Search

CN-122011591-A - Preparation of bionic anchoring polypropylene material for improving adhesive force of water transfer coating for automobile

CN122011591ACN 122011591 ACN122011591 ACN 122011591ACN-122011591-A

Abstract

The invention relates to the technical field of high polymer materials, and discloses a preparation method of a bionic anchoring polypropylene material for improving the adhesive force of a water transfer coating, which comprises a polypropylene matrix, a bionic polar anchoring component containing catechol functional groups and a polypropylene block, and an interface migration auxiliary component with surface tension lower than that of the matrix, wherein the surface tension gradient among the components is utilized, the bionic polar anchoring component is driven to enrich the surface of the material in the molding cooling stage and form a concentration enrichment layer, and catechol functional groups are fixed through the co-crystallization between the polypropylene block and the matrix.

Inventors

  • MO HONGYUAN
  • MO XIU
  • ZHU HONGLIN
  • QIU YUQIN
  • XU WEIJIE

Assignees

  • 郴州科远达汽车精工部品有限公司

Dates

Publication Date
20260512
Application Date
20260326

Claims (10)

  1. 1. The preparation of the bionic anchoring polypropylene material for the automobile for improving the adhesive force of the water transfer printing coating is characterized by comprising the following components in percentage by mass based on 100% of the total weight of the bionic anchoring polypropylene material: a polypropylene matrix component having a melt index of ; The bionic polar anchoring component comprises 1-8% by mass, wherein the bionic polar anchoring component is a block copolymer with a polypropylene block and catechol functional groups, and the melt index of the bionic polar anchoring component is as follows And (2) and And (3) with The ratio of (2) is 1.5 to 4.5; an interfacial migration assisting component in an amount of 0.1 to 1.5% by mass, the interfacial migration assisting component being 25 The surface tension is lower than that of the polypropylene matrix component at 25 Lower surface tension; Wherein, on the molding section of the bionic anchoring polypropylene material, the bionic polar anchoring component is arranged on the surface 15 of the bionic anchoring polypropylene material due to the surface tension gradient difference between the interface migration auxiliary component and the polypropylene matrix component To 50 A concentration-enriched layer is formed in the depth region of the polymer matrix, and the polypropylene block and the polypropylene matrix component realize the spatial positioning of catechol functional groups in the concentration-enriched layer through a co-crystallization structure formed by intermolecular entanglement.
  2. 2. The method for preparing the bionic anchoring polypropylene material for the automobile for improving the adhesive force of the water transfer printing coating according to claim 1, wherein the polypropylene matrix component is isotactic polypropylene or impact copolymer polypropylene with the isotacticity of not less than 96 percent and the melt index of 15 To 35 The number average molecular weight of the polypropylene block in the bionic polar anchoring component is 5000-15000, the mass ratio of catechol functional group in the bionic polar anchoring component is 10-25%, and the interface migration auxiliary component is 25 The lower surface tension is 18 To 24 And the difference in surface tension between the polypropylene and the polypropylene matrix component is not less than 8 。
  3. 3. The method for preparing the bionic anchoring polypropylene material for the automobile for improving the adhesive force of the water transfer printing coating according to claim 1, wherein the surface distribution density of catechol functional groups in the concentration-enriched layer is characterized in that The following quantitative relationship is satisfied: , wherein, Effective mass concentration of catechol functional groups in the concentration-enriched layer per unit area; a correlation constant preset for crystallization kinetics based on the polypropylene matrix component; for the average cooling rate in the molding cooling process, the unit is /S, passage of catechol functional groups And (3) with And the synergistic preparation of the nano-particles forms nano-order arrangement around the concentration-enriched layer.
  4. 4. The method for preparing the bionic anchoring polypropylene material for the automobile, which improves the adhesive force of the water transfer printing coating, according to claim 1, wherein catechol functional groups in the bionic polar anchoring component are selected from at least one of dopamine structural units, 3, 4-dihydroxyamphetamine structural units or catechol-based grafted polyethyleneimine units, and the catechol functional groups are covalently connected to the tail ends of the polypropylene blocks.
  5. 5. The method for preparing the bionic anchoring polypropylene material for the automobile for improving the adhesive force of the water transfer printing coating, according to claim 1, is characterized in that the melting point of the interface migration auxiliary component is lower than the crystallization starting temperature of the polypropylene matrix component, and the interface migration auxiliary component is in physical association with catechol functional groups in the bionic polar anchoring component through intermolecular van der Waals force and serves as a carrier for migration of the bionic polar anchoring component to the surface of the bionic anchoring polypropylene material.
  6. 6. The method for preparing the bionic anchoring polypropylene material for the automobile, which improves the adhesive force of the water transfer printing coating, according to claim 1, wherein the polypropylene matrix component further comprises a nucleating agent accounting for 0.2 to 0.5 percent of the total weight of the bionic anchoring polypropylene material, and the nucleating agent is used for improving the crystallization temperature of the polypropylene matrix component, so that the diffusion time of the bionic polar anchoring component in the concentration enriched layer is shortened to lock the molecular phase.
  7. 7. The method for preparing the bionic anchoring polypropylene material for the automobile for improving the adhesive force of the water transfer printing coating according to claim 1, wherein the bionic anchoring polypropylene material further comprises an antioxidant, a lubricant and a light stabilizer, and the total content of the antioxidant, the lubricant and the light stabilizer is not more than 1.2% of the total weight of the bionic anchoring polypropylene material.
  8. 8. The method for preparing the bionic anchoring polypropylene material for the automobile for improving the adhesive force of the water transfer printing coating according to claim 1, wherein the bionic polar anchoring component is prepared from maleic anhydride grafted polypropylene and catechol derivative containing amino groups through amidation reaction in a molten state, and the bionic polar anchoring component is 1645 Having an amide carbonyl characteristic infrared absorption peak.
  9. 9. The method for preparing the bionic anchoring polypropylene material for the automobile for improving the adhesion of the water transfer printing coating according to claim 1, wherein the bionic anchoring polypropylene material has a hundred-cell test adhesion between the surface and the water transfer printing ink of 0 level and 80 degrees in a surface untreated state Is soaked in water 240 The retention of post adhesion was 100%.
  10. 10. The method of claim 1, wherein the catechol functionality in the concentration-enriched layer is exposed to the surface of the biomimetic anchoring polypropylene material and is configured to form chemical chelation with the resin component in the water transfer ink.

