By dynamic calorimetry the temperature dependences of heat capacity of phenylated polyphenylene (PPPh) and 1,4-bis-(2,4,5-triphenylcyclopentadienone- 3-yl) benzene (TPCPB) in the range 300-640 K at standard pressure have been determined within 1.5%. The thermodynamic characteristics of fusion of TPCPB, namely temperature, enthalpy and entropy, as well as the parameters of glass transition and glassy state for PPPh such as temperature, zero entropy of glassy state, the difference in zero enthalpies of glassy and crystalline states have been estimated. The experimental data obtained in the present work and literature findings were used to calculate their thermodynamic functions: the heat capacity C-p(o) (T), enthalpy H-o(T) - H-o(0), entropy S-o(T) and Gibbs function G(o)(T) - H-o(0) over the range from T --> 0 to 640 K. The thermodynamic characteristics of synthesis reaction of phenylated polyphenylene have been evaluated between 0 and 600 K. (C) 2004 Elsevier B.V. All rights reserved.