STRUCTURALLY STABLE COMPOSITE STRUCTURE CHROMOGENIC MATERIAL AND PREPARATION METHOD THEREFOR

20230142236 · 2023-05-11

    Inventors

    Cpc classification

    International classification

    Abstract

    A structurally stable composite structural chromogenic material and a preparation method thereof are provided. The structurally stable composite structural chromogenic material is formed by stacking a transparent thermoplastic polymer and a structural chromogenic material layer by layer and then thermally bonding the peripheral edges of the polymer into a whole, and the upper surface layer and the lower surface layer of the material are both thermoplastic polymers. The molded composite structure has relatively obvious structural color and good mechanical strength.

    Claims

    1. A structurally stable composite structural chromogenic material, which is formed by stacking transparent thermoplastic polymer and structural chromogenic material layer by layer and then thermally bonding peripheral edges of the polymers into a whole, wherein an upper surface layer and an lower surface layer of the composite material are both thermoplastic polymers.

    2. The material according to claim 1, wherein a total number of layers of the composite structural chromogenic material is 3 to 15.

    3. The material according to claim 1, wherein the structural chromogenic material is a film built of micro-nano spheres by ordered or disordered stacking; wherein the micro-nano spheres are inorganic microspheres or heat-resistant organic microspheres, having a diameter of 10 to 1000 nm, which are solid or hollow; wherein the heat-resistant organic microsphere is organic microsphere with vitrification temperature higher than that of the thermoplastic polymer.

    4. The material according to claim 3, wherein the inorganic microsphere is silicon dioxide microsphere, titanium dioxide microsphere, zinc oxide microsphere, alumina microsphere, zirconium dioxide microsphere, or vanadium pentoxide microsphere; and the heat-resistant organic microsphere is cross-linked polymer microsphere or sulfur-containing resin microsphere.

    5. The material according to claim 1, wherein the thermoplastic polymer is one of polyethylene, polypropylene, polyvinyl chloride, polystyrene, polyformaldehyde, polycarbonate, polyamide, acrylic plastic, other polyolefins and copolymers thereof, polysulfone, polyphenyl ether, polyurethane, polytetrafluoroethylene, and polyethylene terephthalate.

    6. A method for preparing the structurally stable composite structural chromogenic material according to claim 1, comprising the following processing steps of: orderly or disorderly assembling an emulsion of micro-nano sphere with a solid content of 5% to 30% on a transparent thermoplastic polymer layer to build a structural color layer; covering another transparent thermoplastic polymer layer on the obtained thermoplastic polymer layer coated with the structural color layer, and hot-pressing to bond the peripheral edges of the two thermoplastic polymer layers to form a whole to obtain a structurally stable composite structural chromogenic material unit; and hot-pressing to bond the peripheral edges of the thermoplastic polymer layers of the obtained composite structural chromogenic material units and the two contacting polymer layers fit and bonding them into a whole by hot-pressing.

    7. A method for preparing the structurally stable composite structural chromogenic material according to claim 1, comprising the following processing steps of: orderly or disorderly assembling an emulsion of micro-nano sphere with a solid content of 5% to 30% on a transparent thermoplastic polymer layer to build a structural color layer; covering another transparent thermoplastic polymer layer on the obtained thermoplastic polymer layer coated with the structural color layer, repeating the above operations until obtaining a target number of layers, and hot-pressing to bond all the peripheral edges of the thermoplastic polymer layers to form a whole; or hot-pressing in steps until obtaining the target number of layers.

    8. The method according to claim 6, wherein in the preparing process of the structural color layer, the micro-nano spheres are co-assembled with an adhesive, wherein the adhesive is at least one of dopamine and derivatives thereof, Arabic gum, natural gum, natural rubber, polyurethanes, polyureas, polyacrylates, phenolic resins, epoxy resins, and polyvinyl alcohols, and a mass fraction of the adhesive in the emulsion of micro-nano spheres ranges from 0% to 20%.

    9. The method according to claim 6, wherein methods of orderly assembling micro-nano spheres on the thermoplastic polymer layer comprises heating assembly method, deposition, blade coating, and spin casting; and methods of disorderly assembling micro-nano spheres on the thermoplastic polymer layer comprises drop casting, spray coating, and printing.