Description

Preparation of bionic anchoring polypropylene material for improving adhesive force of water transfer coating for automobile Technical Field The invention belongs to the technical field of high polymer materials, and particularly relates to preparation of a bionic anchoring polypropylene material for an automobile, which improves the adhesive force of a water transfer coating. Background The current polypropylene resin has good mechanical property, lower density and excellent chemical stability, and is widely applied to automobile interiors and exterior trimming parts, because polypropylene belongs to typical nonpolar polymer materials, the surface energy is low, the interfacial chemical activity is insufficient, and when a water transfer printing decoration process is carried out, an ink layer generated by the activation of a water transfer printing film is difficult to form effective molecular chain entanglement or chemical bonding with a polypropylene substrate, so that edge curling or falling off of the decorative layer easily occurs in the drying shrinkage process, and the surface tension of the substrate is improved mainly through flame treatment, plasma modification or external surface treatment modes such as pre-coating polar primer, but the equipment investment and the production period are increased by the external procedures, the treatment effect is influenced by the placement time and the environmental humidity, and the quality stability of the production flow is restricted. In addition to improvement of external processing means, attempts are made to optimize a multilayer composite structure to improve interfacial bonding force, but the internal component control logic still has defects, for example, the Chinese patent application publication No. CN106626852B discloses a forming method of a laser water transfer composite film, which utilizes coating adhesives among multilayer films and matching vacuum aluminizing to realize interlayer bonding, although the adhesion strength among films is improved, the mechanism is limited by external interfacial physical adhesion, for an automobile injection molding part, the method cannot reach the problem of intrinsic nonpolar modification of a polypropylene substrate, the polar trapping phenomenon of polar components in the forming process is difficult to solve, the polar modification component is directly added into the polypropylene composition, the polar trapping restriction exists in a mode of improving the interfacial activity, the modified component tends to be buried inside the substrate in the melting cooling process due to thermodynamic incompatibility between the high-polarity modified component and the nonpolar polypropylene substrate, effective polar points are difficult to be exposed on the surface layer, excessive precipitation phenomenon is easy to be generated and weak interfacial layer is formed at the interface if the addition amount of the polar component is increased, so that interfacial stress cannot be effectively transmitted to the deep part of the substrate, and the adhesive force of the coating is deteriorated. Therefore, how to use the physical-chemical difference between the components to induce the polar sites to enrich the surface layer and construct a locking structure co-crystallized with the matrix body becomes the technical problem to be solved by the invention. Disclosure of Invention The invention provides a preparation of a bionic anchoring polypropylene material for an automobile for improving the adhesive force of a water transfer printing coating, which comprises the following components in percentage by mass based on 100% of the total weight of the bionic anchoring polypropylene material: a polypropylene matrix component having a melt index of ; The bionic polar anchoring component comprises 1-8% by mass, wherein the bionic polar anchoring component is a block copolymer with a polypropylene block and catechol functional groups, and the melt index of the bionic polar anchoring component is as followsAnd (2) andAnd (3) withThe ratio of (2) is 1.5 to 4.5; an interfacial migration assisting component in an amount of 0.1 to 1.5% by mass, the interfacial migration assisting component being 25 The surface tension is lower than that of the polypropylene matrix component at 25Lower surface tension; Wherein, on the molding section of the bionic anchoring polypropylene material, the bionic polar anchoring component is arranged on the surface 15 of the bionic anchoring polypropylene material due to the surface tension gradient difference between the interface migration auxiliary component and the polypropylene matrix component To 50A concentration-enriched layer is formed in the depth region of the polymer matrix, and the polypropylene block and the polypropylene matrix component realize the spatial positioning of catechol functional groups in the concentration-enriched layer through a co-crystallization structure formed by inter