聚吡咯均苯三酸铜复合材料的制备、表征与分离产物聚吡咯的CO_(2)吸附性能

Synthesis and characterization of polypyrrole@copper pyromellitic and CO_(2) adsorption ability of separated polypyrrole

聚吡咯的合成方法不同,得到的聚吡咯的分子结构和性能都会有明显的差异。因此,以金属有机框架材料均苯三酸铜(Cu-BTC)为主体材料,采用碘氧化法在其三维孔道内实现了吡咯(Py)的自由基氧化聚合,得到了聚吡咯PPy@Cu-BTC复合材料。采用粉末XRD、SEM、FTIR、TG及N_(2)吸脱附等方法对Cu-BTC、Py@Cu-BTC、PPy@Cu-BTC进行表征,证明孔内聚合的成功进行。Cu-BTC在聚合过程中保持了结构的稳定,其形貌也未发生改变。所制备的PPy@Cu-BTC复合材料基于主客体之间的电荷转移和π-π键的相互作用,其电导率为10^(−4) S/cm,相对于块体PPy及Cu-BTC模板至少提高四个数量级,是一种半导体材料。N_(2)吸脱附表明,除去模板后分离得到的PPy具有多孔性,对CO_(2)有着较好地吸收能力,其最大吸收值约为16 cm^(3)/g,相对于块状聚吡咯,其吸收能力翻了一倍。

The molecular structure and performance of polypyrrole is very different due to the difference of its synthesis methods.Utilizing a metal-organic framework(MOF)named copper pyromellitic(Cu-BTC)with threedimensipnal(3D)mesoporous channels as the host material,the radical polymerization of pyrrole(Py)was conducted in the pores by iodine oxidation method to obtain the composite material polypyrrole@Cu-BTC(PPy@Cu-BTC).XRD,SEM,FTIR,TG and N_(2) adsorption-desorption isotherm were used to characterize the prepared Cu-BTC,Py@Cu-BTC and PPy@Cu-BTC,showing the successful synthesis of polymerization in the pores.During the polymerization,the structure and morphology of Cu-BTC keep stable.Based on the charge transfer of host-guest complexation andπ-πinteraction,the PPy@Cu-BTC composite is a semiconductor material and has a conductivity of 10^(−4) S/cm which is at least four orders of magnitude higher than the conductivity of the template Cu-BTC and the asprepared solid polypyrrole.N_(2) adsorption measurement indicated that the as-synthesized PPy separated from PPy@Cu-BTC composite is porous,which has excellent absorption ability of CO_(2) with a maximum absorption value of 16 cm^(3)/g and twice as much as the absorption ability of the as-synthesized solid PPy.