    10. The method according to claim 6, wherein an equipment bonding two thermoplastic polymer layers into a whole is a hot-pressing equipment, wherein a temperature of the hot-pressing ranges from 80 to 250° C. and pressure ranges from 4 to 16 kN.

    Description

    DETAILED DESCRIPTION OF DRAWINGS

    [0035] FIGS. 1 (a) to (c) are the photographs of the structurally stable composite structural chromogenic material obtained in Embodiment 1.

    [0036] FIG. 2 is a cross-sectional scanning electron microscopy photograph of the structurally stable composite structural chromogenic material c obtained in Embodiment 1.

    [0037] FIG. 3 is a peel curve of PVC test sample prepared under the hot-pressing condition in Embodiment 1 (the width of the spline is 2.5 cm, and the overlap length of the hot-pressing is 5 mm), indicating that the peel load is 273 N.

    [0038] FIG. 4 is a comparison diagram before and after the friction test of the structurally stable composite structural chromogenic material c obtained in Embodiment 1. The test condition is of horizontally dragging the material with a load of 1 kg on 100 mesh sandpaper for 10 cm at a speed of 5 cm/s for reciprocating 15 times.

    [0039] FIGS. 5 (a) and (b) are photographs of normal and warped mobile phone shells of the structurally stable composite structural chromogenic material obtained in Embodiment 2.

    [0040] FIG. 6 is a photograph of the structurally stable composite structural chromogenic material obtained in Embodiment 3.

    [0041] FIG. 7 is a schematic diagram of the structurally stable composite structural chromogenic material of the present disclosure.

    DETAILED DESCRIPTION OF PREFERRED EMBODIMENTS

    [0042] The following non-limiting embodiments may enable those ordinary skilled in the art to understand the present disclosure more comprehensively, however, they do not intend to limit the present disclosure in any way.

    [0043] The test methods in the following embodiments are conventional methods unless otherwise specified. The reagents and materials can be commercially obtained unless otherwise specified.

    Embodiment 1

    [0044] 1. Under the cover of a hollow-out mold, using spraying method, the emulsions of bisphenol formaldehyde resin microspheres with diameters of 283 nm, 239 nm and 197 nm respectively, having a solid content of 10%, were sprayed on the PVC film to disorderly assemble and prepare amorphous photonic structure patterns with three colors.

    [0045] 2. The hot-pressing equipment was preheated to 120° C. Another PVC film layer was covered on the PVC film having amorphous photonic structure patterns and the two PVC film layers were bonded into a whole by hot-pressing with a pressure of 8 kN, to obtain a structurally stable composite structural chromogenic material. The structural stability was verified by peel test. The peel load of the PVC test sample prepared under this hot-pressing condition was 273 N. Further, through the friction test, the composite structural chromogenic material with a load of 1 kg was horizontally dragged on 100 mesh sandpaper for 10 cm at a speed of 5 cm/s for reciprocating 15 times. The shape and color of the patterns were maintained.

    Embodiment 2

    [0046] 1. The emulsions of bisphenol formaldehyde resin microspheres with diameters of 283 nm, 239 nm and 197 nm respectively, having a solid content of 10%, were mixed with carbon black aqueous solution having a solid content of 0.01 g/mL at the mass ratio of 20:1 to prepare mixed emulsions. Under the cover of a hollow-out mold, using spraying method, the three kinds of mixed emulsions of bisphenol formaldehyde resin microspheres were respectively sprayed on the TPU film to disorderly assemble and prepare amorphous photonic structure patterns.

    [0047] 2. The hot-pressing equipment was preheated to 120° C. A TPU mobile phone shell was covered on the TPU film having amorphous photonic structure patterns. The two TPU film layers were bonded into a whole by hot-pressing with a pressure of 8 kN, to obtain a mobile phone shell of structurally stable composite structural chromogenic material.

    Embodiment 3

    [0048] 1. Using heating assembly method, a PVC film was placed on the heating plate at a temperature of 60° C., and the emulsion of bisphenol formaldehyde resin microspheres having a solid content of 10% and a diameter of 283 nm was orderly assembled on the PVC film to prepare the photonic crystal.

    [0049] 2. The hot-pressing equipment was preheated to 120° C. Another PVC film layer was covered on the PVC film having the photonic crystal layer. The two PVC film layers were bonded into a whole through hot-pressing with a pressure of 8 kN, to obtain a structurally stable composite structural chromogenic material.

