The Nonwovens Institute, North Carolina State University , Raleigh, North Carolina 27606, United States.
Department of Textile Engineering, Chemistry & Science, College of Textiles, North Carolina State University , Raleigh, North Carolina 27695, United States.
Langmuir. 2017 Aug 1;33(30):7452-7458. doi: 10.1021/acs.langmuir.7b01508. Epub 2017 Jul 21.
Here we report a highly conductive polypropylene-graphene nonwoven composite via direct coating of melt blown polypropylene (PP) nonwoven fabrics with graphene oxide (GO) dispersions in N,N-dimethylformamide (DMF), followed by the chemical reduction of GO with hydroiodic acid (HI). GO as an amphiphilic macromolecule can be dispersed in DMF homogeneously at a concentration of 5 mg/mL, which has much lower surface tension (37.5 mN/m) than that of GO in water (72.9 mN/m, at 5 mg/mL). The hydrophobic PP nonwoven has a surface energy of 30.1 mN/m, close to the surface tension of GO in DMF. Therefore, the PP nonwoven can be easily wetted by the GO/DMF dispersion without any pretreatment. Soaking PP nonwoven in a GO/DMF dispersion leads to uniform coatings of GO on PP-fiber surfaces. After chemical reduction of GO to graphene, the resulting PP/graphene nonwoven composite offers an electrical conductivity of 35.6 S m at graphene loading of 5.2 wt %, the highest among the existing conductive PP systems reported, indicating that surface tension of coating baths has significant impact on the coating uniformity and affinity. The conductivity of our PP/graphene nonwoven is also stable against stirring washing test. In addition, here we demonstrate a monolithic supercapacitor derived from the PP-GO nonwoven composite by using a direct laser-patterning process. The resulted sandwich supercapacitor shows a high areal capacitance of 4.18 mF/cm in PVA-HSO gel electrolyte. The resulting highly conductive or capacitive PP/graphene nonwoven carries great promise to be used as electronic textiles.
我们通过将氧化石墨烯 (GO) 分散体直接涂覆在熔融纺制的聚丙烯 (PP) 非织造布上来制备具有高导电性的聚丙烯-石墨烯非织造复合纤维，该分散体是在 N,N-二甲基甲酰胺 (DMF) 中制备的，随后用氢碘酸 (HI) 将 GO 化学还原。GO 作为一种两亲性大分子可以在 5mg/mL 的浓度下均匀分散在 DMF 中，其表面张力 (37.5mN/m) 远低于水中的 GO (72.9mN/m，在 5mg/mL 时)。疏水的 PP 非织造布的表面能为 30.1mN/m，与 DMF 中 GO 的表面张力相近。因此，PP 非织造布可以很容易地被 GO/DMF 分散体润湿，而无需任何预处理。将 PP 非织造布浸泡在 GO/DMF 分散体中会导致 GO 在 PP 纤维表面均匀涂覆。将 GO 化学还原为石墨烯后，所得的 PP/石墨烯非织造布复合材料在 5.2wt%的石墨烯负载下提供了 35.6S/m 的电导率，这是现有导电 PP 体系中最高的，表明涂层浴的表面张力对涂层的均匀性和亲和力有显著影响。我们的 PP/石墨烯非织造布的电导率在搅拌清洗测试中也很稳定。此外，我们还通过直接激光图案化工艺展示了一种由 PP-GO 非织造布复合材料衍生而来的整体超级电容器。所得到的三明治超级电容器在 PVA-HSO 凝胶电解质中表现出 4.18mF/cm 的高面电容。这种具有高导电性或电容性的 PP/石墨烯非织造布有望用作电子纺织品。
