## 3 Results and Discussion  
### Description  
The physicochemical properties of the ionic liquid-modified magnetic polymers are shown in Table 1. It can be seen that the substance has a large specific surface area, which can effectively increase the contact area between the dye and the polymer, improving the absorption effect of the dye. The surface morphology of \(\gamma\)-Fe\({}_{2}\)O\({}_{3}\)@GMA@IM is shown in Figure 2. Due to the existence of the inorganic magnetic powder \(\gamma\)-Fe\({}_{2}\)O\({}_{3}\), the surface of the magnetic polymer is relatively rough, with many irregular protrusions and some concave holes on the surface of the polymer, corresponding to its larger specific surface area. The FTIR of \(\gamma\)-Fe\({}_{2}\)O\({}_{3}\)@GMA and \(\gamma\)-Fe\({}_{2}\)O\({}_{3}\)@GMA@IM are shown in Figure 3. The stretching vibration peak of Fe-Ois 578 cm\({}^{-1}\). The \(-\)CH=CH\({}_{2}\) characteristic absorption peak at 1630 cm\({}^{-1}\) of the synthesized monomer GMA disappeared after the preparation of the magnetic polymer, proving the successful progress of the polymerization reaction [21]. The absorption peak at 903 cm\({}^{-1}\) originated from the epoxy group of the polymer, which disappeared after the grafting reaction. For \(\gamma\)-Fe\({}_{2}\)O\({}_{3}\)@GMA@IM, its absorption peaks at 940 cm\({}^{-1}\) and 1169 cm\({}^{-1}\) are C-N stretching vibrations of imidazole groups and C=N stretching vibrations at 1570 cm\({}^{-1}\)[22]. In addition, \(\gamma\)-Fe\({}_{2}\)O\({}_{3}\)@GMA@IM forms a strong \(-\)OH characteristic absorption peak at 3400 cm\({}^{-1}\), which also confirms that the epoxy groups of the polymer \(\gamma\)-Fe\({}_{2}\)O\({}_{3}\)@GMA are opened during the grafting process, and -OH is formed [23]. \begin{table}
\begin{tabular}{c c} \hline \hline
**Parameters** & \(\gamma\)**-Fe\({}_{2}\)O\({}_{3}\)@GMA@IM** \\ \hline Matrix structure & Acrylic \\ Water content (\%) & 55–60\% \\ Diameter (\(\mu\)m) & 50 \\ Average pore size (nm) & 3.421 \\ BET specific surface area (m\({}^{2}\)/g) & 14.703 \\ Total pore volume (cm\({}^{3}\)/g) & 0.042 \\ \hline \hline \end{tabular}
\end{table} 
Table 1: Physicochemical parameters of \(\gamma\)-Fe\({}_{2}\)O\({}_{3}\)@GMA@IM. Figure 2: SEM image of \(\gamma\)-Fe\({}_{2}\)O\({}_{3}\)@GMA@IM. According to the XRD patterns of \(\gamma\)-Fe\({}_{2}\)O\({}_{3}\)@GMA@IM and \(\gamma\)-Fe\({}_{2}\)O\({}_{3}\) shown in Figure 4, the magnetic polymer has a broad peak in the range of 10\({}^{\circ}\)-25\({}^{\circ}\) at 20, which is the characteristic peak of the amorphous material, which should be the polymer group generated. In contrast to standard PDF cards (39-1346), absorption peaks corresponding to (220), (311), (400), (422), (551) and (440) crystal faces at 20 = 30.36\({}^{\circ}\), 35.72\({}^{\circ}\), 43.40\({}^{\circ}\), 53.84\({}^{\circ}\), 57.48\({}^{\circ}\), 63.02\({}^{\circ}\), further confirming that the crystal form of \(\gamma\)-Fe\({}_{2}\)O\({}_{3}\) did not change with the reaction. The hysteresis loops of \(\gamma\)-Fe\({}_{2}\)O\({}_{3}\) and \(\gamma\)-Fe\({}_{2}\)O\({}_{3}\)@GMA@IM are shown in Figure 5. The specific saturation magnetization of \(\gamma\)-Fe\({}_{2}\)O\({}_{3}\) is 63.725 emu/g, and the specific saturation magnetization of \(\gamma\)-Fe\({}_{2}\)O\({}_{3}\)@GMA@IM is 10.211 emu/g. This is due to the reduction in the specific saturation magnetization of the magnetic polymer caused by the organic matter wrapped around the \(\gamma\)-Fe\({}_{2}\)O\({}_{3}\). On the other hand, because the magnetic polymers have a relatively high remanence and coercivity, and thus a permanent magnetism, they can attract  
Figure 4: The XRD pattern of \(\gamma\)-Fe\({}_{2}\)O\({}_{3}\)@GMA@IM. each other, agglomerate and rapidly settle in the absence of an external magnetic field, and the separation effect is good. Figure 6 shows the thermal stability of \(\gamma\)-Fe\({}_{2}\)O\({}_{3}\)@GMA@IM.