Six novel polyamides, incorporating triarylphosphine oxide groups and aliph
atic bridging units, have been prepared. Of these, three were synthesised b
y a direct melt condensation reaction of bis(4-carboxyphenyl)phenylphosphin
e oxide (p-BCPPO) with a series of aliphatic diamines. A phosphorylation po
lycondensation method was used to prepare three polymers from bis[4-(3-amin
ophenoxy)phenyl] phenylphosphine oxide (m-BAPPO) and a series of aliphatic
dicarboxylic acids. The thermal properties of all polyamides were investiga
ted by differential scanning calorimetry and thermogravimetric analysis. Si
gnificantly different results were obtained for the two series. Glass trans
ition temperatures (T-g) in the 215-235 degrees C range, together with good
thermooxidative stabilities (5% weight loss occurring at > 420 degrees C)
and high char yields upon prolonged heating at 700 degrees C (40-44%) were
observed for the polyamides synthesised from m-BAPPO. The polymers prepared
from p-BCPPO incorporated longer aliphatic bridging units and, consequentl
y, demonstrated lower T-g values (184-205 degrees C) and reduced thermooxid
ative stability (5% weight loss occurring at > 370 degrees C). Good solubil
ity in aprotic polar solvents was observed for all polyamides. Additionally
, those with -(CH2)(5)- and -(CH2)(6)- units within the polymer backbone we
re partially soluble (0.1-1.0%) in several common organic solvents, such as
chloroform and acetone. (C) 1998 Elsevier Science Ltd. All rights reserved
.