  Using the self-consistent field lattice model, polymer concentration
$\bar{\phi}_{{P}}$ and chain length $N$ (keeping the length ratio of
hydrophobic to hydrophilic blocks constant) the effects on
temperature-dependent behavior of micelles are studied, in amphiphilic
symmetric ABA triblock copolymer solutions. When chain length is increased, at
fixed $\bar{\phi}_{{P}}$, micelles occur at higher temperature. The variations
of average volume fraction of stickers $\bar{\phi}_\textrm{co}^\textrm{s}$ and
the lattice site numbers $N_\textrm{co}^\textrm{ls}$ at the micellar cores with
temperature are dependent on $N$ and $\bar{\phi}_{{P}}$, which demonstrates
that the aggregation of micelles depends on $N$ and $\bar{\phi}_{{P}}$.
Moreover, when $\bar{\phi}_{{P}}$ is increased, firstly a peak appears on the
curve of specific heat $C_V$ for unimer-micelle transition, and then in
addition a primary peak, the secondary peak, which results from the
remicellization, is observed on the curve of $C_V$. For a long chain, in
intermediate and high concentration regimes, the shape of specific heat peak
markedly changes, and the peak tends to be a more broad peak. Finally, the
aggregation behavior of micelles is explained by the aggregation way of
amphiphilic triblock copolymer. The obtained results are helpful in
understanding the micellar aggregation process.
