Polymeric material and method of forming the same

Abstract

A polymeric material includes a hydrophobic polymer backbone, a side chain coupled to the hydrophobic polymer backbone, and an ionic pair coupled with the side chain of the hydrophobic polymer backbone. The ionic pair in combination with the hydrophobic polymer backbone is configured to be self-healing.

Description

POLYMERIC MATERIAL AND METHOD OF FORMING THE SAMETECHNICAL FIELD

[0001] The present invention relates generally to polymeric materials, and in particular embodiments, to self-healing surfaces.BACKGROUND

[0002] Thermal management is an increasingly important consideration in buildings and electronic devices. A significant portion of annual electricity consumption is devoted to air conditioning in buildings, and this usage continues to grow. For electronic devices, heat dissipation has become a critical issue as computing power increases, particularly with the expansion of artificial intelligence applications. Radiative cooling materials can offer a passive approach to heat dissipation by reflecting light in the 0.4 to 2.5 micron wavelength range and radiating light in the 8 to 13 micron range to outer space. However, outdoor environments expose these materials to harsh conditions including ultraviolet radiation, precipitation, wind, and physical damage. This can lead to degradation and reduced performance over time of the radiative cooling materials.SUMMARY OF THE INVENTION

[0003] Technical advantages are generally achieved by embodiments of this disclosure which include polymeric materials and methods of forming the same.

[0004] According to embodiments, a polymeric material includes a hydrophobic polymer backbone, a side chain coupled to the hydrophobic polymer backbone, and a water-insoluble ionic pair coupled with the side chain of the hydrophobic polymer backbone. The water-insoluble ionic pair is combination with the hydrophobic polymer backbone being configured to be self-healing.

[0005] Embodiments enable maintaining high radiative cooling performance while also exhibiting self-healing properties under harsh conditions. By combining high mid-infrared emissivity for radiative cooling with water-resistant self-healing properties, embodiments may provide advantageous materials with reliable and durable thermal management useful in, for example, consumer electronics coatings and building cooling applications.

[0006] In some embodiments, the water-insoluble ionic pair in combination with the hydrophobic polymer backbone is configured to be self-healing with a presence of ambient water. The ability to self-heal in the presence of water is an-i-advantage of embodiments, such as for outdoor applications where exposure to rain and humidity is common.

[0007] In some embodiments, wherein the water-insoluble ionic pair in combination with the hydrophobic polymer backbone is configured to be self- healing without a presence of ambient water.

[0008] In some embodiments, the water-insoluble ionic pair includes carbonhalide bonds, nitrogen-halide bonds, or phosphorus-halide bonds.

[0009] In some embodiments, the polymeric material further includes functional fillers. Embodiments may provide a platform of multi-functional radiative cooling material with tunable properties including thermal conductivity, mechanical strength, and flexibility by selecting additive monomers with different functionality and different polymer-filled structures.

[0010] In certain embodiments, the functional fillers include nanoparticles or microparticles of Si02, CuO, graphene oxide, ZnO, Ti02, silicon, a-quartz, silicon oxynitride, ZnS, or CdS. In certain embodiments, the functional fillers are distributed through the polymeric material in a raisin-in-bread structure. In certain embodiments, the functional fillers are distributed through the polymeric material in a layered structure. In certain embodiments, the functional fillers are distributed through the polymeric material in a 3D network structure.

[0011] In some embodiments, the polymeric material has emissivity greater than 0.9 for radiation wavelengths in a range of 8 pm to 13 pm. In some embodiments, the polymeric material has an absorption multiplier lower than 0.05 for radiation wavelengths in a range of 0.4 pm to 2.5 pm. In some embodiments, the polymeric material has a self-healing efficiency greater than 60% at a temperature less than 60 °C under a pressure of 1 atmosphere in a time range of less than one week. The spectral selectivity of embodiments may be advantageous for effective radiative cooling while minimizing solar heat gain.

[0012] In some embodiments, the hydrophobic polymer backbone is chosen from the group consisting of polydimethylsiloxane (PDMS), polyvinylidene fluoride (PVDF), and PVDF-hexafluoropropylene (PVDF-HFP) copolymer.

[0013] In some embodiments, a first water-insoluble ionic group of the waterinsoluble ionic pair is coupled with the side chain of the hydrophobic polymer backbone by a covalent bond, and where a second water-insoluble ionic group ofthe water-insoluble ionic pair is coupled with the side chain of the hydrophobic polymer backbone by dynamic ion interaction.

[0014] According to embodiments, a composite material structure includes a polymer matrix and a filler material distributed in the polymer matrix. The filler material includes nanoparticles or microparticles including a hydrophobic polymer backbone, a side chain coupled to the hydrophobic polymer backbone, and a water-insoluble ionic group coupled with the side chain of the hydrophobic polymer backbone by dynamic ion bonds. Embodiments enable controlling the filler / polymer matrix structures at nanometer and / or micrometer levels. This may be advantageous for achieving high performance in self-healing, thermal radiative cooling, and anti-ultraviolet aspects. Embodiments further enable strategic placement and distribution of additive particles within the polymer matrix, which can be advantageous by facilitating phonon transport and midinfrared range emission.

[0015] In certain embodiments, the filler material is distributed in the polymer matrix in a raisin-in-bread structure.

[0016] In certain embodiments, the filler material is distributed in the polymer matrix in a layered structure.

[0017] In certain embodiments, the filler material is distributed in the polymer matrix in a 3D network structure.

[0018] In some embodiments, the nanoparticles or microparticles include Si02, CuO, graphene oxide, ZnO, Ti02, silicon, a-quartz, silicon oxynitride, ZnS, CdS.

[0019] In some embodiments, the nanoparticles or microparticles includes nanoparticles of polydimethylsiloxane (PDMS), polyvinylidene fluoride (PVDF), or PVDF-hexafluoropropylene (PVDF-HFP) copolymer.

[0020] According to embodiments, a method for forming a self-healing surface includes forming a polymeric material by coupling a water-insoluble ionic group with a side chain of a hydrophobic polymer backbone, mixing the polymeric material with additive nanoparticles or microparticles, and applying the polymeric material over an exposed surface of a substrate. Embodiments enable different surface chemistry and physics properties as well as different degrees of hydrophobicity by employing different process methods.

[0021] In some embodiments, applying the polymeric material over the exposed surface of the substrate includes plasma polymerization. Using plasma polymerization to form the polymeric material may lower the hydrophobic property of the composite material structure.

[0022] In some embodiments, applying the polymeric material over the exposed surface of the substrate includes spin coating. Embodiments enable the creation of multi-layer coatings with different functional properties in each layer, providing advantageous flexibility in designing materials for specific thermal management applications.

[0023] In some embodiments, applying the polymeric material over the exposed surface of the substrate includes coating with a colloidal gel.Embodiments enable control over the chemical composition and nanostructure of the resulting coating, which may provide advantageous optimization of both the radiative cooling properties and the self-healing capabilities of the material.