    Embodiment 4

    [0050] 1. Under the cover of a hollow-out mold, using spraying method, the emulsion of silicon dioxide microspheres having a solid content of 10% was sprayed on the PVC film to disorderly assemble and prepare amorphous photonic structure patterns.

    [0051] 2. The hot-pressing equipment was preheated to 120° C. Another PVC film layer was covered on the PVC film having amorphous photonic structure patterns. The two PVC film layers were bonded into a whole through hot-pressing with a pressure of 8 kN, to obtain a structurally stable composite structural chromogenic material.

    Embodiment 5

    [0052] 1. Under the cover of a hollow-out mold, using drop-casting method, the emulsion of polysulfide resin microspheres having a solid content of 10% was disorderly assembled on the TPU film to prepare amorphous photonic structure patterns.

    [0053] 2. The hot-pressing equipment was preheated to 110° C. Another TPU film layer was covered on the TPU film having amorphous photonic structure patterns. The two TPU film layers were bonded into a whole through hot-pressing with a pressure of 8 kN, to obtain a structurally stable composite structural chromogenic material.

    Embodiment 6

    [0054] 1. Using blade coating method, the emulsion of titanium dioxide microspheres having a solid content of 10% was orderly assembled on the PVC film to prepare photonic crystal.

    [0055] 2. The hot-pressing equipment was preheated to 120° C. Another PVC film layer was covered on the PVC film having the photonic crystal layer. The two PVC film layers were bonded into a whole through hot-pressing with a pressure of 8 kN, to obtain a structurally stable composite structural chromogenic material.

    Embodiment 7

    [0056] 1. Using spin casting method, the emulsion of zinc oxide microspheres having a solid content of 10% was orderly assembled on the TPU film to prepare photonic crystal.

    [0057] 2. The hot-pressing equipment was preheated to 120° C. Another TPU film layer was covered on the TPU film having the photonic crystal layer. The two PVC film layers were bonded into a whole through hot-pressing with a pressure of 8 kN, to obtain a structurally stable composite structural chromogenic material.

    Embodiment 8

    [0058] 1. Using spray coating method, the emulsion of bisphenol formaldehyde resin microspheres having a solid content of 10% and a diameter of 239 nm was sprayed on a PVC film to disorderly assemble and prepare amorphous photonic structure. Another PVC film layer was covered on the PVC film having amorphous photonic structure.

    [0059] 2. The above operations were repeated to form a composite structure with five layers, in which the structural chromogenic materials are respectively between the continuous polymer layers on both sides.

    [0060] 3. The hot-pressing equipment was preheated to 120° C. The peripheral edges of all PVC layers were bonded into a whole through hot-pressing with the pressure of 8 kN, to obtain a structurally stable composite structural chromogenic material.

    Embodiment 9

    [0061] 1. Using printing method, the emulsion of titanium dioxide microspheres having a solid content of 10% and a diameter of 230 nm was printed on the PVC film to disorderly assemble and prepare the structural color patterns.

    [0062] 2. The hot-pressing equipment was preheated to 120° C. Another PVC film layer was covered on the PVC film having structural color patterns. The two PVC film layers were made fit and bonded into a whole through hot-pressing, with the pressure of 8 kN, so as to obtain a structurally stable composite structural chromogenic material.

    Embodiment 10

    [0063] 1. Under the cover of a hollow-out mold, using spraying method, the emulsion of bisphenol formaldehyde resin microspheres having a solid content of 10%, wherein the mass fraction of polyacrylate adhesive in the emulsion is 1%, was sprayed on the PVC film to disorderly assemble and prepare amorphous photonic structure patterns.

    [0064] 2. The hot-pressing equipment was preheated to 120° C. Another PVC film layer was covered on the PVC film having amorphous photonic structure patterns. The two PVC film layers were bonded into a whole through hot-pressing with a pressure of 8 kN, to obtain a structurally stable composite structural chromogenic material.

    [0065] The above embodiments are only used to help better understand the core idea and technical method of the present disclosure, but cannot limit the protection scope of the present disclosure. It should be noted that those ordinary skilled in the art may make various improvements and variations to the present disclosure on the basis of the principles of the present disclosure shall fall within the protection scope of the present disclosure. Any equivalent replacement or modification made according to the spirit and essence of the present disclosure shall fall within the protection scope of the present disclosure.