Polyurethane Composite Coatings Research Articles

Surface modified molybdenum disulfide nanosheets for corrosion resistance improvement on polyurethane coatings

Abstract Organic–inorganic hybrid coating has been applied on metallic corrosion protection effectively. Molybdenum disulfide (MoS2) nanosheets with graphene-like two-dimensional lamellar structure were an anticorrosion inorganic additive, rendering the organic coating better corrosion resistant. However, the aggregation and poor solubility are still current issues that should be addressed. Functionalization MoS2 nanosheets with surface modified by polydopamine (PDA) and silane coupling agent (KH560) were prepared in polyurethane (PU) composite coatings to obtain dense and intact multilayer network structure coatings for corrosion protection. KH560-PDA-MoS2/PU coating with crosslinked polymer network structure has a high impedance modulus, large contact angle, and strong hydrophobicity. The coating meets the national technical standards for salt spray testing and nitric acid (HNO3) titration testing, demonstrating excellent corrosion resistance.

Effects of Zr-based and Ni-based amorphous alloy powders on the wear resistance and corrosion behavior of polyurethane composite coatings on aluminum alloys

In this study, we present a new strategy for modifying polyurethane coatings to improve the surface performance of 6061 aluminum alloys, that is, Zr-based and Ni-based amorphous alloys were used as modified fillers. The addition of amorphous alloys resulted in alterations to the intermolecular forces among N-H bonds in the hard segments and the H-bond strength of CO bonds in the urea groups. The introduction of amorphous particles disordered the original arrangement of the fillers and gave rise to near-ring structures, which typically has a positive effect on the overall performance of the coatings. Under the synergistic effect of amorphous alloy properties and H-bond strength, hardness and wear resistance increased with increasing amorphous content. The coatings exhibit a certain degree of stealth performance, and the addition of amorphous alloys substantially improves the corrosion resistance of the coatings. Among the polyurethane/amorphous alloy composite coatings, the one containing 50 vol% Zr-based amorphous alloy has the best overall performance. Compared to previous researches, we pioneered the utilization of outstanding properties of Zr-based and Ni-based amorphous alloys to improve polyurethane coatings. This novel composite coating has great potential to be used as a corrosion-resistant coating and to be combined with good mechanical properties.

Mechanical and UV protection performances of polylactic acid spunlace nonwoven fabrics coated by eco-friendly lignin/water-borne polyurethane composite coatings

Lignin as a biopolymer, has drawn much attention owing to its renewable nature, biodegradability, easy availability, and excellent stability. Water-borne polyurethane (WPU)-based coatings have been contributing to sustainable and eco-friendly practices offer a straightforward avenue for the value-added utilization of lignin. With the alarming rise in death rates attributed to skin diseases due to ultraviolet (UV) radiation damage, researchers have been actively searching for sustainable coating processes that enhance the UV protective capabilities of fabrics. In this paper, a facile strategy was reported for fabricating an environment friendly, mechanically durable, and UV protective biodegradable polylactic acid (PLA) spunlace nonwoven fabrics (SNFs) using lignin/WPU composite coatings. Lignin/WPU coating pastes were prepared using five different recipes including different lignin concentrations (0.5, 1.0, 1.5, and 2.0 wt.%) and coated on PLA SNFs via an applicator and thermally cured. Mechanical properties (e.g. tensile strength and abrasion resistance) and UV protection factor (UPF) values of fabrics were investigated. The coating films were characterized by Fourier Transform-Infrared (FTIR) spectroscopy and scanning electron microscopy (SEM) analysis. Lignin/WPU coated SNFs showed excellent UV protection performance and UPF values were obtained above 100 for all formulations. Lignin/WPU coatings provided an improving effect on the tensile strength and abrasion resistance performances of coated SNFs compared to uncoated SNFs. This work provides a simple and efficient strategy for preparing environmentally friendly lignin/WPU coatings, which are promising for application in the textile industry.

Synthesis of Silanated Coconut Oil-Based Waterborne Polyurethane Coating for Corrosion Protection

In this study, an eco-friendly coconut oil-based polyol blend was synthesized for bio-based waterborne polyurethane (WBPU) and WBPU-silane composite coatings. It was demonstrated that an increase in silane content incorporated into the WBPU matrix significantly enhanced the corrosion protection of WBPU coatings. Results also show a fourfold increase in the adhesion strength of WBPU-silane composite coatings as compared to that of bare WBPU coatings. Further, the water contact angle revealed that hydrophobic properties increase as the silane content incorporated into the WBPU matrix increases. This work provides a novel route for enhanced corrosion protection utilizing a bio-based polyol blend.

