Mechanism And Equipment Research Of Several Polymer Co-Extrusion In Cast Die

With the improvement of people's life quality and the development of medical and health, military project, and other causes, people's demand for high barrier plastic film is increasing day by day. Compared with normal plastic film, plastic films with high barrier perform better in resistance of oxygen and water and have higher comprehensive performance like mechanical and properties.Because of the low level of our technology and equipment, complex forming process of multilayer composite thin film, and producing difficulties, we have been left in the dust by other countries in the in the field of multi-layer high barrier plastic film processing. At present, the multi-layer high barrier films used in our country rely heavily on imports, which result in a great loss of domestic funds.In order to reverse the backward situation in the field of composite thin film, the problems existing in extrusion molding process of multilayer composite flat membrane are studied in this paper. With the flow field simulation of single layer and multi-layer flow channel of the composite thin film forming machine, the effects of flow structure, physical parameters and operating conditions on the melt flow uniformity and stability of the single layer flow channel are studied. The influence of material parameters, working conditions and flow channel structure on the bending and wave properties of the composite interface was studied as well. The specific research contents are as follows:1. Study of the effect of flow structure, physical properties and working conditions in the composite film single head channel on the melt flow uniformity by Using FLUENT software to simulate and analyze the flow of melt under different conditions; the optimal combination scheme of single channel structure, working conditions and physical parameters of; study of the flow pattern of the melt in the single layer flow channel;2. Researches on the plastic melt composite mechanism and the influence factors on thin film composite interface curvature and stability analysis in the composite head channel, using ANSYS-POLYFLOW to simulate the flow of five layer composite melt, analyzing the influence of die structure size factor, production conditions and material factors on flow and composite interface curvature, and obtaining the optimization scheme of multilayer thin film composite head channel;3. Experiments to verify the influence of structural factors, operating conditions and material properties on the bending and the fluctuation of the composite interface in the composite thin film forming process, to obtain the effect degree of various factors on the composite interface.