# Ionic Liquid-Modified Porous Organic Polymers as Efficient Metallocene Catalyst Supports
## 3 Results and Discussion
### Pore Structure of Ionic Liquid-Modified Porous Organic Polymer  
According to Table 1, the prepared IL-POPs exhibit good porosity and are quite different with different comonomer contents. The value of SSA ranges from 16.9 m\({}^{2}\)/g to 561.8 m\({}^{2}\)/g, and the TPV ranges from 0.08 cm\({}^{3}\)/g to 0.71 cm\({}^{3}\)/g, and the PD ranges from 3.08 nm to 18.90 nm.  
The influence of [BVIM] [CI] contents on the formation of pore structure of the IL-POPs with mono-function-group was investigated. As shown in Table 1, while the [BVIM] [CI] adding amount was only 5%, POP-5 was poorly porous with 47.8 m\({}^{2}\)/g of SSA, the NLDFT simulated PD was 6.80 nm that the obtained pores exhibited low surface area and pore volume, and the TPV was only 0.08 cm\({}^{3}\)/g. When increasing the [BVIM] [CI] adding amount to 33%, POP-2 obtained a higher porosity than POP-3 (FC content = 25%) and POP-6 (FC content = 20%) with the SSA value of 550.1 m\({}^{2}\)/g, 496.0 m\({}^{2}\)/g and 331.5 m\({}^{2}\)/g, respectively. According to Figure 2b, POP-2 contained more larger pores (PD > 4 nm) than POP-3 and POP-6, and the cumulative pore volume of POP-2 was higher than the others. It can be seen from Figure 2c that, in the pore size range of 1 nm to 4 nm, pores with high surface area of POP-6 were less than POP-2 and POP-3, then POP-6 obtained lower cumulative surface area. The polarity of prepared IL-POPs was changed by adjusting the FC content, thus the thermodynamic compatibility between solvent system and polymers was changed. Furthermore, we can infer that the pores with larger PD (>4 nm) contribute more to the TPV, while pores with smaller PD (1 nm < PD < 4 nm) contribute more to the SSA. POP-4, with the [BVIM] [CI] adding amount at 40%, was also highly porous with relatively higher SSA, TPV and PD value than POP-2. As shown in Figure 2b, in the range of PD above 4 nm, POP-4 obtained larger pore volume than POP-2, then the TPV value was higher than POP-2 as a result. However, when the [BVIM] [CI] adding amount was increased to 50%, an almost nonporous structure was acquired that the SSA of POP-1 decreased sharply to 16.9 m\({}^{2}\)/g, which could be explained by the poor thermal compatibility.  
Figure 1: Preparation of ionic liquid-modified POPs.  
Compared to POP-6, POP-7 was synthesized in the solvent system of EtOH/H\({}_{2}\)O (V:V = 9:1) and the prepared particles were less porous than POP-6. Therefore, the deion  
Figure 2: (**a**,**d**) N\({}_{2}\) sorption isotherms of IL-POPs prepared with different functional comonomer contents; (**b**,**e**) NLDFT simulated pore-size distribution curves of dV (d) vs. d; (**c**,**f**) NLDFT simulated pore-size distribution curves of dS (d) vs. d.  
ized water has a negative effect on the formation of pores with high surface area and pore volume, which can be ascribed to the thermodynamic compatibility change.  
As for the ternary system with [BVIM] [Cl] and HEMA as dual functional comonomers, the prepared IL-POPs also obtained tunable pore structure and POP-9 exhibited best both in SSA and TPV. When the total FC content decreased from 43% to 25%, the SSA of POP-9 increased to 506 m\({}^{2}\)/g from 139 m\({}^{2}\)/g of POP-8. From Figure 2f, it is obvious that in the pore size range of 1 nm to 10 nm, POP-8 was almost non-porous. When increasing the DVB to [BVIM] [Cl] ratio from 4:1 to 6:1 that the cross-linking degree of prepared IL-POPs was changed, compared to POP-10, the SSA and TPV of POP-9 was increased a little. POP-11 obtained lower SSA than POP-9, and it had the highest peak at pore diameter of 1.3 nm both in the differential SSA vs. pore diameter and TPV vs. pore diameter curves, but the deionized water had a negative effect on the formation of pores thus POP-11 was poorly porous