Study On The Interfacial Interaction Of PVC / Graphene - Carbon Nanotube Composites By Zinc Oxide

As we all know, two new nano-carbon materials: multi-walled carbon nanotubes(MWCNTs) and graphene(Graphene), because of its unique structure and excellent performance, become the focus of the current domestic and foreign research. For example, Graphene which forms of carbon atoms and only the single-atom thick because of its superior thermal, electrical, mechanical and optical properties, and thus become the focus of physics, chemistry, biology, materials, electronics, energy and information technology sectors. Graphene and MWCNTs are widely used in polyvinyl chloride(PVC) composites, because of the introduction of the polymer composites impart excellent mechanical, electrical, thermal and optical properties. However, there are some problems to be solved in the polymer. Graphene and MWCNTs easy restack and have the weak interface interaction between the polymer and fillers. Because the two key factors that the dispersion state in the matrix and the filler- matrix interface interaction determine the final properties of PVC composite material. In this paper we focuse on two nano carbon materials dispersed state and interfacial interactions in the matrix.To solve the above problems, the present paper set graphene oxide(GO) and acid-treatmented MWCNTs as a starting point, and by surface modify of MWCNTs and Graphene to increase its polarity, in order to improve their dispersion and interface interactions between PVC matrix. The main contents include the following aspects:(1) GO, originating form graphite flakes, was prepared by Hummers method, under hydrothermal conditions, and through the "one-pot" method successfully prepared reduced graphene oxide- zinc oxide(rGO-Zn O) hybrids. To make this comparison, we use simple physical blend method prepared the same ratio of graphene nanosheets /zinc oxide mixture(GNPs/ZnO). By using X-ray diffraction(XRD), photoluminescence(PL), Atomic force microscopy(AFM), Electrochemical measurement, Scanning electron microscopy(SEM) and transmission electron microscopy(TEM) test analysis rGO-ZnO and GNPs/ZnO structure and properties. The results showed that, in rGO-Zn O hybrids, ZnO not only exists between r GO surface layers, and has a strong interaction between the two, but also makes rGO a certain polarity, it can be well dispersed in tetrahydrofuran(THF), whereby the polymer matrix has good compatibility.(2) PVC/rGO-ZnO and PVC/GNPs/ZnO composites were prepared by solution blending, in order to study their loading effects, each filler mass fraction of 5 wt%, 10 wt%, 15 wt% and 20 wt% composites were filled. By using Differential scanning calorimetry(DSC), the Contact angle measurement, Scanning electron microscopy(SEM) and universal tensile test to test the mechanical properties and structure analysis of PVC / rGO-ZnO and PVC/GNPs/ZnO composites. The results showed that with the added 15 wt% rGO-ZnO hybrids, compared with pure PVC, tensile strength and Young’s modulus were improved by 35% and 41%, respectively. The enhancement of the mechanical properties mainly due to the filler – matrix had a strong interaction, which is by the action of ZnO "bridge" to achieve, namely p-π overlapping effects and electrostatic attraction between ZnO and rGO, as well as PVC the electrostatic attraction/hydrogen bonding between the chain. High interfacial interaction also helps nanoparticles uniformly dispersed in PVC matrix, and increases the glass transition temperature(Tg).(3) nitric acid treated MWCNTs which as a starting point and GO as a surfactant, under hydrothermal conditions, with the "one-pot" preparation of a multi-walled carbon nanotubes- reduced graphene oxide- zinc oxide of the 3D mixture(MWCNTs-rGO-Zn O), in order to make its comparison, also prepared the same proportions of multi-walled carbon nanotubes- reducing graphene oxide mixture(MWCNTs-rGO) and reduced graphene oxide- zinc oxide mixture(rGO-Zn O). By using X-ray diffraction(XRD), scanning electron microscopy(SEM), Thermal gravimetric analysis(TGA) and Transmission electron microscopy(TEM) analysis to test their structure and performance. The results showed that MWCNTs-rGO-ZnO hybrids had a strong interaction between the three, due to the presence of ZnO, it has a good compatibility with an organic solvent, polarity has also been enhanced to better with the polymer matrix phase capacitive(4) PVC/MWCNTs-rGO-ZnO, PVC/rGO-Zn O and PVC/MWCNTs-rGO composites were prepared by solution blending, in order to study their loading effects, each filler mass fraction of 0.1 wt%, 0.5 wt%, 1 wt%, 2 wt%, 3 wt% and 5 wt% of the composite were filled with. By using Thermal gravimetric analysis(TGA), Differential scanning calorimetry(DSC), Raman(Raman), Scanning electron microscopy(SEM) and universal tensile test to test the mechanical analysis of their structure and properties. The results showed that, between PVC and MWCNTs-rGO-ZnO, there forms a strong interfacial interaction, promote the formation of good dispersion, the largest increase significantly improve the performance of composite materials, such as tensile strength of 30%, the biggest increase in Young’s modulus of 60%, electrical conductivity and thermal stability have also been improved significantly.