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CN-122011513-A - Functional microsphere with core-shell structure, nylon material, and preparation methods and applications thereof

CN122011513ACN 122011513 ACN122011513 ACN 122011513ACN-122011513-A

Abstract

The invention relates to the technical field of high polymer materials, and discloses a core-shell structure functional microsphere, a nylon material, and a preparation method and application thereof. The core-shell structure functional microsphere comprises an inner core containing an ultraviolet absorbent and a shell layer coated on the surface of the inner core, wherein the shell layer is a hybridization network structure of polysiloxane and silicon dioxide. The invention melt blends the core-shell structure functional microsphere and nylon resin, realizes the dual functions integration of weather resistance and wear resistance with extremely low addition (0.1-1.0 wt%) and has the color difference of less than 2.0 after ultraviolet irradiation aging for 360 hours and the color difference of less than 0.8 after cross scraping, the performance of the technology is far more than that of the traditional system with the addition of common UV agent with the same or higher dosage, in addition, the technology is completely compatible with the existing double-screw extrusion and injection molding technology, the steps of complex, high energy consumption and high VOC discharge secondary spraying coating are omitted, and the comprehensive production cost and the environmental pollution are obviously reduced.

Inventors

  • Su Junzhao
  • CHEN XINTAI
  • YANG HAIMIN
  • JIA SIHAI

Assignees

  • 广东聚石化学股份有限公司

Dates

Publication Date
20260512
Application Date
20260120

Claims (10)

  1. 1. The core-shell structure functional microsphere is characterized by comprising an inner core containing an ultraviolet absorbent and a shell layer coated on the surface of the inner core, wherein the shell layer is of a hybridization network structure of polysiloxane and silicon dioxide.
  2. 2. The functionalized microsphere of claim 1, wherein the functionalized microsphere comprises a polysiloxane, an alkoxysilane, an ultraviolet absorber, a basic catalyst, and a surfactant.
  3. 3. The functionalized microsphere according to claim 2, wherein the polysiloxane has a molecular weight of 20000-30000Da; And/or the alkoxy silane is at least one selected from tetraethoxysilane, tetramethylsilicate and isopropyl silicate; and/or the basic catalyst is selected from ammonia water or organic amine; and/or the surfactant is at least one selected from tween, alkylphenol ethoxylates and block polyether.
  4. 4. A method for preparing the core-shell structure functional microsphere according to claim 2 or 3, comprising the following steps: S1, dissolving polysiloxane, alkoxy silane and an ultraviolet absorber in a solvent I to form an oil phase; S2, adding an oil phase into the water phase, homogenizing and emulsifying to obtain an emulsifying system; S3, adding an alkaline catalyst into the emulsifying system, and reacting to obtain the core-shell structure functional microsphere; Wherein the solvent I is selected from organic solvents with boiling point lower than 100 ℃ and water-insoluble, and the solvent II is selected from aqueous solutions of C1-C4 alkanols.
  5. 5. The method for preparing the core-shell structure functional microsphere according to claim 4, wherein in the step S1, the mass ratio of the polysiloxane, the alkoxy silane, the ultraviolet absorber and the solvent I is 1 (0.8-1.2): 1-1.5): 10-30; and/or, in the step S1, the content of the surfactant in the water phase is 0.5wt% to 1.5wt%; and/or in the step S2, the volume ratio of the water phase to the oil phase is (5-10): 1; And/or in the step S3, the concentration of the alkaline catalyst is 20-30wt%, and the volume ratio of the alkaline catalyst to the emulsifying system is 1 (10-20).
  6. 6. Use of the core-shell structure functional microsphere according to any one of claims 1-3 for preparing a polymer composite material.
  7. 7. A nylon material comprising the core-shell functional microsphere of any one of claims 1-3.
  8. 8. The nylon material according to claim 7, wherein the nylon material comprises, by mass, 98.5% -99% of nylon resin, 0.1% -1.0% of core-shell structure functional microspheres, 0.1% -0.5% of antioxidants and 0.2-0.8% of lubricants.
  9. 9. A method for preparing a nylon material according to claim 7 or 8, comprising the steps of: And mixing the preparation raw materials, carrying out melt blending by a double-screw extruder, and carrying out extrusion granulation to obtain the nylon material.
  10. 10. Use of the nylon material of claim 7 or 8 for the manufacture of automotive parts, photovoltaic modules, electrical and electronic housings or outdoor structural parts.