[0024] In some embodiments, applying the polymeric material over the exposed surface of the substrate includes spray coating.

[0025] In some embodiments, applying the polymeric material over the exposed surface of the substrate includes flow coating.

[0026] In some embodiments, applying the polymeric material over the exposed surface of the substrate includes thermal spray coating.

[0027] In some embodiments, applying the polymeric material over the exposed surface of the substrate includes dip coating.

[0028] In some embodiments, mixing the polymeric material with additive nanoparticles or microparticles includes direct mixing or particle modification.

[0029] In certain embodiments, the particle modification includes using binder, surfactant, or amphiphile.

[0030] In certain embodiments, the binder, surfactant, or amphiphile includes polyvinyl alcohol, polyethylene glycol, epoxy resins, polysaccharides, sodium dodecyl sulfate, cetyltrimethylammonium bromide, Triton X-ioo, polysorbates, pluronic block copolymers, or stearic acid.

[0031] In some embodiments, the substrate includes a building material.

[0032] In some embodiments, the substrate is part of an electronic device housing or package.BRIEF DESCRIPTION OF THE DRAWINGS

[0033] For a more complete understanding of the present disclosure, and the advantages thereof, reference is now made to the following descriptions taken in conjunction with the accompanying drawings, in which:

[0034] Figures 1-2 illustrate schematic cross-sectional views of intermediate stages of a process for manufacturing a structure incorporating a polymeric material with self-healing properties, in accordance with various embodiments;

[0035] Figures 3-4 illustrate schematic cross-sectional views of intermediate stages of a self-healing process, in accordance with various embodiments;

[0036] Figure 5 illustrates a schematic diagram of example molecular structures of the polymeric material, in accordance with various embodiments;

[0037] Figures 6A, 6B, and 6C illustrate structural configurations of a polymeric material incorporating functional fillers, in accordance with various embodiments;

[0038] Figures 7, 8A, 8B, 8C, 8D, and 9 illustrate methods of forming composite material structures, in accordance with various embodiments; and

[0039] Figure 10 illustrates a process flow chart diagram of a method for forming a self-healing surface in accordance with various embodiments.

[0040] Corresponding numerals and symbols in the different figures generally refer to corresponding parts unless otherwise indicated. The figures are drawn to clearly illustrate the relevant aspects of the embodiments and are not necessarily drawn to scale.DETAILED DESCRIPTION OF ILLUSTRATIVE EMBODIMENTS

[0041] The making and using of embodiments of this disclosure are discussed in detail below. It should be appreciated, however, that the concepts disclosed herein can be embodied in a wide variety of specific contexts, and that the specific embodiments discussed herein are merely illustrative and do not serve to limit the scope of the claims. Further, it should be understood that various changes, substitutions and alterations can be made herein without departing from the spirit and scope of this disclosure as defined by the appended claims.

[0042] Radiative cooling polymers are materials that can effectively emit heat in the form of infrared radiation to achieve passive cooling. Current radiative cooling polymers such as polymethyl methacrylate (PMMA), polydimethylsiloxane (PDMS), polyvinylidene fluoride (PVDF), and PVDF- hexafluoropropylene (PVDF-HFP) contain a variety of chemical bonds and functional groups, including C-O, Si-O, and C-F bonds. These bonds can vibrate within the spectral range of the atmospheric transparent window of 8-13 microns. This results in strong absorption and emission of infrared radiation in this wavelength range. Additionally, simultaneous resonance with multiple vibrations can enhance this radiative cooling effect. The ability of these polymers to efficiently emit heat in the atmospheric transparency window makes them promising materials for passive cooling applications in buildings and electronic devices.

[0043] While radiative cooling polymers offer promising passive cooling capabilities, their performance can be significantly compromised by harsh environmental conditions. Several factors contribute to the degradation of these materials over time: Ultraviolet (UV) radiation exposure causes photooxidative aging in polymers. This process produces free radicals and reduces the molecular weight of the polymer chains, resulting in significant deterioration of many material properties overtime. The UV-induced degradation can alter the optical and thermal properties of the polymer, potentially reducing its radiative cooling effectiveness. Long-term exposure to water can damage polymer coatings through swelling. Water absorption can lead to changes in the structure and properties of the material, potentially affecting its radiative cooling performance and durability. Mechanical damage, such as scratches, can break the integrity of the polymer coating. These physical defects can disrupt the uniform surfacenecessary for optimal radiative cooling and may create pathways for further environmental degradation. Additionally, the formation of cracks in the coating can result in water leakage, potentially leading to corrosion of the underlying substrate. This not only compromises the protective function of the coating but can also significantly impair its radiative cooling capabilities. These environmental factors pose significant challenges to the long-term effectiveness and reliability of radiative cooling polymer coatings in real-world applications. Addressing these issues is crucial for developing durable and high-performance radiative cooling materials for use in building and electronic device thermal management. As such, self-healing properties are desirable to extend the lifespan and maintain the effectiveness of radiative cooling materials in practical applications.

[0044] While research has been conducted on radiative cooling materials and self-healing coatings separately, integrating both capabilities into a single material system remains a challenge, particularly for applications requiring self- healing in the presence of water. There is a need for durable, multi-functional materials that can provide both efficient radiative cooling and self-repair under ambient conditions to protect underlying substrates and maintain long-term performance.

[0045] To address the challenges posed by harsh environmental conditions, a novel approach to radiative cooling polymers is proposed that incorporates self- healing capabilities. Embodiments include stable and durable polymers that maintain high radiative cooling performance while also exhibiting self-healing properties under harsh conditions. A selection of a polymer backbone with high absorption and emission in the mid-infrared range may achieve effective radiative cooling performance by efficiently emitting heat in the atmospheric transparency window of 8-13 microns. Modifications of the selected polymer backbone with self-healing ionic compounds may enable the material to autonomously repair damage caused by environmental factors. The self-healing mechanism may function in the presence of water or in the absence of water. In various embodiments, the self-healing process can occur through dynamic ionic interactions that are not disrupted by the presence of water. As such, embodiments may provide advantages over other self-healing mechanisms, such as those based on imine bonds, boronate ester bonds, or hydrogen bonding,which can be negatively affected by water. By combining high mid-infrared emissivity for radiative cooling with water-resistant self-healing properties, embodiments may provide a monolithic material with reliable and durable thermal management useful in, for example, consumer electronics coatings and building cooling applications. The ability to self-heal in the presence of water is advantageous for outdoor applications where exposure to rain and humidity is common. Embodiments may thus provide potential solutions for long-term preservation of radiative cooling performance under real-world environmental conditions, addressing the durability issues that have limited the practical application of radiative cooling polymers.

