## 4 Conclusions  
The suspension polymerization of styrene and nBA in the presence of four CNTs (CNT-A nonmodified, CNT-B nonmodified with short chain, CNT-C modified with NH\({}_{2}\), and CNT-D modified with boron) at different concentrations (varying between 0.065 wt% and 0.1 wt%) was investigated with the aim of selecting the best CNT for use as a pigment to produce particles for toner applications. Among those investigated, the only successful CNT was that modified with boron which achieved the best conversion and encapsulated particles for all concentrations. The remaining types were not effective enough to obtain high conversion or large particle sizes, even with very low CNT concentrations.  
Various concentrations of the CNTs modified with boron (CNT-D) were investigated with the aim of selecting an optimum concentration for toner materials. Of the various CNT concentrations, 0.25 wt% showed good results concerning conversion, particle size, and encapsulation. CNT-D with a concentration of 0.25 wt% was used in the suspension polymerization of styrene and nBA in the presence of a CCA. Two types of CCA were tested: one dissolved in styrene (MEC-88), the other in acetone or ethanol (MEP-51). With MEC-88, it was not possible to reach a desirable conversion for all concentrations, and this is attributed to the retarding/inhibiting effects of mainly carbonyl groups. In contrast to the MEC-88 results, it was possible to achieve a high conversion rate (above 90%) with all concentrations of MEP-51 (except for the highest 0.1 wt%) when ethanol was used as the solvent instead of acetone, which did not show good conversion. Furthermore, SEM micrographs demonstrated that particle sizes were in the micron range, which was in agreement with DLS measurements, and that CNT attachment to the polymerized particles was good. The images demonstrated the uniformity of the particles achieved with the lowest concentration of MEP-51; as the concentration increases, particle uniformity decreases. In addition, the CNTs were seen to be attached to the cores of the particles.  
The following supporting information can be downloaded at: [[https://www.mdpi.com/article/10.3390/ma16113941/s1](https://www.mdpi.com/article/10.3390/ma16113941/s1)]([https://www.mdpi.com/article/10.3390/ma16113941/s1](https://www.mdpi.com/article/10.3390/ma16113941/s1)), Figure S1: Dispersion of CNT-A in water (left) and in chloroform (right), one week after sonication.; Figure S2: SEM micrographs of CNT-A dispersed in (a) Chloroform and (b) water.; Figure S3: SEM micrographs of SP-CNT-B at two different scales: (a) 2 \(\upmu\)m and (b) 500 nm.; Figure S4. SEM micrographs of CNT-D attached to polymerized particles with two different concentrations (0.75% and 0.5%) and two different scales (10 and 5 \(\upmu\)m).  
Conceptualization, A.A.B., O.A.A. and E.M.A.; methodology, A.A.B. and O.A.A.; software, E.M.A.; validation, A.A.B. and E.M.A.; formal analysis, E.M.A.; investigation, A.A.B.; resources, E.M.A.; data curation, E.M.A.; writing--original draft preparation, E.M.A.; writing--review and editing, A.A.B. and E.M.A.; visualization, E.M.A.; supervision, A.A.B.; project administration, A.A.B.; funding acquisition, A.A.B. All authors have read and agreed to the published version of the manuscript.  
The authors express great appreciation to King Abdulaziz City for Science and Technology (KACST) for funding this project.  
Not applicable.  
The are no linked research datasets for this submission. Data will be made available on request.