Facile fabrication of robust and universal UV‐curable polyurethane composite coatings with antibacterial properties

AbstractThe colonization of bacteria and biofilm formation on the surface of medical devices is one of the main causes of nosocomial infections. The development of antimicrobial functional materials with robust and universal properties has been a hot research topic in this field. In this paper, a novel type of polyurethane composite coating was developed by a complementary combination of polyurethane and antibacterial agents. A photocurable anionic waterborne polyurethane was first synthesized using polycarbonate diol (PCDL), isophorone diisocyanate (IPDI), 2,2‐dimethylolpropionic acid (DMPA), and hydroxyethyl acrylate (HEA) as raw materials. Polyurethane composite coatings were prepared by associating cationic antibacterial agents with polyurethane molecules through electrostatic assembly, hydrophobic interactions and hydrogen bonding, and the mechanical properties, adhesion, and antibacterial properties of the polyurethane composite coatings were studied. The results showed that the polyurethane composite coatings had good mechanical properties, and the introduction of cationic antibacterial agents significantly improved the antibacterial ability of the polyurethane material. The antibacterial efficiency of polyurethane against E. coli and S. aureus reached 99% and exhibited durable antibacterial performance as well. Moreover, the polyurethane composite coatings showed excellent adhesion to a variety of substrates, demonstrating their potential application as a universal antimicrobial coating in the medical field.Highlights Construction of polyurethane composite with electrostatic self‐assembly method. Surface coating technology with fast curing, robustness, and universality. Excellent mechanical and antibacterial properties of composite coatings.

Synergistic effect of silica aerogel and titanium dioxide in porous polyurethane composite coating with enhanced passive radiative cooling performance

Passive daytime radiative cooling is a promising technology that can mitigate the increasing issues of global warming and urban heat island effects. In this work, a series of porous polyurethane (PPU) composite coatings containing silica aerogel (SA) and/or titanium dioxide (T) were prepared though a wet phase inversion method. The effects of the filler types on relevant properties of composite coatings, such as pore microstructure, radiative cooling, mechanical, and hydrophobic performances, were systematically investigated. The typical PPU-SA10@T10 composite coating showed an interleaving porous structure, and the incorporated SA and T fillers were uniformly stacked in the pore cavities. Taking advantages of the strong light-back scattering and molecular oscillation functions, the solar reflectance, thermal emittance in the atmospheric transparency window, and the net cooling power of the PPU-SA10@T10 coating reached 0.917, 0.973, and 87.8 W/m2, respectively, which results in a sub-ambient cooling of 7.8 °C at midday under a solar irradiance of ∼640 W/m2. Moreover, the PPU-SA10@T10 coating possessed well balanced mechanical properties and superior hydrophobicity (water contact angle was 121.7°). The present work provides a viable way for developing radiative cooling coating with desirable mechanical properties and water-repellency.

Waterborne polyurethane composite coatings as UV-light converter and directional infrared light barrier for light and heat management in greenhouse

Light and heat management in greenhouses are important for crops yield and quality. Here, we created waterborne polyurethane (WPU) composite coatings for greenhouse films, which can act both as ultraviolet (UV) light down-conversion and directional infrared light barrier for the light and temperature conditions in pepper greenhouses. Rare-earth organic complexes (REOC) that can convert UV light to red light were mixed with WPU by ball-milling. The REOC nanoparticles presented good dispersion in WPU coatings, which were determined by atomic force microscopy, and the coating with 1 wt% REOC still remained comparably high transparency. The luminescence properties were increased with REOC loadings. The coatings with REOC showed lower infrared (IR) light transmittance and higher IR light reflectance than those of the pristine film and WPU coatings. The preferable location of the composite coatings on inner side of films acted as IR light barrier and facilitated the maintenance of heat inside the greenhouses, increasing the temperature. Simulation was performed to testify the temperature increase using IR barrier covered layer. Small and big greenhouses with different films were built and the temperatures were recorded. The results show that the film containing REOC increase the temperature in the greenhouses by >2 °C compared to traditional agricultural films. Finally, due to light conversion and IR light barrier, the yields of green peppers can be increased by 35 %. The mass of single fruits can also be increased by 8 g.