[0046] Various embodiments of the disclosure include polymeric material systems that provide radiative cooling and self-healing capabilities. The polymeric material comprises a hydrophobic polymer backbone with waterinsoluble ionic groups coupled to side chains. This enables self-repair through, for example, dynamic ionic interactions. In one or more embodiments, the material exhibits high mid-infrared emissivity for radiative cooling while maintaining low absorption in the visible and near-infrared spectrum to minimize solar heat gain. Additionally, by selecting additive monomers with different functionality and different polymer-filled structures, embodiments provide a platform of multifunctional radiative cooling material with tunable properties including thermal conductivity, mechanical strength, and flexibility.

[0047] Various structural configurations and fabrication methods are described that allow tuning of the thermal, mechanical, and surface properties. The figures referenced in the following description schematically illustrate example structures, compositions, and manufacturing approaches for the polymeric material system. It should be understood that aspects may be implemented in many alternate forms and combinations beyond those specifically depicted and described herein.

[0048] Embodiments of the disclosure are described in the context of the accompanying drawings. Embodiments of a process for manufacturing a structure incorporating a polymeric material with self-healing properties will be described using Figures 1-4. Embodiments of molecular structures for polymeric material will be described using Figure 5. Embodiments of different structural configurations of polymeric materials incorporating functional fillers will bedescribed using Figures 6A, 6B, and 6C. Embodiments of methods for forming composite material structures comprising a polymer matrix with or without additive filler material will be described using Figures 7, 8A, 8B, 8C, 8D, and 9. An embodiment of a method for forming a self-healing surface will be described using Figure 10.

[0049] Figure 1 illustrates a schematic cross-sectional view of a structure too including a substrate 102. In various embodiments, the substrate 102 is a building material such as concrete, metal, or wood, or is part of an electronic device housing or package. As such, the substrate 102 comprises any suitable material including metals, plastics, polymer-containing compounds, wood, concrete, stone, the like, or a combination thereof.

[0050] In Figure 2, following from Figure 1, a coating 104 is applied to the surface of the substrate 102. The coating 104 comprises a polymeric material system that provides both radiative cooling and self-healing functionality. In various embodiments, the polymeric material of coating 104 includes a hydrophobic polymer backbone with water-insoluble ionic groups coupled to side chains. In an embodiment, the hydrophobic polymer backbone is selected from materials containing C-F and / or Si-0 bonds such as polydimethylsiloxane (PDMS), polyvinylidene fluoride (PVDF), or PVDF-hexafluoropropylene (PVDF- HFP) copolymer. However, any suitable material may be used.

[0051] In various embodiments, applying the polymeric material over the exposed surface of the substrate 102 comprises plasma polymerization, spin coating, coating with a colloidal gel, spray coating flow coating, thermal spray coating, dip coating, the like, or a combination thereof. However, any suitable process may be used to form the coating 104.

[0052] The ionic groups attached to the side chains, which may be water nonsoluble, allow for self-healing, such as through dynamic ionic interactions. The ionic liquid groups may be non-flammable and non-volatile, thereby providing enhanced thermal stability and environmental safety. In various embodiments, the ionic groups comprise carbon-halide bonds, nitrogen-halide bonds, or phosphorus-halide bonds. In various embodiments, the ionic groups are coupled to the side chains by dynamic ion interaction, by covalent bonds, or a combination thereof. However, any suitable chemical interactions may couple the ionic groups with the side chains.

[0053] In one or more embodiments, the coating 104 also incorporates functional fillers to enhance radiative cooling performance. These fillers may include nanoparticles or microparticles of materials such as silicon dioxide, titanium dioxide, zinc oxide, or other inorganic or polymeric substances. In various embodiments, mixing the polymeric material with additive nanoparticles or microparticles comprises direct mixing or particle modification. In some embodiments, particle modification for mixing the polymeric material with additive nanoparticles or microparticles is performed using a binder, surfactant, or amphiphile such as polyvinyl alcohol, polyethylene glycol, epoxy resins, polysaccharides, sodium dodecyl sulfate, cetyltrimethylammonium bromide, Triton X-100, polysorbates, pluronic block copolymers, stearic acid, the like, or a combination thereof.

[0054] The combination of the hydrophobic polymer backbone, ionic side groups, and functional fillers provides the coating 104 with properties such as emissivity in the high mid-infrared range, high solar reflectivity, and self-healing. In various embodiments, to achieve good radiative cooling efficiency, the material of the coating 104 possesses an absorption multiplier, where the absorption multiplier is determined by the absorption coefficient a of the material of the coating 104 multiplied by the thickness of the coating 104, higher than 0.025 for radiation with a wavelength in a range of 8 pm to 13 pm. The material of the coating 104 may also have emissivity greater than 0.9 for radiation with a wavelength in a range of 8 pm to 13 pm. The material of the coating 104 may further have an absorption multiplier lower than 0.05 for radiation with a wavelength in a range of 0.4 pm to 2.5 pm. This spectral selectivity may be advantageous for effective radiative cooling while minimizing solar heat gain.

[0055] Figure 3 illustrates the structure 100 after the formation of a crack 110 in the coating 104. This crack 110 may result from various environmental factors or mechanical stresses experienced during use. In an embodiment, the crack 110 extends partially through the thickness of the coating 104. In other embodiments, the crack 110 may extend fully through the coating 104 to expose the underlying substrate 102.

[0056] The presence of the crack 110 demonstrates a scenario where the self- healing properties of the polymeric material of the coating 104 become advantageous. The water-insoluble ionic groups coupled to the side chains of thehydrophobic polymer backbone enable a self-repair mechanism, such as through dynamic ionic interactions. In various embodiments, this self-healing process can occur both in the presence and absence of ambient water, providing versatility across different environmental conditions and enabling long-term functioning of the polymer coating as a reliable and durable coating against a harsh environment.

[0057] The self-healing efficiency of the coating 104 is characterized by its ability to restore its structural integrity and functional properties after damage. In one or more embodiments, the polymeric material exhibits a self-healing efficiency greater than 60% at temperatures below 6o°C under atmospheric pressure (in other words, under a pressure of about 1 atm). The self-healing efficiency may be determined by the Young modulus E before and after the breaking of the polymeric material and the subsequent healing of the polymeric material, where the self-healing efficiency = Eafter / Ebefore. In some embodiments, the self-healing occurs within about one week. This self-healing capability helps maintain the radiative cooling performance of the coating 104 over time, even when subjected to mechanical damage or environmental stresses.

[0058] Figure 4 illustrates the structure 100 after the self-healing process has occurred, addressing the crack 110 shown in Figure 3. The coating 104 now displays a healed portion 106 where the crack was previously located. In various embodiments, the healed portion 106 represents the area where the dynamic ionic interactions have facilitated the reconnection of the polymer chains across the damaged region. Portions of degraded material (e.g., rust or the like) may protrude from the top surface of the structure too on either side of the healed portion 106.

