The Study Of High Performance PVC Material Micro-Nano Lamination Preparation Device And Property

PVC is the largest output and the most widely used synthetic resin in our country. Because of its extensive sources, excellent comprehensive performance, low price, easy molding and sealing characteristics, it is widely used in packaging materials field. But, on the other hand, because the barrier property of PVC cannot meet the high requirements of some packing materials, and the problem of plasticizer and other additives for its poor thermal stability brings about the problems of environmental protection and potential toxicity, all of these limit the development of PVC material in packaging field. Micro-nano lamination extrusion technology is a new processing method, materials can be divided into hundreds of micro layers using this technology, and the thickness of each layer can reach micron or even nanometer level, the morphological structure of polymer materials can be changed, so as to obtain more excellent performance of functional materials. This paper proposes a new micro-nano lamination device, and single PVC material is extruded using this device, and the gas barrier properties and plasticizer migration performance of the PVC sheets produced by micro-nano lamination extrusion technology have been researched. The main contents are as follows:1. The barrier properties and plasticizer migration performance of polymer materials are introduced, and the methods of improving barrier properties and inhibiting plasticizer migration of polymer materials are summarized. The mechanism of penetration effect is described briefly, and the factors that affect the penetration effect are emphatically introduced. Orientation and degree of orientation are briefly introduced, and the measurement methods of the degree of orientation of polymer materials are summarized. The micro-nano lamination extrusion technology is introduced, and the principle and the progress of micro-nano lamination technology are described. The new idea of using micro nano laminated extrusion device for preparing high performance PVC products has been put forward, and its feasibility is proved in theory.2. A new micro-nano lamination device is proposed, and its structure and principle are introduced. The structure of the micro-nano lamination device is optimized, and a micro-nano lamination extrusion line is established and the preliminary extrusion test is conducted using this line. The extrusion process of the polymer melt in lamination runner is stimulated using POLYPLOW software, which provided a reference for the flow situation of the melt flow in the lamination runner.3. Single PVC materials are extruded using the micro-nano lamination extrusion line, and hard and soft PVC sheets with 1 layer,9 layers and 81 layers are prepared. Through the characterization of orientation degree, mechanical properties and barrier properties of hard PVC sheets, and through the characterization of density, mechanical properties and plasticizer thermal volatilization performance of soft PVC sheets, the effect on orientation degree from lamination device and the effect on performance from its orientation degree are analyzed. The results show that, the special design runners of the micro-nano lamination device has a tensile and shear effect on PVC melt during the extrusion process, the PVC molecular chains arrange more orderly and compactly along the extrusion direction, resulting in improved performance. And in the experimental range, with the increase in the number of stacked device, the effect is more obvious.4. According to the problem that the orientation when plastic melt passed through the self-made laminated device in mold, the simulation of the laminated oriented unit was carried out by using Moldex3D simulation software, fiber distribution of Short fiber reinforced resin matrix composite in laminated oriented unit was studied. The results showed that in extended thinning laminated unit, fiber got a good orientation, the orientation degree of surface fiber was highest; along the direction of extrusion fibers dispersion morphogenesis was controllable, the orientation degree was high; vertical the direction of extrusion fiber was randomly arranged and no orientation effect.