In the present work, temperature dependence of heat capacity of the block copolymer based on hyperbranched perfluorinated poly(phenylenegermane) and atactic polystyrene has been measured first in the range from 6 to 350 K and between 320 and 534 K, respectively, by precision adiabatic vacuum and dynamic calorimetry. In the above temperature ranges, the devitrification of constituent blocks was detected and its thermodynamic characteristics have been determined and analyzed. The experimental data were used to calculate standard thermodynamic functions, namely the heat capacity C-p degrees(T), enthalpy H degrees(T) - H degrees(0), entropy S degrees(T) - S degrees(0) and Gibbs function G degrees(T) - H degrees(0), for the range from T -> 0 to 518 K. The standard thermodynamic properties of the said substance were compared with corresponding data for the initial homopolymers as well as for the block copolymer on basis of hyperbranched perfluorinated poly(phenylenegermane) and atactic poly(methylmeth)acrylate studied earlier. (c) 2008 Published by Elsevier B.V.