The Synthesis And Properties Of PE/Graphite/Carbon Fiber Reinforced Composite

Heterogeneous Z-N catalysts were prepared by loading TiCl4 on a mixture of modified graphite and carbon fiber with hydroxyl as effective composite fillers in magnesium chloride.The PE composites were produced via in-situ polymerization. In this paper, the effects of different proportion of carrier on the activity of the catalyst were investigated, and the influence of the content of carbon materials on the mechanical properties, thermal properties and crystallization properties of the polyethylene was studied. The main research results are as follows:1. Heterogeneous Z-N catalysts with high activity were prepared by loading TiCl4 on a mixture of graphite as effective composite fillers in magnesium chloride. The dynamic analysis show that polymerization mechanism of Z-N catalysts has nothing with carbon. For the heterogeneous Z-N catalysts, with the increasing proportion of carbon material, activity of catalyst is declining. When the content of magnesium chloride fell to 0 percent, the catalysts is inactive. Phenomenon show that graphite and carbon fiber do not have the right to load the active component. Under the same formulation, activity of heterogeneous Z-N catalysts with graphite is higher than heterogeneous Z-N catalysts with carbon fiber, and graphite is more conducive to the load of active components. SEM show that graphite and carbon fiber has been successfully added to the polyethylene matrix. In the process of growth of polyethylene molecular chain, polyethylene began to copy the morphology of graphite and carbon fiber, then wrapped in them. XRD also proved that graphite and carbon fiber has been added to the polyethylene matrix.2. Graphite and carbon fiber have a great influence on the performance of PE, the activity of catalyst containing graphite is higher, but the mechanical properties of PE containing carbon fiber is better. The tensile strength of PE containing graphite has increased by 30% from pure PE to 34.58MPa; the bending strength of PE containing graphite has increased by 9.3% from pure PE to 24.6MPa, the impact strength of PE containing graphite has increased by 20.6% from pure PE to 111KJ/m2. The tensile strength of PE containing carbon fiber has increased by 36.2% from pure PE to 36.1MPa; the bending strength of PE containing carbon fiber has increased by 16.4% from pure PE to 26.2MPa. the impact strength containing carbon fiber has increased by 41.3% from pure PE to 130KJ/m2. And the PE containing graphite and carbon fiber has a better effect, the tensile strength increased by 45.2% from pure PE to 38.5MPa. In fact, with the increasing content of carbon material, mechanical properties first rises then falls.3. The thermal properties and crystallization behaviors were studied by means of DSC and TG. TGA show that the temperature of maximum speed on loss in weight of PE containing graphite has increased by 19.3 ? from pure PE to 449.3 ?; the temperature of maximum speed on loss in weight of PE containing carbon fiber has increased by 6.6 ? from pure PE to 436.6 ?; the temperature of maximum speed on loss in weight of PE containing graphite and carbon fiber has increased by 18.5 ? from pure PE to 448.5 ?. DSC show that the melt temperature of PE have a slight rise with the adding of carbon material. But with the increasing content of carbon materials, melting point is declining, so did the crystallinity.