[0059] The self-healing process results in the restoration of the integrity of the coating. The self-healing process may leave a crack remnant 112 that may be visible but does not compromise the functionality of the coating. In an embodiment, the crack remnant 112 is a superficial mark on the surface of the coating 104, while the underlying material has regained its structural continuity. The healed portion 106 demonstrates the effectiveness of the water-insoluble ionic groups in facilitating the self-repair mechanism.

[0060] In one or more embodiments, the healed portion 106 exhibits properties similar to the surrounding undamaged coating material. This includesmaintaining the radiative cooling capabilities, such as having an absorption multiplier higher than 0.025 and emissivity greater than 0.9 for radiation with a wavelength in a range of 8 pm to 13 pm and having an absorption multiplier lower than 0.05 for radiation with a wavelength in a range of 0.4 pm to 2.5 pm. The self-healing process thus preserves the ability of the coating to reflect solar radiation and emit infrared radiation effectively, ensuring continued thermal management performance. The healed portion 106, like the coating 104, may also exhibit hydrophobicity, which maybe due to the presence of the hydrophobic polymer backbones in the self-healing material.

[0061] The restoration of the integrity of the coating 104 in the healed portion 106 also helps to protect the underlying substrate 102 from potential environmental damage or corrosion that could occur if the crack remained unrepaired. This self-healing capability contributes to the longevity and sustained performance of the coating 104 in various applications, including building materials and electronic device housings. As such, the coating 104 is advantageous for managing heat in building coatings and customer electronics packaging and for protecting underlying material (e.g., a metal) from corrosion.

[0062] Figure 5 illustrates a schematic diagram of example molecular structures of the polymeric material used in the coating 104. Illustrated chemicals may contribute to both the radiative cooling and self-healing properties of the material.

[0063] The left side of Figure 5 illustrates various example hydrophobic polymer backbones. These may form the main chain of the polymer. In various embodiments, this backbone is composed of materials such as polydimethylsiloxane (PDMS) and / or fluorinated polymers such as polyvinylidene fluoride (PVDF) or PVDF-hexafluoropropylene (PVDF-HFP) copolymer. These materials may be selected for their strong absorption and emission characteristics in the mid-infrared range, particularly in a range of 8 to 13 micrometers, which maybe advantageous for effective radiative cooling. These materials may also have low absorption in the ultraviolet (UV) to visible light range, thereby providing higher solar reflectivity and enabling longer service time than regular coatings without such properties.

[0064] Extending from the polymer backbone are side chains, represented by branching structures in the diagram. At the ends of these side chains are water-insoluble ionic groups. In an embodiment, these ionic groups may include moieties such as imidazolium, pyridinium, quaternary ammonium, sulfonate, phosphonium, or carboxylate. The counterions associated with these groups may include halide anions or species containing carbon-halide bonds, which can further enhance the emissivity of the material in the infrared range. As illustrated by Figure 5, the polymeric material may include such chemicals as polyvinylidene fluoride (PVDF), polyfvinylidene fluoride-co-hexafluoropropylene) (PVDF-HFP), polydimethylsiloxane (PDMS), polyvinyl fluoride (PVF), fluorinated ethylene propylene (FEP), polychlorotrifluoroethylene, polyperfluoropropylene oxide glycol, the like, or a combination thereof.

[0065] The diagram also illustrates the dynamic ionic interactions between the water-insoluble ionic groups. These interactions are represented by dashed lines connecting different ionic groups. In one or more embodiments, these dynamic ionic interactions are responsible for the self-healing capability of the material. When a crack or damage occurs, these ionic interactions can reform across the damaged area, facilitating the reconnection of polymer chains and restoring the integrity of the material.

[0066] The molecular structure illustrated in Figure 5 demonstrates how the various components work together to provide a material that combines efficient radiative cooling with self-healing capabilities, suitable for applications in building coatings and electronic device thermal management.

[0067] Figures 6A, 6B, and 6C illustrate different structural configurations of the polymeric material of the coating 104 (see above, Figures 2-4) incorporating functional fillers. These configurations demonstrate various approaches to improving the thermal management properties of the material. Controlling the filler / polymer matrix structures at nanometer and / or micrometer levels maybe advantageous for achieving high performance in self-healing, thermal radiative cooling, and anti-ultraviolet aspects. For example, the strategic placement and distribution of additive particles within the polymer matrix can facilitate phonon transport and mid-infrared range emission. Advanced dispersal techniques, including mixing, ultrasonication, and in-situ chemical reactions can be used achieve a homogeneous distribution of additive nanoparticles within the polymer matrix. Various forming techniques may be used to achieve the structural integrity and desired thermal properties of the composite coating material, suchas spray coating, flow coating, thermal spray coating, spin coating, dip coating, plasma polymerization, the like, or a combination thereof.

[0068] Figure 6A illustrates a raisin-in-bread structure 120 of a polymer matrix 124 incorporating functional fillers 128. This configuration represents one approach to distributing fillers within a polymer material to enhance radiative cooling properties while maintaining self-healing capabilities.

[0069] In the structure illustrated by Figure 6A, the functional fillers 128 are dispersed throughout the polymer matrix 124 in a manner reminiscent of raisins in a loaf of bread, hence the name. The polymer matrix 124, which in various embodiments comprises the hydrophobic polymer backbone with water-insoluble ionic groups attached to side chains, forms the continuous phase or "bread" of the material. The functional fillers 128, illustrated as spherical or spheroid particles of varying sizes, are analogous to the "raisins" embedded within this continuous phase.

[0070] The distribution of fillers in the raisin-in-bread structure 120 may be generally random and homogeneous. In various embodiments, the concentration of fillers can be adjusted to achieve specific properties. At lower concentrations, the filler particles of the functional fillers 128 may be completely isolated from one another, fully surrounded by the polymer matrix 124. As the concentration increases, some filler particles of the functional fillers 128 may come into contact with each other, potentially forming small clusters or chains within the polymer matrix 124.

[0071] The raisin-in-bread structure 120 offers several advantages for the performance of the polymeric material. In one or more embodiments, this configuration allows for a uniform distribution of radiative cooling properties throughout the material. Each filler particle contributes to the ability of the material to reflect solar radiation (e.g., ultraviolet (UV) light) and emit infrared radiation, enhancing the overall cooling effect as well as limiting polymer UV exposure and extending the service time of the coating. The random distribution may be useful for promoting the consistency of these properties across the entire volume of the material, avoiding localized hot spots or areas of reduced performance.

[0072] Additionally, the raisin-in-bread structure maintains the flexibility and self-healing capabilities of the polymeric material. The continuous polymermatrix 124, with its dynamic ionic interactions, remains largely uninterrupted, allowing for the movement and reconnection of polymer chains in response to damage. In an embodiment, even areas with a high concentration of fillers retain some degree of self-healing ability, as the polymer matrix 124 still forms a continuous phase around the filler particles of the functional fillers 128.

