Hot Embossing Of Optical Functional Polymer Films With Triangular Pyramid Texture

Triangular pyramid texture is an ideal structure for the preparation of optical functional textured polymer films because of its excellent optical properties and large specific surface area.In composite solar cells,the triangular cone texture can improve the photoelectric conversion efficiency of crystalline silicon solar cells by enhancing the light absorption on the solar cell surface.In this thesis,the hot-embossing method of P2P(plane-to-plane)is studied to find out the rule of the influence of the process parameters on the hot-embossing precision,and to optimize the best process parameters to ensure the accuracy and stability of the preparation of the triangular pyramid functional textured polymer film.This article mainly launches the research from the following several aspects:(1)Through the research on the basic theory of the rheology of polymer logistics and the testing of the properties of PVC(polyvinyl chloride)materials,the constitutive model of the polymer is established,and the finite element software Deform is used to simulate the hotembossing process and observe the morphological changes of the PVC polymer in the hotembossing process.In the process of imprinting,the polymer contacts with the side wall of the cavity first and produces the phenomenon of bimodal filling.In this process,the air in the cavity can be directly sealed in the top of the triangular pyramid by continuous wall-climbing fluid.(2)Through experiments to explore the influence of hot-embossing process parameters on the polymer forming process,a simple and high-precision hot-embossing printing equipment is obtained by designing and refitting the tensile testing machine,and the PVC film is selected as the substrate material for processing the triangular pyramid array texture,and the triangular pyramid optical functional texture polymer film with good anti-reflection performance is obtained.Through orthogonal experiments,the effects of imprint temperature,imprint time and imprint pressure on the copying accuracy of triangular cone texture were studied.Through single factor experiment,the process parameters of hot embossing triangular pyramid array polymer film were optimized.The best process parameters were: stamping temperature 170?,holding time 300 S,stamping pressure 2KN.(3)Prepare composite structure battery,and compare the performance of the crystalline silicon solar cell with that of the optical functional texture film before and after the composite by testing the performance of the triangular pyramid optical functional texture film.The results show that the photoelectric conversion efficiency of crystalline silicon solar cells can be effectively improved by optical functional textured films.The weighted reflectance of the composite cell surface is 7.51%,which is 3.85% lower than that of the crystalline silicon solar cell surface.By testing the EQE quantum efficiency and J-V curves,the photoelectric conversion efficiency of the composite structure cell reaches 12.96%,which is 1.03% higher than that of the crystalline silicon cell.At the same time,compared with the surface of textured crystalline silicon,the surface hydrophobic property of the composite solar cell is good,and the surface water contact angle of the composite cell is increased from 46° to 115°,which provides a theoretical basis for the practical research and application of the composite solar cell.