Antifouling and anticorrosion function of repeatable self-healing polyurethane composite inspired by the self-healing principle of cartilage tissue

Micro-cracking caused by the impact of gravel in the ocean is an important factor affecting the longevity of the integrated antifouling and anticorrosion coating. Inspired by the animal cartilage tissue, a series of polyurethane composite coatings (MPU-FrGO) with repeatable self-healing functions were successfully prepared. MPU-FrGO are endowed with excellent antifouling and anticorrosion ability because they contain functional reduced graphene oxide (FrGO) and 2-methyl 4-isothiazoline 3-ketone (MIT). As animal cartilage tissues, two-dimensional structure of FrGO forms hydrogen bond crosslinking and chemical crosslinking with polyurethane in MPU-FrGO. The super strong spatial network endows MPU-FrGO3 (the amount of FrGO added is 1 wt%) with excellent mechanical properties and strong self-healing ability. Its stress (35.6 MPa) and strain (861%) is far more than that of PU-FrGO0 (27.2 MPa and 762%). MPU-FrGO3 showed exceptional self-healing performance, and the self-healing efficiency could reach 91% (91% of initial stress) after 15 min of NIR irradiation; the self-healing efficiency of five cycles can reach more than 83% (83% of initial stress). The |Z|0.01Hz of MPU-FrGO3 can still maintain 3.34 × 108 Ω·cm2 after immersed in 3.5 wt% NaCl for 15 days because of the excellent barrier performance of FrGO. Owing to the excellent antibacterial and anti-algal functions of FrGO and MIT, the antibacterial ability and algae inhibition coverage ability of MPU-FrGO3 were 99.5% and 97.1%, respectively. The work provides a heuristic perspective for the design of polymer materials with anticorrosion, antifouling, and self-healing.

Interpenetrating network structure design and corrosion resistance of high‐performance waterborne polyurethane coating modified by epoxy resin and functionalized graphene oxide

AbstractTo obtain graphene oxide (GO) derivatives‐based waterborne polyurethane (WPU) composite coatings with high anti‐corrosion performance, microstructure, dispersion and interfacial adhesion of the coatings are key factors to consider. In this study, the waterborne polyurethane modified by epoxy resin (WEPU) and graphene oxide (GO) derivatives was synthesized by copolymerization, and its synergistic effect on the anti‐corrosion properties of waterborne polyurethane (WPU) coating was investigated. For this purpose, the isophorone diisocyanate (IPDI) was grafted to the surface of GO. Then, the functionalized GO (iGO) was uniformly dispersed in the WEPU emulsions by a prepolymer method, which was attributed to strong interaction between iGO and WEPU, as proved by FTIR spectra and SEM images. The deterioration process of WEPU and iGO‐WEPU coatings during the long‐term immersion in 3.5 wt% NaCl solution was investigated by electrochemical impedance spectroscopy (EIS). The results indicated that the introduction of well dispersed iGO nanosheets into WEPU system enhanced the corrosion protection performance to substrate. Significantly, for the 0.9 wt% iGO nanosheets reinforced WEPU composite films, the contact angle value of iGO‐WEPU composite films (94.7°) reaches the highest in comparison with that of pure WEPU film (88°), thus remarkably improving the water barrier property of iGO‐WEPU coating.

Surface morphology properties and antifouling activity of Bi2WO6/boron-grafted polyurethane composite coatings realized via multiple synergy

An inorganic–organic composite coating is an effective way to solve the issue of marine organism attachment and realize multi-element synergistic antifouling. Herein, Bi2WO6/boron-grafted polyurethane composite coatings (BWOB) composed of Bi2WO6 with three morphologies (nanosheet, flower and microsphere) and boron-grafted polyurethane (ITB) were successfully synthesized to achieve high-efficiency antifouling. Bi2WO6 nanoparticles were evenly distributed on the surface and inside the ITB to form micro/nanostructures. In the composite coatings doped with flower-shaped Bi2WO6, BWOB-5 showed excellent antibacterial and antidiatom adhesion properties, achieving 95.43% and 98.38% against Escherichia coli and Staphylococcus aureus, respectively, and 98.62% against Nitzschia closterium. In addition, the micro/nanostructure on the surface, the stable production of hydroxyl radicals (·OH) and superoxide radicals (·O2–) during photocatalysis, and the antifouling functional groups of the resin matrix in the BWOB composite coatings were all conducive to photocatalytic antifouling activity. More importantly, BWOB coatings exhibited excellent environmentally friendly properties. Therefore, BWOB coatings are expected to have potential application value in the field of photocatalytic sterilization and antifouling.