[0073] The size and nature of the filler particles of the functional fillers 128 can be varied to tune the properties of the material. In various embodiments, the filler particles comprise nanoparticles or microparticles of inorganic materials such as Si02, CuO, graphene oxide, ZnO, TiCh, silicon, a-quartz, silicon oxynitride, ZnS, CdS, or nanoparticles or microparticles of organic materials such as PDMS, PVDF, or PVDF-HFP, the like, or a combination thereof.

[0074] The raisin-in-bread structure 120 also offers practical advantages in terms of manufacturability. In one or more embodiments, this configuration can be achieved through relatively simple mixing and dispersion processes, making it amenable to large-scale production methods. The ease of fabrication makes the raisin-in-bread structure a viable option for applications in both building coatings and electronic device thermal management where cost-effective production is a consideration.

[0075] Figure 6B illustrates a layered structure 130 of the polymeric material incorporating functional fillers. This arrangement represents an organized approach to distributing fillers within the polymer matrix, which may be advantageous for tailoring the radiative cooling and mechanical properties of the material.

[0076] In the layered structure 130, the functional fillers are concentrated in alternating layers within the polymeric material. Figure 6B illustrates a series of filler-rich layers 138 interspersed with polymer-rich layers 134. This stratified arrangement creates a repeating pattern throughout the thickness of the material.

[0077] Within each filler-rich layer 138, the particles may form a percolated arrangement. In various embodiments, this means that the filler particles are in close proximity or direct contact with each other, creating a continuous network within the filler-rich layer 138. This network of fillers can enhance the radiative cooling properties within these specific regions. The polymer-rich layers 134, in contrast, comprise the hydrophobic polymer backbone with water-insoluble ionicgroups attached to side chains, which may maintain the self-healing capabilities of the layered structure 130.

[0078] In some embodiments, there is no contact between fillers in adjacent filler-rich layers 138 of the layered structure 130. The polymer-rich layers 134 act as barriers, effectively isolating each filler-rich layer 138 from the others. This separation allows for precise control over the distribution and concentration of fillers throughout the material. The layered configuration offers several advantages and enables fine-tuning of the properties of the material. In one or more embodiments, the thickness and number of layers can be controlled to tune properties including thermal conductivity, radiative cooling power, mechanical strength, flexibility, and transparency. For example, increasing the number of filler-rich layers 138 can enhance the overall radiative cooling performance, while adjusting the thickness of the polymer-rich layers 134 can maintain flexibility and self-healing properties.

[0079] This layered structure 130 also allows for directional control of thermal properties. In an embodiment, heat transfer maybe more efficient parallel to the layers than perpendicular to them. This anisotropic behavior can be advantageous in certain applications where directional heat dissipation is desired. The layered structure 130 provides flexibility in material design. In various embodiments, different types of fillers can be used in separate layers, allowing for a combination of functionalities within a single coating. For instance, one set of layers might contain fillers optimized for radiative cooling in the 8 to 13 micrometer range, while another set could include fillers that enhance UV reflection or mechanical strength.

[0080] From a manufacturing perspective, the layered structure 130 can be achieved through various fabrication methods. In one or more embodiments, techniques such as layer-by-layer deposition, co-extrusion, or advanced 3D printing processes may be employed to create the alternating filler-rich layers 138 and polymer-rich layers 134. These methods offer precise control over the composition and properties of the material.

[0081] The layered configuration maintains the self-healing capabilities of the material, particularly within the polymer-rich layers 134. In various embodiments, the dynamic ionic interactions of the water-insoluble ionic groups attached to the polymer side chains remain active in these regions, allowing forthe reconnection of polymer chains in response to damage. In an embodiment, the self-healing process may be more pronounced in the polymer-rich layers 134, while the filler-rich layers 138 contribute to the radiative cooling performance. The layered structure 130 illustrated in Figure 6B provides a sophisticated approach to balancing and optimizing the radiative cooling and self-healing properties of the polymeric material. This configuration offers enhanced control over material properties, making it suitable for applications in building coatings and electronic device thermal management where specific performance characteristics are required.

[0082] Figure 6C illustrates a 3D network structure 140 of a polymer matrix 144 incorporating functional fillers 148. This sophisticated arrangement represents a complex approach to distributing fillers within the polymer matrix 144, offering unique advantages for enhancing both radiative cooling efficiency and material properties. In some embodiments of the 3D network structure 140, a functional filler 148 forms a continuous three-dimensional interconnected network throughout the polymer matrix 14. This network of the functional fillers 148 maybe fully embedded within the polymer matrix 144, creating a composite structure with interpenetrating phases.

[0083] The 3D network of the functional fillers 148 is represented in Figure 6C as an interconnected web-like structure that extends in all directions within the 3D network structure 140. The polymer matrix 144, which may comprise a hydrophobic polymer backbone with water-insoluble ionic groups attached to side chains, fills the remaining space, encapsulating the 3D network of the functional fillers 148. This polymer phase maintains continuity throughout the material, ensuring that the self-healing properties are preserved. The 3D network structure 140 offers several significant advantages for the performance of the polymeric material.

[0084] In one or more embodiments, the continuous network formed by the functional fillers 148 can enhance the thermal conductivity of the material. This improved thermal conductivity can facilitate more efficient heat transfer within the material, potentially enhancing its overall radiative cooling performance by allowing heat to be more readily conducted to the surface for emission. The interconnected nature of the network of the functional fillers 148 also provides mechanical reinforcement to the polymeric material of the polymer matrix 144.

[0085] In various embodiments, this can lead to improved strength and dimensional stability without significantly compromising flexibility. The enhanced mechanical properties can be particularly beneficial for applications requiring durability under thermal cycling or mechanical stress.

[0086] In an embodiment, different fillers can be selected and included as part of the functional fillers 148 to complement the radiative cooling properties of the primary network. For example, a first filler of the functional fillers 148 could be optimized for thermal conductivity, while a second filler of the functional fillers 148 could be chosen for a high emissivity in the 8 to 13 micrometer wavelength range, which could further enhance the radiative cooling efficiency of the material. The 3D network structure 140 maintains the self-healing capabilities of the polymeric material, as the continuous polymer matrix 144 with its dynamic ionic interactions remains present throughout the structure.

[0087] In one or more embodiments, the self-healing process may occur within the polymer-rich regions of the polymer matrix 144 between the filler network and particles of the functional fillers 148. The presence of the 3D network of the functional fillers 148 might influence the kinetics of the self- healing process, potentially providing additional pathways for material flow and reconnection in damaged areas. In various embodiments, techniques such as in- situ polymerization around a preformed filler network, templating methods, or advanced additive manufacturing processes maybe employed to achieve this structure.

[0088] The unique properties offered by the 3D network structure 140 may be advantageous for certain high-performance applications. The 3D network structure 140 also offers opportunities for multifunctional material design. In an embodiment, the continuous network of the functional fillers 148 could be composed of a material that not only enhances thermal properties but also provides additional functionalities such as electrical conductivity or electromagnetic shielding. This multi-functionality can be particularly valuable in electronic device thermal management applications.

