Two new org. phase-changing materials were prepd. by mixing Pr palmitate with Bu stearate (1:1 or 3:17 by mass), capsuled in a corm CH2 =CHOAc/alkyl acrylate copolymer and studied for stability of melting enthalpy and temp. after 2200 melting and solidification cycles in temp. range 10-50 degrees C. A com. alkane-based phase-changing material was used for comparison. The capsulation did result neither in any significant changes of enthalpy nor melting and solidification temps. of the new phase-changing materials studied but substantially contributed to stabilization of the com. phase-changing material.