Preparation of Palygorskite hybrid iron oxide red pigment and its application in waterborne polyurethane composite coatings and ceramics

Palygorskite (Pal) is a kind of magnesium aluminum silicate clay mineral with a one-dimensional rod and layer chain structure. Herein, Pal hybrid iron oxide red pigment (Pal/α-Fe2O3) was prepared by the grinding method. Pal acted as a matrix to fix α-Fe2O3 particles and influenced the performances of composite pigments by changing the particle size and distribution of α-Fe2O3. The color difference analysis showed that the color performances of composite pigments were closely related to the ratio of Pal to α-Fe2O3. Compared with the original red iron oxide pigment, the tinting strength of the composite pigment was increased by about 15%. When Pal/α-Fe2O3 was used as the red pigment for coating, it had good storage stability for waterborne coating and improved its adhesion and corrosion resistance. Pal/α-Fe2O3 composite pigments had excellent high-temperature resistance, which could increase the calcination temperature of ceramic pigments and would be beneficial for the ceramic industry. The synthetic method of Pal/α-Fe2O3 composite pigment was simple, low-cost, and environmentally friendly, and could be applied to large-scale industrial production.

Anti-corrosion and self-healing behaviors of waterborne polyurethane composite coatings enhanced via chitosan-modified graphene oxide and phosphate intercalated hydrotalcite

Surface coating technology has been widely used in anti-corrosion field. A well-stacked layered material offers a strong barrier and labyrinth effect to improve the corrosion resistance of organic coatings. However, as a typical layered material, the hydrotalcite dispersion is unstable and prone to delamination. Herein, a strategy for grafting chitosan on graphene oxide and then electrostatic self-assembling with hydrotalcite was proposed. The graphene oxide was modified with chitosan to enhance its barrier performance and corrosion resistance, and then hydrotalcite was coated on the surface of graphene oxide through electrostatic self-assembly to improve the dispersion of hydrotalcite and the interfacial compatibility with resin. At the same time, PO43− between the hydrotalcite layers provides the coating with self-healing ability. Chitosan, graphene oxide and hydrotalcite nano-hybrid materials were introduced into waterborne polyurethane, and a corrosion-resistant coating with a thickness of about 40 μm was prepared. Excellent anti-corrosion behaviors were obtained through the synergistic effect of graphene oxide and hydrotalcite stacking due to the formation of a dense protective layer and the self-healing characteristics of chitosan and phosphate ions. This new type of waterborne polyurethane composite coatings offers broad application prospects in the research and development of high-performance self-healing anti-corrosive coatings.

SiC-enhanced polyurethane composite coatings with excellent anti-fouling, mechanical, thermal, chemical properties on various substrates

Polyurethane (PU) coatings with excellent corrosion resistance and wear resistance are regularly used in furniture coating, metal corrosion protection, electronic device protection and other fields. However, due to the shortcomings of low hydrophobicity and thermal stability, PU coatings are limited to be widely used as waterproof and breathable materials. This is expected to be improved by nanoparticles with high thermal conductivity and robust properties, such as silicon carbide (SiC). Here, the SiC-enhanced PU composite coatings modified by perfluorooctyltriethoxysilane (PFOTS) were successfully fabricated by spraying. The dispersion of SiC after chemical grafting modification of PFOTS in PU was significantly improved. The hard SiC particles provided a special micro-nano structure on the surface of the PU coating, altering the wettability of the coating from hydrophilic to superhydrophobic. The 125 wt% F-SiC/PU composite coating showed the best superhydrophobic properties with good wear resistance, anti-stripping ability, thermal stability, salt spray resistance and acid/base resistance, which depends on the uniform dispersion of SiC with high hardness and high thermal conductivity in the PU coating. The 125 wt% F-SiC/PU composite coating can present superhydrophobic properties on different substrates, such as aluminum alloy, ceramic, plastic sheet and filter paper, and have certain anti-fouling properties. This research provides a new strategy for the development of wear-resistant and anti-fouling PU superhydrophobic coatings.

