Study On Carbon Nanotubes In Modification Of Polymer Materials

With the development of the technology in science, the common materials are very difficult to satisfy numerous needs, so the research in composite materials which have the good synthetic function or have the special function becomes an important direction of current material science developing. Being known for the most prospect material of 21 century, the nanomaterial with its superior function and the extensive usage has become the investigative point in science in new material. Because of the obvious quantum effect appeared while lying the nanodimensions, The carbon nanotubes have many strange physical properties. Currently, the research of carbon nanotubes composites is put primarily in two ways. The first, Making use of their good mechanical properties improves the trengthen and tenacity of composite materials. Secondly, making use of their good electromagnetic properties increases the electrical conductivity and the electromagnetic shielding performance and photoelectric emission properties of composite materials.In this thesis, we adopted the different methods to prepare the different carbon nanotube composites, and mainly studied their mechanical properties and electric properties. Moreover, we discussed how the addition of carbon nanotubes effect the structure and properties of the composite materials.We prepared EPDM/CNTs composites with the method of machenical mixture.The effect of CNTs content on the mechanical and electric properties of EPDM Rubber were studied. Moreover, the comparison experiment of EPDM reinforced by HAF with that by CNTs was carried out The results showed that the mechanical properties of rubber stock reinforced by CNTs were better than that of rubber stock made from HAF. The addition of CNTs increased the electric properties and the mechanical properties of the composites. SEM images displayed that CNTs dispersed in the matrix innanometer scale and interface bonding was good.Polystyrene/carbon nanotubes composites were prepared with the method of in situ polymerization. The mechanical properties of the composites were studied as well. Moreover, the relationship of the properties and the microstructure of the composites was investigated. The results showed that the addition of carbon nanotubes made the tensile strength, toughness and the breaking elongation of the materials increase. When the dose of carbon nanotubes was 1.0%, the composites had the best mechanical properties. Scanning electric microscope images displayed that carbon nanotubes dispersed in the matrix in nanometer scale. The more molecular weight of extracted polystyrene than that of pure polystyrene proved that the addition of carbon nanotubes was benefit to the polymerization extent of polystyrene.The coatings of carbon nanotubes onto plastic surface were made of with the methods of the hot pressing and spraying. Moreover, the effect of the methods on antistatic property of plastic surfaces was investigated. The results showed that the coatings of carbon nanotubes on plastic surface will highly decrease insulating capacity of plastic surface.. Comparing with the two methods, spraying method will make carbon nanotubes well dispersed in the plastic surface and the conductive surface of the obtained materials will be evener and more stable.