M. Shibata et al., THERMAL-PROPERTIES AND CRYSTALLIZATION BEHAVIOR OF POLY(ETHER ETHER KETONE KETONE) POLY(ETHER BIPHENYL ETHER KETONE KETONE) COPOLYMERS, Macromolecular chemistry and physics, 197(10), 1996, pp. 3167-3175
Thermal properties of poly(ether ether ketone ketone) (PEEKK)/poly(eth
er biphenyl ether ketone ketone) (PEDEKK) copolymers were investigated
by me:ans of differential scanning calorimetry (DSC) and thermogravim
etric analysis (TGA). The glass transition temperature (T-g) increases
from 154 degrees C to 183 degrees C as the content of PEDEKK units in
creases. The melting point (T-m) of the copolymers varied in the range
between 314 degrees C and 409 degrees C and showed the behavior of eu
tectic type copolymer. From the investigation of the crystallization b
ehavior of the copolymers, it was found that the cold-crystallization
temperature (T-c') of the amorphous copolymers assumes a maximum value
for the copolymer with a mole fraction of the PEDEKK segment (n(B)) o
f about 0.6, isothermally crystallized PEEKK and the PEEKK/PEDEKK copo
lymer exhibit double-melting behavior.