Highly effective anti-corrosion composite coatings enhanced by non-covalent functionalized boron nitride nanosheets via a facile latex approach

Boron nitride nanosheets (BNNSs)/polymer composite coatings with highly effective corrosion resistance have promising applications in metal surface protection. However, BNNSs tend to aggregate in waterborne polymer matrix, which degrades anticorrosion. Herein, a facile and effective method was developed to fabricate a stable latex containing non-covalently modified BNNSs through in situ polymerization of styrene in emulsion system, and waterborne polyurethane (WPU) composite coatings were sequentially constructed for the purpose of corrosion protection via latex blending. The developed composite coating (BNNSs@PS/WPU) exhibited a significantly improved impedance by 4 orders of magnitude after 28 days of immersion compared with pure WPU coating. Such outstanding anti-corrosion properties can be ascribed to the comprehensive action of BNNSs@PS composite latex, of which the PS microspheres can not only effectively prevent BNNSs from coalesce, but also act synergically with BNNSs that effectively retard the permeation of corrosive medium to the metal surface.

Research Status of Graphene Polyurethane Composite Coating

Graphene material has a variety of excellent properties and applications in energy storage, biomaterials, photoelectric devices, and other fields. With the progress of nanotechnology, graphene nanomaterials have shown their advantages in the field of new nano-corrosion coatings with their high barrier structure. In addition, polyurethane is also widely used in the field of anti-corrosion coatings due to its excellent chemical resistance, mechanical properties, and weathering resistance. The preparation of composite coatings by combining graphene nanomaterials with traditional polyurethane (PU) coatings has opened up a new way for the research and development of new anticorrotic coatings. In this paper, graphene polyurethane composite coating was first used as the research object, and the mechanism of graphene material in the new composite coating was analyzed. Then, graphene oxide (GO), a commonly used precursor material, was used as an entry point for a detailed study of the properties of GO materials and the advantages and disadvantages of its application in composites, and two types of modifications, covalent and non-covalent, were analyzed. In addition, the preparation methods and processes of graphene polyurethane composite coatings were summarized. Finally, the future research directions and research focus of GO were prospected.

Stretchable and self-healing polyurethane coating with synergistic anticorrosion effect for the corrosion protection of stainless steels

Introduction of inorganic fillers into organic coatings is significant for enhancing mechanical properties and corrosion protection. Herein, we utilized the barrier function of the laminar structure (MXene, Ti3C2) and the inhibition property of the corrosion inhibitor (CeO2) to prepare a MXene/CeO2 polyurethane composite coatings and investigated the corrosion protection performance in 3.5 wt% NaCl solution. Benefiting from the “labyrinth effect” of MXene and the inhibition effect of CeO2, the composite coating exhibits excellent corrosion resistance. What's more, we introduced the DA bonds into the coating to endow it with self-healing property. The results demonstrated that the obtained composite coating could achieve efficient self-healing behavior under sunlight, and its mechanical properties and anti-corrosion properties were basically unaffected after self-healing. Our strategy presents a new approach to protection of coating for metal substrates and provides the basis for a multi-mechanism synergistic approach to corrosion protection.

Experimental Investigations of AlMg3 Components with Polyurethane and Graphene Oxide Nanosheets Composite Coatings, after Accelerated UV-Aging.

The use of graphene (Gr) and its derivates graphene oxide (GO) showed that these materials are good candidates to enhance the properties of polyurethane (PU) coatings, especially the anticorrosion ones since graphene absorbs most of the light and provides hydrophobicity for repelling water. An important aspect of these multifunctional materials is that all these improvements can be realized even at very low filler loadings in the polymer matrix. In this work, an ultrasound cavitation technique was used for the proper dispersion of GO nanosheets (GON) in polyurethane (PU) resin to obtain a composite coating to protect the AlMg3 substrate. The addition of GON considerably improved the physical properties of coatings, as demonstrated by electrochemical impedance spectroscopy (EIS) analysis, promising improved anticorrosion performance after accelerated UV-ageing. Computational methods and Differential Scanning Calorimetry (DSC) measurements showed that GON facilitates the formation of additional bonds and stabilizes the PU structures during the ultraviolet (UV) exposure and aggressive attack of corrosive species. Limiting oxygen index (LOI) data reveal a slow burning behaviour of PU-GON coatings during UV exposure, which is better than PU alone.

