Preparation of Microporous Polymers Consisting of Tetraphenylethene and Alkyne Units

We prepared tetraphenylethene (TPE)-based microporous polymers TPE-DB, TPE-TB, and TPE-AD by Sonogashira-Hagihara cross-coupling reaction of tetrakis(4-iodophenyl)ethene with 1,4-diethynylbenzene (DB), 1,3,5-triethynylbenzene (TB), and tetrakis(4-ethynylphenyl)adamantane (AD), respectively. Polymers TPE-DB/TB(1:2) and TPE-DB/TB(3:2) having two different ethynyl units were also obtained by using mixtures of 1,4-diethynylbenzene and 1,3,5-triethynylbenzene in molar ratios of 1: 3 and 1: 1, respectively, for the coupling reaction. The polymers were isolated as aggregated particles. The Brunauer-Emmett-Teller (BET) surface areas of the polymers were dependent on the structures of the ethynylbenzenes. Among the polymers with one type of ethynyl unit, TPETB showed the highest BET surface area of 1,231 m 2 /g, followed by TPE-DB (404 m 2 /g) and TPE-AD (615 m 2 /g). TPE-DB/TB(3:2) with two different ethynyl units exhibited a considerably enhanced BET surface area of 1,835 m 2 /g compared with TPE-DB and TPE-TB, suggesting the significant change in the polymer microstructure. The polymers except TPE-DB showed CO 2 and H 2 uptakes over 40 and 100 cm 3 /g, respectively.