Boldt Regine, Leuteritz Andreas, Schob Daniela, Ziegenhorn Matthias, Wagenknecht Udo
Leibniz Institute of Polymer Research Dresden (IPF), Hohe Strasse 6, 01069 Dresden, Germany.
Faculty Mechanical Engineering, Electrical and Energy Systems, Institute of Mechanical Engineering and Management, Brandenburg University of Technology Cottbus-Senftenberg, Universitaetsplatz 1, 01968 Senftenberg, Germany.
Polymers (Basel). 2020 Mar 17;12(3):669. doi: 10.3390/polym12030669.
It is generally known that significant improvements in the properties of nanocomposites can be achieved with graphene types currently commercially available. However, so far this is only possible on a laboratory scale. Thus, the aim of this study was to transfer results from laboratory scale experiments to industrial processes. Therefore, nanocomposites based on polyamide (PA) and graphene nanoplatelets (GnP) were prepared in order to produce membranes with improved gas barrier properties, which are characterized by reduced permeation rates of helium. First, nanocomposites were prepared with different amounts of commercial availably graphene nanoplatelets using a semi-industrial-scale compounder. Subsequently, films were produced by compression molding at different temperatures, as well as by flat film extrusion. The extruded films were annealed at different temperatures and durations. In order to investigate the effect of thermal treatment on barrier properties in correlation to thermal, structural, and morphological properties, the films were characterized by differential scanning calorimetry (DSC), wide angle X-ray scattering (WAXS), optical microscopy (OM), transmission electron microscopy (TEM), melt rheology measurements, and permeation measurements. In addition to structural characterization, mechanical properties were investigated. The results demonstrate that the permeation rate is strongly influenced by the processing conditions and the filler content. If the filler content is increased, the permeation rate is reduced. The annealing process can further enhance this effect.
众所周知，使用目前市售的石墨烯类型可以实现纳米复合材料性能的显著改善。然而，到目前为止，这仅在实验室规模上是可行的。因此，本研究的目的是将实验室规模实验的结果转化为工业生产过程。因此，制备了基于聚酰胺（PA）和石墨烯纳米片（GnP）的纳米复合材料，以生产具有改善的气体阻隔性能的膜，其特征在于氦气的渗透率降低。首先，使用半工业规模的混合机，用不同量的市售石墨烯纳米片制备纳米复合材料。随后，通过在不同温度下的压缩成型以及通过平膜挤出生产薄膜。将挤出的薄膜在不同温度和持续时间下进行退火。为了研究热处理对与热、结构和形态性能相关的阻隔性能的影响，通过差示扫描量热法（DSC）、广角X射线散射（WAXS）、光学显微镜（OM）、透射电子显微镜（TEM）、熔体流变学测量和渗透测量对薄膜进行表征。除了结构表征外，还研究了机械性能。结果表明，渗透率受加工条件和填料含量的强烈影响。如果填料含量增加，渗透率会降低。退火过程可以进一步增强这种效果。
