The equilibrium thermodynamic properties and crystallization behavior of po
ly(p-phenylene succinate) (PPSc) were examined using differential scanning
calorimetry (DSC) and a wide-angle X-ray diffractometer. When PPSc quenched
into liquid nitrogen, the PPSc still showed 60 J/g of the heat of fusion,
indicating that PPSc crystallizes too fast to be quenched to a glassy state
. The equilibrium heat of fusion (Delta H degrees) of PPSc and its equilibr
ium entropy of fusion (Delta S degrees) were estimated to be 28 and 48 J/mo
l K, respectively. The effect of the molecular weight and undercooling on P
PSc crystallization was analyzed by the Avrami expression. The crystallizat
ion rate of PPSc was highest at about 276 degrees C, regardless of molecula
r weight when the sample was isothermally crystallized. This temperature wa
s higher than that of poly(ethylene terephthalate) (PET) by 100 degrees C.
The crystallization rate was highest when the number average molecular weig
ht of PPSc was about 20,000 g/mol. (C) 1999 John Wiley & Sons, Inc.