## 3 Result and Discussion
### Property of Polymer Micelles  
The polymers in the above prepared aqueous-solutions were observed using dynamic-light-scattering (DLS) measurements. BL-02, BL-04, and BL-05 showed small sizes of around 10 nm, and BL-01 and BL-03 showed sizes of around 20-30 nm, as summarized in Figure 4 and Table 5. This showed that all polymers were well dispersed in water. Because BL-02 can be directly dissolved in aqueous solution, BL-02 polymer-states in aqueous solution can be compared with and without utilizing pre-solutions of DEG. As a result, the sizes were almost equal. However, from the viewpoint of D, the scheme of using the DEG solution yielded a smaller value, emphasizing this scheme's benefit too. Note that these sizes would be larger than the assumed sizes of single polymers having a molecular weight of around 2000-4000 Da. It is expected that they are molecularly dispersed and self-assembled as polymer micelles in aqueous milieu. This is further suggested by the following critical-micellization-concentration (CMC) measurement. \begin{table}
\begin{tabular}{c c c c c c} \hline \hline
**Sample** & **Monomer** & \multicolumn{2}{c}{**Solubility * in**} & \multicolumn{2}{c}{**MEK Solution**} & \multicolumn{1}{c}{**DEG Solution**} \\ \hline  & & **MEK** & **DEG** & \(\rightarrow\)**KOHaq ** & \(\rightarrow\)**KOHaq ** \\ \hline BL-01 & St, DPE, MAA, & Soluble & Soluble (110 \({}^{\circ}\)C) & Insoluble & Soluble \\ BL-02 & St, DPE, \(n\)-BMA, MAA & Soluble & Soluble (50 \({}^{\circ}\)C) & Insoluble & Soluble \\ BL-03 & St, \(\alpha\)-MeSt, MAA & Soluble & Soluble (50 \({}^{\circ}\)C) & Insoluble & Soluble \\ BL-04 & St, \(\alpha\)-MeSt, MAA & Insoluble & Insoluble & - & \\ BL-05 & St, \(\alpha\)-MeSt, MAA & Soluble & Soluble (90 \({}^{\circ}\)C) & Insoluble & Soluble \\ \hline \hline \end{tabular}  
* 28 wt\(\%\). ** 0.1 wt\(\%\), 1.2 times the excess molar of KOH, compared to that of the carboxyl groups in polymers, were added to the polymers.  
\end{table} 
Table 4: Polymer solubility in the KOH solution from the solvent solution. Figure 3: From left to right: (**a**) BL-03 aqueous solution from DEG solution (reference), BL-03 in 0.3% DEG aqueous solution, BL-03 in 0.5% DEG aqueous solution, BL-03 in 0.9% DEG aqueous solution; (**b**) BL-05 aqueous solution from DEG solution (reference), BL-05 in 0.3% DEG aqueous solution, BL-05 in 0.5% DEG aqueous solution, BL-05 in 0.9% DEG aqueous solution. For the investigation of the polymer dispersant behavior in the aqueous solutions, the diluted polymer solutions in the varied concentrations were evaluated with the addition of pyrene as a fluorescence probe. The amphiphilic polymers generally have CMC [23; 24; 25; 26; 27], and polymer micelles are formed at concentrations over CMC. Formation of the micelles can be detected from the change in the fluorescence-intensity ratio of the first and third vibronic-emission-bands of the added pyrenes, \(I_{1}(374\) nm)/\(I_{3}(385\) nm), because the pyrene-fluorescence fine structure is markedly dependent on the solvent [28], such that the intensity ratio of \(I_{1}/I_{3}\) is sensitive to the solvent polarity: the \(I_{1}/I_{3}\) values decrease with decreasing solvent polarity. When the polymer micelles are formed in aqueous solution, the pyrene molecules enter the hydrophobic core of the micelle, eventually declining in the polarity of the pyrene microenvironment, to observe a decrease in the \(I_{1}/I_{3}\) values. As shown in Figure 5, all series of polymers showed the decrease in \(I_{1}/I_{3}\) values, indicating they all have CMC, and agreeing with the DLS results by detecting the polymer micelles at 0.1 wt% polymer concentration. The polymer series, except for BL-04, showed a decrease in \(I_{1}/I_{3}\) values at concentrations over 0.0001 wt%, and the BL-04, where the acid values were as high as 271, showed a decrease in that at 0.001 wt%.