[0089] Overall, the 3D network structure 140 illustrated in Figure 6C represents an advanced approach to designing polymeric materials with enhanced radiative cooling and self-healing properties. This configuration offers a unique combination of thermal management, mechanical reinforcement, andfunctional versatility, making it suitable for demanding applications in both building coatings and electronic device thermal management where high performance across multiple parameters is required.

[0090] Figures 7, 8A, 8B, 8C, 8D, and 9 illustrate various methods of forming composite material structures comprising a polymer matrix with or without additive filler material (e.g., the structures described above with reference to Figures 2-4, 6A, 6B, and 6C), in accordance with some embodiments. Different process methods can be used to produce significantly different surface chemistry and physics properties, as well as different degrees of hydrophobicity. For example, when using a spin coating method to fabricate a layered structure 130 (see above, Figure 6B), the hydrophobicity of the coating may depend on the top layer chemical properties. As another example, using plasma polymerization to fabricate a composite material structure may greatly lower the hydrophobic property of the composite material structure. Various degrees of surface roughness created by different process methods may achieve different properties. For example, a composite material structure comprising a polymer matrix with a rough surface area provides a larger surface area that may lead to better radiative cooling performance. A rough surface of a hydrophobic polymer coating may result in a larger contact angle, thereby enhancing hydrophobicity.

[0091] Figure 7 illustrates a schematic representation of a plasma polymerization process for forming a coating with tunable thermal management properties, self-healing properties, and hydrophobicity, in accordance with various embodiments. The process involves the use of a polymer substrate 202, monomers 204, and plasma polymerized molecules 206. In various embodiments, the polymer substrate 202 serves as the base material onto which the coating will be applied, such as the substrate 102 described above with respect to Figure 1. In some embodiments, the monomers 204 comprise comprises the materials of the coating 104 described above with respect to Figures 2 and 5, filler particles of functional filler materials as described above with respect to Figure 6A, or a combination thereof.

[0092] The monomers 204 are introduced into a plasma chamber over the polymer substrate 202. Next, energy is supplied from a power supply (e.g., an RF, DC, or microwave power supply) to generate a plasma 210, which comprises various electrons, ions, radicals, UV radiation, the like or a combination thereof.The plasma 210 activates the monomers 204, causing them to fragment and recombine into plasma polymerized molecules 206. As the plasma polymerization process continues, the plasma polymerized molecules 206 deposit onto the surface of the polymer substrate 202, thereby forming a thin film coating. The properties of this coating, including its surface chemistry and hydrophobicity, can be tuned by adjusting various process parameters such as the type of monomers used, plasma power, and deposition time. In one or more embodiments, the plasma polymerization technique allows for precise control over the characteristics of the coating. For example, by selecting appropriate monomers 204 and plasma conditions, the hydrophobicity of the resulting coating can be tailored to meet specific requirements for radiative cooling applications. In an embodiment, the use of plasma polymerization may lower the hydrophobic property of the coating compared to other methods.

[0093] Figures 8A-8D illustrate perspective views of intermediate stages of for forming a coating with tunable thermal management properties, self-healing properties, and hydrophobicity, in accordance with various embodiments. Figure 8A illustrates a chuck 500, which serves as the base for the spin coating process. In various embodiments, the chuck 500 is typically a flat, circular platform that can rotate at high speeds. A substrate 510 is placed on the chuck 500. In various embodiments, this substrate 510 is a building material, a component of an electronic device, or any other surface intended for application of the radiative cooling and self-healing coating, as described above for substrate 102 with respect to Figure 1. Figure 8A further illustrates a deposition of the coating material 520 onto the center of the substrate 510. The coating material 520 comprises, for example, the polymeric solution containing the hydrophobic polymer backbone with water-insoluble ionic groups attached to side chains, and may also include functional fillers for enhanced radiative cooling properties.

[0094] Figures 8B, 8C, and 8D illustrate the spinning process. The chuck 500 rotates at high speed, causing the coating material 520 to spread evenly across the surface of the substrate 510 due to centrifugal force. This is illustrated as the coating material 520 becoming progressively flatter and more spread out over the substrate 510 in Figures 8B, 8C, and 8D. This rotation continues until the desired thickness of the coating is achieved. In one or more embodiments, the spin coating method allows for precise control over the thickness and uniformity of thecoating. The final properties of the coating, including its hydrophobicity and radiative cooling efficiency, can be tuned by adjusting parameters such as the rotation speed, acceleration, and the concentration of the coating solution.

[0095] When using spin coating to fabricate a layered structure, the hydrophobicity of the coating may depend on the chemical properties of the top layer. In an embodiment, this method allows for the creation of multi-layer coatings with different functional properties in each layer, providing flexibility in designing materials for specific thermal management applications.

[0096] Figure 9 illustrates a schematic representation of a sol-gel process for forming a coating with tunable thermal management properties, self-healing properties, and hydrophobicity, in accordance with various embodiments. The process begins with step 600, which involves the preparation of a solution of precursors and catalysts. In various embodiments, these precursors may include organosilanes or other compounds that can form the hydrophobic polymer backbone, as well as compounds containing the water-insoluble ionic groups that will be attached to the side chains.

[0097] Next, step 610 represents the condensation reaction, where the precursors begin to form a colloidal solution, or sol. During this stage, the molecules start to link together, forming larger structures but remaining suspended in the liquid medium.

[0098] In step 620, following from step 610, the sol undergoes gelation, transforming into a gel. This gel may be an interconnected, porous network of the polymeric material suspended in a liquid phase. The gel structure incorporates both the hydrophobic polymer backbone and the water-insoluble ionic groups that provide the self-healing functionality.

[0099] Next, step 630 illustrates the application of the gel to a substrate. In one or more embodiments, this can be achieved through various methods such as dip coating, spin coating, or electrodeposition, depending on the nature of the substrate and the desired coating properties.

[0100] Step 640, following from step 630, involves drying and calcination of the applied coating. During this stage, the liquid phase is removed, and the gel network collapses to form a dense, solid film. The calcination process can also be used to fine-tune the properties of the coating, such as its porosity, hydrophobicity, and radiative cooling efficiency. In an embodiment, the sol-gelmethod allows for precise control over the chemical composition and nanostructure of the resulting coating. This level of control enables the optimization of both the radiative cooling properties and the self-healing capabilities of the material. The sol-gel technique offers several advantages, including the ability to create coatings with high purity and homogeneity, as well as the potential for low-temperature processing. It also allows for the incorporation of various functional fillers or additives during the sol preparation stage, which can enhance the radiative cooling performance of the final coating. By carefully adjusting the parameters of the sol-gel process, such as precursor concentrations, pH, and processing temperatures, the surface properties and hydrophobicity of the coating can be tailored to meet specific requirements for thermal management applications in consumer electronics and building materials.

