Preparation And Performances Of Graphene/PVC Composites

PVC resin is the world’s first industrialized production of plastic varieties,it has many excellent properties,such as high mechanical strength, chemical resistance, abrasion resistance and excellent electrical insulation,these make it widely used in construction, chemical, coal, electronics, automotive and other industries.But PVC belongs to hard and brittle materials without plasticizers,it prones to develop micro-cracks under the friction stress,thus limiting the application of pvc on the areas demanding higher tribological properties.In addition, flexible PVC is easy to gather electrostatic witch will cause damages for electronic products.Therefore, to enhance and improve wear resistance and antistatic properties of PVC has become an important function of its modified development.Graphene is a new type of nano-carbon material with superior electrical conductivity,carrier mobility,mechanical strength and other characteristics,as the research on graphene has been widely implemented, more and more interests are focused on the applications of graphene in industrial production applications.The preparation of graphene functional composites provides new possibilities for both fundamental researches and practical applications of nano-materials, playing a role of bridges in linking the novel nanomaterials and the conventional macroscopic materials (for example, polymers) together.The purpose of this paper is the preparation of high-performance graphene/PVC composite materials,to take full advantage of graphene in mechanical and electrical aspects of performance,to significantly improve the wear resistance and conductive properties of PVC.First of all, prepared rigid graphene/PVC composite materials by melt blending,their fracture surfaces at a low temperatures are characterized by SEM,also their micro-hardness are tested,and the friction and wear properties of the composites are investigated under the dry friction condition,to analyze the influence of Graphene on friction and wear rate of the composites. The results show that, after filled with gaphene,the composite materials’brittle fracture converted into ductile fracture,and when the content of graphene is up to 1.2 wt%,the micro-hardness of the composites are lower than pure PVC(13.14Hv),the friction coefficient is lower than pure PVC and the wear rate decreased almost 56%. The friction wear property of the Graphene/PVC composites could be enhanced,mainly due to the high surface area and soft curl property of graphene to better improve the flexibility of rigid PVC,to increase the toughness of the composites.Therefore,the composites prone to occur elastoplastic deformation during the dry sliding friction,effectively avoid the the occurrence of brittle fracture and micro crack propagation,thus significantly improve the wear resistance of the composites.In addition, the self-lubricating of graphene fragments also play a certain role in improving the wear resistance of the composites.Flexible Graphene/PVC antistatic composites with different graphene conent preparaed by double roller mixing method, and study the electrical and mechanical properties of the composites.Found that with the increasing of graphene conent, the surface resistivity of the composites show a decreasing trend.When the content of graphene is up to 4.5 wt%, the surface resistance is 5.7×105Ω/□and reduce 7 orders of magnitude than pure PVC,and its Young’s modulus increases 185% over the pure PVC. Furthermore, the thermal analysis showed that the thermal stability of the composites all have a certain degree of reduction. At the same time.using a new solution method to prepare powders and make them into flexible Graphene/PVC antistatic composites with different graphene conent by hot briquetting. Then explores the structure of conductive network and the electrical properties of the composite materials. The results show that, the powders prepared in this way can make graphene uniformly dispersed in the PVC,in addition, graphene uniformly coats on the surfaces of PVC particles, these two points lay the foundation for building a conductive network.With the increasing of graphene conent,the surface resistivity of the composites show a decreasing trend.When the content of graphene is up to 1.8 wt%, the surface resistance is 3.5×106Ω/□.The improvement of conductivity of the graphene/ PVC composites,mainly due to graphene has excellent conductivity, and as conductive particles overlap each other to form conductive network in the composite.Based on the above studies, show that adding graphene can significantly improve the friction wear property and conductivity of Graphene/PVC composites. This is mainly due to the nano-sheet structure and excellent electrical conductivity of graphene, good compatibility between graphene and polymer, as so as excellent lubricating property of graphene.These Graphene/PVC composites with high wear resistance and high anti-static could be widely used in these areas,such as decks of warships,runways of carrier-based aircraft, antistatic belts, ventilation ducts,and so on.