聚丙烯腈共价接枝石墨烯的制备与表征

Fabrication and characterization of polyacrylonitrile covalently grafted graphene

针对石墨烯及石墨烯/聚合物纳米材料由于范德华力和π-π相互作用引起的片层堆积问题,采用自由基聚合引发剂引发丙烯腈(AN)与氧化石墨烯(GO)的聚合反应,制备聚丙烯腈接枝石墨烯(PAN-g-GO),并采用SEM、TEM、XRD、XPS、FT-IR和TG等测试方法对PAN-g-GO的结构进行表征。结果表明:PAN分子链被成功地共价接枝到了GO纳米片层表面;通过提高单体和引发剂的比例,不仅可以使石墨烯纳米片的厚度变大,也可以显著提高PAN的接枝率和相对分子质量;当单体和引发剂的摩尔配比为2000∶1时PAN-g-GO的接枝率由1000∶1时的83.07%提高到884.33%,相对分子质量由1.9×10^(4)提高到17.6×10^(4),且分散性良好,在DMF中静置60 d后颜色均匀,未发现类似GO的团聚堆积情况。

Aiming at the problem of lamellar stacking caused by the Van Der Waals force andπ-πinteraction of graphene and graphene/polymer nano materials,polyacrylonitrile(PAN)was grafted onto graphene oxide(GO)using a free radical polymerization(FRP)initiator to fabricate PAN-g-GO.SEM,TEM,XRD,XPS,FT-IR and TG were used to characterize the structure of PAN-g-GO.The results showed that,the PAN molecular chains could be successfully covalently grafted onto the GO nanosheet surface by FRP technique.By increasing the ratio of monomer to initiator,not only the thickness of graphene nanosheets could be increased,but also the grafting rate and relative molecular weight of the grafted PAN could be increased.When the molar ratio of monomer to initiator was 2000∶1,the grafting rate of PAN-g-GO increased from 83.07%at 1000∶1 to 884.33%,and its relative molecular weight increased from 1.9×10^(4)to 17.6×10^(4).PAN-g-GO with the ratio of monomer to initiator of 2000∶1 has good dispersion and its color was uniform after standing in DMF for 60 days,and no agglomeration and accumulation similar to GO was found.