[0101] Figure 10 illustrates a process flow chart diagram of a method 1000 for forming a self-healing surface, in accordance with some embodiments. In step 1002, a polymeric material is formed by coupling a water-insoluble ionic group with a side chain of a hydrophobic polymer backbone, as described above with respect to Figures 2 and 5.

[0102] In step 1004, the polymeric material is mixed with additive nanoparticles or microparticles, as described above with respect to Figures 7, 8A, 8B, 8C, 8D, and 9. In some embodiments, mixing the polymeric material with additive nanoparticles or microparticles includes direct mixing or particle modification. In some embodiments, the particle modification includes using binder, surfactant, or amphiphile. In some embodiments,

[0103] In step 1006, the polymeric material is applied over an exposed surface of a substrate, as described above with respect to Figure 2. In some embodiments, applying the polymeric material over the exposed surface of the substrate includes plasma polymerization, spin coating, coating with a colloidal gel, spray coating flow coating, thermal spray coating, or dip coating. In some embodiments, the binder, surfactant, or amphiphile includes polyvinyl alcohol, polyethylene glycol, epoxy resins, polysaccharides, sodium dodecyl sulfate, cetyltrimethylammonium bromide, Triton X-100, polysorbates, pluronic block copolymers, or stearic acid.

[0104] Example embodiments of the invention are described below. Other embodiments can also be understood from the entirety of the specification as well as the claims filed herein.

[0105] Example 1. A polymeric material including: a hydrophobic polymer backbone; a side chain coupled to the hydrophobic polymer backbone; and a water-insoluble ionic pair coupled with the side chain of the hydrophobic polymer backbone, the water-insoluble ionic pair in combination with the hydrophobic polymer backbone being configured to be self-healing.

[0106] Example 2. The polymeric material of example 1, where the waterinsoluble ionic pair in combination with the hydrophobic polymer backbone is configured to be self-healing with a presence of ambient water.

[0107] Example 3. The polymeric material of example 1 or 2, where the waterinsoluble ionic pair in combination with the hydrophobic polymer backbone is configured to be self-healing without a presence of ambient water.

[0108] Example 4. The polymeric material of any one of examples 1 3, where the water-insoluble ionic pair includes carbon-halide bonds, nitrogen-halide bonds, or phosphorus-halide bonds.

[0109] Example 5. The polymeric material of any one of examples 1 4, further including functional fillers.

[0110] Example 6. The polymeric material of example 5, where the functional fillers include nanoparticles or microparticles of SiO2, CuO, graphene oxide, ZnO, Ti02, silicon, a-quartz, silicon oxynitride, ZnS, or CdS.

[0111] Example 7. The polymeric material of example 5 or 6, where the functional fillers are distributed through the polymeric material in a raisin-in- bread structure.

[0112] Example 8. The polymeric material of example 5 or 6, where the functional fillers are distributed through the polymeric material in a layered structure.

[0113] Example 9. The polymeric material of example 5 or 6, where the functional fillers are distributed through the polymeric material in a 3D network structure.

[0114] Example 10. The polymeric material of any one of examples 1---9, where the polymeric material has emissivity greater than 0.9 for radiation wavelengths in a range of 8 pm to 13 pm.

[0115] Example 11. The polymeric material of any one of examples 1 10, where the polymeric material has an absorption multiplier lower than 0.05 for radiation wavelengths in a range of 0.4 pm to 2.5 pm.

[0116] Example 12. The polymeric material of any one of examples 1 - 11, where the polymeric material has a self-healing efficiency greater than 60% at a temperature less than 60 °C under a pressure of 1 atmosphere in a time range of less than one week.

[0117] Example 13. The polymeric material of any one of examples 1 12, where the hydrophobic polymer backbone is chosen from the group consisting of polydimethylsiloxane (PDMS), polyvinylidene fluoride (PVDF), and PVDF- hexafluoropropylene (PVDF-HFP) copolymer.

[0118] Example 14. The polymer material of any one of examples 1 13, where a first water-insoluble ionic group of the water-insoluble ionic pair is coupled with the side chain of the hydrophobic polymer backbone by a covalent bond, and where a second water-insoluble ionic group of the water-insoluble ionic pair is coupled with the side chain of the hydrophobic polymer backbone by dynamic ion interaction.

[0119] Example 15. A composite material structure including: a polymer matrix including a hydrophobic polymer backbone, a side chain coupled to the hydrophobic polymer backbone, and a water-insoluble ionic group coupled with the side chain of the hydrophobic polymer backbone by dynamic ion bonds; and a filler material distributed in the polymer matrix, the filler material including nanoparticles or microparticles.

[0120] Example 16. The composite material structure of example 15, where the filler material is distributed in the polymer matrix in a raisin-in-bread structure.

[0121] Example 17. The composite material structure of example 15, where the filler material is distributed in the polymer matrix in a layered structure.

[0122] Example 18. The composite material structure of example 15, where the filler material is distributed in the polymer matrix in a 3D network structure.

[0123] Example 19. The composite material structure of any of examples 15 18, where the nanoparticles or microparticles include SiO2, CuO, graphene oxide, ZnO, Ti02, silicon, a-quartz, silicon oxynitride, ZnS, CdS.

[0124] Example 20. The composite material structure of any of examples 15 19, where the nanoparticles or microparticles includes nanoparticles of polydimethylsiloxane (PDMS), polyvinylidene fluoride (PVDF), or PVDF- hexafluoropropylene (PVDF-HFP) copolymer.

[0125] Example 21. A method for forming a self-healing surface, the method including: forming a polymeric material by coupling a water-insoluble ionic group with a side chain of a hydrophobic polymer backbone; mixing the polymeric material with additive nanoparticles or microparticles; and applying the polymeric material over an exposed surface of a substrate.

[0126] Example 22. The method of example 21, where applying the polymeric material over the exposed surface of the substrate includes plasma polymerization.

[0127] Example 23. The method of example 21 or 22, where applying the polymeric material over the exposed surface of the substrate includes spin coating.

[0128] Example 24. The method of any of examples 21- 23, where applying the polymeric material over the exposed surface of the substrate includes coating with a colloidal gel.

[0129] Example 25. The method of any of examples 21- 24, where applying the polymeric material over the exposed surface of the substrate includes spray coating.

[0130] Example 26. The method of any of examples 21 -25, where applying the polymeric material over the exposed surface of the substrate includes flow coating.

[0131] Example 27. The method of any of examples 21 - 26, where applying the polymeric material over the exposed surface of the substrate includes thermal spray coating.

[0132] Example 28. The method of any of examples 21- 27, where applying the polymeric material over the exposed surface of the substrate includes dip coating.

[0133] Example 29. The method of any of examples 21- 28, where mixing the polymeric material with additive nanoparticles or microparticles includes direct mixing or particle modification.

