Soluble Organic Microporous Materials Based On Triptycene: Synthesis And Their Capabilities

Organic microporous material,a kind of organic porous materials with pore sizes less than 2 nm,have great potential applications in many fields such as physical separation,heterogeneous catalysis and energy storage.However,most organic microporous materials are insoluble polymer,which limited their further application.How to synthesize soluble microporous materials is still a great challenge for researchers.In this paper,we employed triptycenes as monomers to synthesize soluble microporous polymers or cage because of their highly symmetrical and rigid structure.The main research and results of this work are followed:1)We synthesized fluorine-contained tripticene-based polyimide（FTPI）from the reaction of 2,6-diaminotripticene and 4,4’-（hexafluoroisopropylidene）diphthalic anhydride（6FDA）.The structure of FTPI was also characterized by ¹H NMR,FT-IR,TGA,GPC.Subsequently,Electrospinning was employed to fabricate the nanofibrous membrane from FTPI polymer due to the good soluble.The membrane of FTPI showed a large water contact angle（WCA）（121^o）,high flux and great separation efficiency（beyond 99%）for oil/water mixtures.We believe that the fluorine-contained nanofibrous membranes may be considered as promising candidates for oil/water separation.2)We split two kinds of chiral 2,6-diaminotriptycene（R,R-1,S,S-1）by separating the racemic 2,6-diaminotriptycene,and identified their absolute configurations by X-ray single crystal diffraction.Using R,R-1,S,S-1 as monomer react with 6FDA to synthesize chiral polymers R-FTPI and S-FTPI,respectively,also characterized by NMR,FT-IR,TGA,GPC,CD and optical rotation.Furthermore,we fabricated S-FTPI film by solvent evaporation method and separated three kinds of racemic molecular（rac-1,rac-Binol and rac-Man）,the experimental results indicated that S configuration of racemic molecular could permeate S-FTPI film selectively,the highest enantiomeric excess is 67%.The chiral polymer film,with selective separation of the racemic molecular,expand the microporous materials application in the separation of the chiral membrane.3)Employing triptycene and ethynylene as units,the cage molecule 4-1 was synthesized and characterized by ¹H NMR and X-ray single crystal diffraction.Additionally,we adjusted its porous properties by changing assemble process.The crystalline state will plug pores because of molecule intensive assembly,while the disorder structure of 4-1exhibited high BET surface area(653 m² g^-1)and good CO₂ adsorption capacity（8.3 wt%）.