As the temperature of Pluronic copolymer solutions increases, the copolymer molecules evolve from a region with only monomers, monomer only, to a region where monomers are in equilibrium with micelles, monomer − micelle, to a region where only micelles are found, micelle only. In this article, we analyze the concentration dependence (0.1−10% w/w) of the reduced viscosity, ηred, the apparent specific volume, v p, φ, and the apparent specific heat capacity, cpp, φ, in terms of these regions at 5, 25, and 45 °C. Six Pluronics (F38, P85, P104, P103, L122, and L101) have a molecular weight around 5000 g·mol-1 and two (F108 and P105) have a higher molecular weight. The method compares the apparent specific volume and heat capacity of the copolymer in solution with its additive values corresponding to the monomeric state (v mono and cpmono). If v p, φ ≈ v mono and cpp, φ ≈ cpmono, then all the copolymer molecules are in the monomeric state. If v p, φ ≳ v mono and cpp, φ > cpmono, then the copolymer molecules are in equilibrium with micelles. Finally, if v p, φ > v mono and cpp, φ ≈ cpmono, then the copolymer molecules are all in the micellar state. At 5 °C, all the Pluronics studied are in the monomeric state between 0.1 and 10 g/mL. At 25 °C, the monomer only, monomer − micelle, and micelle only regions are all encountered depending on the molecular weight and the polyoxypropylene content. At 45 °C, F38 is still in the monomeric state and P85 molecules are in equilibrium with monomer only at low concentrations. All the other copolymers investigated form only micelles. The investigation of the apparent specific volume and heat capacity has proven quite sensitive, in particular for the identification of the concentration range where monomers are in equilibrium with micelles.