[0134] Example 30. The method of example 29, where the particle modification includes using binder, surfactant, or amphiphile.

[0135] Example 31. The method of example 30, where the binder, surfactant, or amphiphile includes polyvinyl alcohol, polyethylene glycol, epoxy resins, polysaccharides, sodium dodecyl sulfate, cetyltrimethylammonium bromide, Triton X-100, polysorbates, pluronic block copolymers, or stearic acid.

[0136] Example 32. The method of any of examples 21 -31, where the substrate includes a building material.

[0137] Example 33. The method of any of examples 21 -31, where the substrate is part of an electronic device housing or package.

[0138] Although the description has been described in detail, it should be understood that various changes, substitutions and alterations can be made without departing from the spirit and scope of this disclosure as defined by the appended claims. Moreover, the scope of the disclosure is not intended to be limited to the particular embodiments described herein, as one of ordinary skill in the art will readily appreciate from this disclosure that processes, machines, manufacture, compositions of matter, means, methods, or steps, presently existing or later to be developed, may perform substantially the same function or achieve substantially the same result as the corresponding embodiments described herein. Accordingly, the appended claims are intended to include within their scope such processes, machines, manufacture, compositions of matter, means, methods, or steps.

Claims

What is Claimed:

1. A polymeric material comprising: a hydrophobic polymer backbone; a side chain coupled to the hydrophobic polymer backbone; and a water-insoluble ionic pair coupled with the side chain of the hydrophobic polymer backbone, the water-insoluble ionic pair in combination with the hydrophobic polymer backbone being configured to be self-healing.

2. The polymeric material of claim 1, wherein the water-insoluble ionic pair in combination with the hydrophobic polymer backbone is configured to be self-healing with a presence of ambient water.

3. The polymeric material of claim 1 or 2, wherein the water-insoluble ionic pair in combination with the hydrophobic polymer backbone is configured to be self- healing without a presence of ambient water.

4. The polymeric material of any one of claims 1 3, wherein the water-insoluble ionic pair comprises carbon-halide bonds, nitrogen-halide bonds, or phosphorushalide bonds.

5. The polymeric material of any one of claims 1 4, further comprising functional fillers.

6. The polymeric material of claim 5, wherein the functional fillers comprise nanoparticles or microparticles of SiO2, CuO, graphene oxide, ZnO, TiO2, silicon, ct- quartz, silicon oxynitride, ZnS, or CdS.

7. The polymeric material of claim 5 or 6, wherein the functional fillers are distributed through the polymeric material in a raisin-in-bread structure.

8. The polymeric material of claim 5 or 6, wherein the functional fillers are distributed through the polymeric material in a layered structure.

9. The polymeric material of claim 5 or 6, wherein the functional fillers are distributed through the polymeric material in a 3D network structure.

10. The polymeric material of any one of claims 1 9, wherein the polymeric material has emissivity greater than 0.9 for radiation wavelengths in a range of 8 pm to 13 pm.

11. The polymeric material of any one of claims 1 10, wherein the polymeric material has an absorption multiplier lower than 0.05 for radiation wavelengths in a range of 0.4 pm to 2.5 pm.

12. The polymeric material of any one of claims 1 11, wherein the polymeric material has a self-healing efficiency greater than 60% at a temperature less than 60 °C under a pressure of 1 atmosphere in a time range of less than one week.

13. The polymeric material of any one of claims 1 12, wherein the hydrophobic polymer backbone is chosen from the group consisting of polydimethylsiloxane (PDMS), polyvinylidene fluoride (PVDF), and PVDF-hexafluoropropylene (PVDF- HFP) copolymer.

14. The polymer material of any one of claims 1- 13, wherein a first waterinsoluble ionic group of the water-insoluble ionic pair is coupled with the side chain of the hydrophobic polymer backbone by a covalent bond, and wherein a second water-insoluble ionic group of the water-insoluble ionic pair is coupled with the side chain of the hydrophobic polymer backbone by dynamic ion interaction.15- A composite material structure comprising: a polymer matrix comprising a hydrophobic polymer backbone, a side chain coupled to the hydrophobic polymer backbone, and a water-insoluble ionic group coupled with the side chain of the hydrophobic polymer backbone by dynamic ion bonds; and a filler material distributed in the polymer matrix, the filler material comprising nanoparticles or microparticles.

16. The composite material structure of claim 15, wherein the filler material is distributed in the polymer matrix in a raisin-in-bread structure.

17. The composite material structure of claim 15, wherein the filler material is distributed in the polymer matrix in a layered structure.

18. The composite material structure of claim 15, wherein the filler material is distributed in the polymer matrix in a 3D network structure.

19. The composite material structure of any of claims 15 18, wherein the nanoparticles or microparticles comprise SiO2, CuO, graphene oxide, ZnO, TiO2, silicon, a-quartz, silicon oxynitride, ZnS, CdS.

20. The composite material structure of any of claims 15-19, wherein the nanoparticles or microparticles comprises nanoparticles of polydimethylsiloxane (PDMS), polyvinylidene fluoride (PVDF), or PVDF-hexafluoropropylene (PVDF- HFP) copolymer.

21. A method for forming a self-healing surface, the method comprising: forming a polymeric material by coupling a water-insoluble ionic group with a side chain of a hydrophobic polymer backbone;mixing the polymeric material with additive nanoparticles or microparticles; and applying the polymeric material over an exposed surface of a substrate.

22. The method of claim 21, wherein applying the polymeric material over the exposed surface of the substrate comprises plasma polymerization.

23. The method of claim 21 or 22, wherein applying the polymeric material over the exposed surface of the substrate comprises spin coating.

24. The method of any of claims 21- 23, wherein applying the polymeric material over the exposed surface of the substrate comprises coating with a colloidal gel.

25. The method of any of claims 21 24, wherein applying the polymeric material over the exposed surface of the substrate comprises spray coating.

26. The method of any of claims 21 25, wherein applying the polymeric material over the exposed surface of the substrate comprises flow coating.

27. The method of any of claims 21 26, wherein applying the polymeric material over the exposed surface of the substrate comprises thermal spray coating.

28. The method of any of claims 21 27, wherein applying the polymeric material over the exposed surface of the substrate comprises dip coating.

29. The method of any of claims 21- 28, wherein mixing the polymeric material with additive nanoparticles or microparticles comprises direct mixing or particle modification.

30. The method of claim 29, wherein the particle modification comprises using binder, surfactant, or amphiphile.

31. The method of claim 30, wherein the binder, surfactant, or amphiphile comprises polyvinyl alcohol, polyethylene glycol, epoxy resins, polysaccharides, sodium dodecyl sulfate, cetyltrimethylammonium bromide, Triton X-100, polysorbates, pluronic block copolymers, or stearic acid.

32. The method of any of claims 21 31, wherein the substrate comprises a building material.

33. The method of any of claims 21 -31, wherein the substrate is part of an electronic device housing or package.

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