Tuning Of Specific Surface Area And CO₂ Capture Performance In Hyper-Cross-Linked Microporous Polymers Containing Tetrazine Linker

As an important subdiscipline of organic microporous polymers,hyper-cross-linked polymers?HCPs?have rigid networks,high specific surface areas?SSA?,and high chemical/thermal stabilities.Due to these virtues,HCPs offer great potential applications in gas adsorption and separation,chromatography,catalysis,and drug delivery.At present,however,how to fine-tune the SSA of HCPs is still a challenge.Based on this,five building blocks with different reactive motifs connecting by the same tetrazinyl linker were firstly synthesized in this thesis,whose structures were similar,i.e.,“reactive motif-tetrazinyl linker-reactive motif”.Then the corresponding hyper-cross-linked networks were synthesized by the Friedel–Crafts reaction using both Lewis acid?Fe Cl₃ and Al Cl₃?and Br?nsted acid?CF₃SO₃H?as the catalysts.The tuning in SSA and the CO₂ capture performance of such HCPs were also investigated.The main research results are as follows:?1?Tuning of SSA and CO₂ capture performance in hyper-cross-linked poly?N-heterocycles?with tetrazinyl linker.In this chapter,three building blocks?TPy,TIn and TCz?with pyrrolyl?Py?,indolyl?In?,and carbazolyl?Cz?groups connecting by the same tetrazinyl linker were firstly synthesized.The corresponding hyper-cross-linked networks?HCTPys,HCTIns,and HCTCzs?were then synthesized by the Friedel–Crafts reaction using both Lewis acid?Fe Cl₃ and Al Cl₃?and protonic acid?CF₃SO₃H?as the catalysts.It has been demonstrated that the SSA of the resultant HCTPys,HCTIns,and HCTCzs can be finely tuned by the size of reactive groups,in which the SSA increases with increasing the size of reactive groups and is in the order of HCTCzs>HCTIns>HCTPys,regardless of the catalysts.Specifically,the HCTCz prepared by the Al Cl₃-catalyzed Friedel–Crafts reaction displayed a high CO₂ uptake capacity(4.90 mmol g^-1)as well as a high isosteric heat of CO₂ uptake(31.60-29.86k J mol^-1)and a good CO₂/N₂ selectivity?31.2?at 273 K,showing a great potential for CO₂ capture.?2?Tuning of SSA and CO₂ capture performance in hyper-cross-linked poly-?substituted?indole with tetrazinyl linker.In this chapter,three building blocks?TIn,T3Ph In and T2,3Ph In?with indolyl?In?,3-phenylindolyl?3Ph In?and 2,3-phenyl-indolyl?2,3Ph In?groups connecting by the tetrazinyl linker were firstly synthesized.The corresponding hyper-cross-linked networks?HCTIns,HCT3Ph Ins and HCT2,3Ph Ins?were then synthesized by the Friedel–Crafts reaction using both Lewis acid?Fe Cl₃ and Al Cl₃?and protonic acid?CF₃SO₃H?as the catalysts.It has been found that the SSA of the resultant HCTIns,HCT3Ph Ins and HCT2,3Ph Ins can be finely tuned by the number of phenyl substituents,in which SSA increases with increasing the number of phenyl substituents and is in the order of HCT2,3Ph Ins>HCT3Ph Ins>HCTIns,regardless of the catalysts.Specifically,the HCT2,3Ph In prepared by Al Cl₃-catalyzed Friedel–Crafts reaction showed a high CO₂ uptake capacity(4.50 mmol g^-1)together with a high isosteric heat of CO₂ uptake(30.38-28.73 k J mol^-1)and a good CO₂/N₂ selectivity?27.9?at 273 K,showing a great potential for CO₂ capture.