type polymers of can act as flame retardant materials. These polyamides will be useful for high performance applications.