Design on the corrosion protection of eco-friendly and multifunctional polyhedral oligomeric silsesquioxane functionalized graphene oxide reinforced waterborne polyurethane

This paper explored that the novel waterborne polyurethane (WPU) composite coatings with superior corrosion protection performance was fabricated via intercalating functionalized graphene oxide (GO). The eco-friendly and superhydrophobic aminoethyl aminopropyl isobutyl polyhedral oligomeric silsesquioxane (POSS-NH-NH2) was applied to modify GO via facile one-step chemical grafting. Several analyses such as FT-IR, XRD, Raman, and SEM were performed to verify the successful graft of POSS-NH-NH2 into the GO. Sequentially, the WPU and WPU composite coatings containing GO and functional graphene oxide (PNNG) nanoparticles were prepared and applied on Q235 steel with a thickness of 55 ± 5 µm. The corrosion protection performance of coatings was investigated by electrochemical impedance spectroscopy and potentiodynamic polarization. The results highlighted that well-dispersed and hydrophobic PNNG nanoparticle remarkably enhanced the corrosion protection performance of WPU. In detail, the protection efficiency of WPU composite coatings with 0.1 wt% PNNG reached 99.79% relative to pure WPU. After 21 days’ immersions in 3.5 wt% NaCl aqueous solution, the ǀZ|f=0.01Hz of WPU decreased to 1.96 × 105 Ω cm2 from 1.52 × 107 Ω cm2. However, the ǀZ|f=0.01Hz of WPU with 0.1 wt% PNNG was 1.48 × 108 Ω cm2 after 180 days’ immersions, which was still about 3 orders of magnitude higher than that of WPU.

Fabrication of high transparent, mechanical strong, and flame retardant waterborne polyurethane composites by incorporating phosphorus‐silicon functionalized cellulose nanocrystals

AbstractTo manufacture transparent waterborne polyurethane composite coatings that possess desirable mechanical and flame retardancy properties is still a challenge. Herein, we first synthesized phosphorus‐silicon functionalized cellulose nanocrystals (FCNC) filler, and further introduced it into waterborne polyurethane (WPU) matrix to prepare composite. The phosphorus‐silicon‐containing components were grafted covalently on the surface of FCNC, and the FCNC showed good dispersion level in water and WPU matrix. Moreover, the inserted FCNC could not only maintain the high transparency of WPU‐FCNCs composites, but also remarkably enhancing the mechanical and flame retardancy performances. Noticeably, the WPU‐FCNC3 composite containing 3 wt% of FCNC showed balanced mechanical (σb = 16.7 MPa, εb = 557.5%), limiting oxygen index (22.9%), and a UL‐94 rating of V‐2 among prepared films. Additionally, WPU‐FCNC3 composite exhibited significantly reductions in heat release during combustion, and also showed a high transmittance of 92.2%. The present research supplies promising way for developing transparent, toughness, and flame retardant composite coatings.

Effects of Al-based alloy powders on the mechanical behavior, corrosion resistance and infrared emissivity of polyurethane composite coatings

Aluminum (Al)-based amorphous alloys (hereinafter abbreviated as AAA) with good mechanical and anti-corrosion properties are ideal fillers for modified organic coatings. A novel polyurethane (PU)/Al/AAA composite coating was prepared by adding Al-based alloy powders, which were composed of Al and AAA powders. The effects of Al or AAA powder concentration on the mechanical behavior, corrosion resistance and infrared (IR) emissivity of PU/Al/AAA coatings were systematically investigated and compared with those of PU/Al coatings. The AAA particles surrounded by Al flakes form annular structures in the polymer matrix. With the increase of AAA powder concentration, the hardness, IR emissivity, wear resistance and anti-corrosion of the PU/Al/AAA coating are increased, whereas the adhesion strength is slightly decreased. Moreover, excess AAA powder has a negative effect on wear and corrosion resistance of the coating. The optimal AAA powder proportion in the filler was found to be 57 wt%, resulting in a composite coating with good mechanical and anti-corrosion properties as well as low IR emissivity. The AAA powder developed by this work can serve as a good modified filler for high-performance PU coatings.