Description

Functional microsphere with core-shell structure, nylon material, and preparation methods and applications thereof Technical Field The invention relates to the technical field of high polymer materials, in particular to a core-shell structure functional microsphere, a nylon material, a preparation method and application thereof. Background Nylon (polyamide) is used as an important engineering plastic, and is widely applied to the fields of automobile parts, electronic and electric appliance shells, outdoor structural parts and the like by virtue of excellent mechanical strength, chemical corrosion resistance and good processing and forming properties. However, the amide groups in the nylon molecular chain are extremely sensitive to ultraviolet light. Under the condition of sunlight or artificial accelerated aging (such as a xenon lamp), ultraviolet light easily causes fracture and oxidation reaction of nylon molecular chains, so that the impact toughness of the material is reduced, the surface is cracked and the color is drifted, and the application of the material in a scene requiring long-term outdoor stability is severely restricted. The prior art generally improves the weatherability of nylon by adding small molecule ultraviolet absorbers (UVA) or Hindered Amine Light Stabilizers (HALS), but these small molecule adjuvants are prone to thermal decomposition and volatilization losses at the higher processing temperatures of nylon. More importantly, due to limited compatibility with nylon matrix and thermal movement of molecular chains, they can continuously migrate to the surface of the material during use of the article and eventually be washed away by rain, condensation or wiping solvents. In order to ensure that the product can still maintain acceptable color difference (such as delta E is less than or equal to 3.0) after aging for thousands of hours, the addition amount of UVA is greatly increased to 2-3 wt% or even higher. The cost is obviously increased, mechanical properties such as stretching, impact and the like of the nylon matrix are reduced, and the problems of mold pollution, product surface tackiness and the like are caused in the injection molding process, so that the production efficiency and the product appearance are affected. In addition, the nylon material has lower surface modulus, and is extremely easy to produce scratches and scratches during assembly, transportation, daily cleaning or contact with sand stone and metal tools, and obvious stress whitening phenomenon is shown. This not only impairs the quality of the product appearance, but also surface scratches seriously affect the adhesion of the coating to parts that require subsequent spraying or plating. The mainstream solution in the industry is to cover the surface of the nylon product formed by injection molding with a Polyurethane (PU) or Ultraviolet (UV) curable wear-resistant coating. However, the process requires expensive spraying production lines, drying ovens and VOC waste gas treatment devices, and has complex process flow and high energy consumption. And because the thermal expansion coefficients of the organic coating and the nylon matrix are obviously different, internal stress is easy to generate at the interface after the organic coating and the nylon matrix are subjected to cold and hot circulation at the ambient temperature, so that a paint film is cracked, peeled and even peeled, and the reliability is doubtful. Microcapsule technology has been attempted to encapsulate UVA to inhibit the migration and volatilization of small molecules of UVA. However, the microcapsule systems reported in the prior art, such as those based on melamine-formaldehyde resins or pure inorganic silica, generally have a shell with high rigidity, high brittleness and high glass transition temperature. In the screw extrusion process of nylon materials, the nylon materials are easy to be crushed and cracked by strong screw shearing force, so that the coating is invalid. In addition, the excessively dense inorganic silicon dioxide shell layer severely prevents UVA from being necessary and slowly diffused on the surface layer of the material needing to act while the UVA is restrained, so that the actual protection concentration of the surface layer is insufficient, and the weather-proof effect is discounted. More importantly, the traditional functional microcapsules are single in design thought, only aim at solving the weather-proof problem, cannot endow the surface of the material with scratch-resistant performance, and cannot realize multifunctional integration. Disclosure of Invention The present invention aims to solve at least one of the above technical problems in the prior art. Therefore, one of the purposes of the invention is to provide a functional microsphere with a core-shell structure. The second purpose of the invention is to provide a preparation method of the core-shell structure functional microsphere. The invention also a