Pub Date : 2024-08-26DOI: 10.1016/j.porgcoat.2024.108753
The double-walled microcapsules triggered under the crack/Cl− condition were prepared by using isocyanate and 1,6-diaminohexane respectively as the internal and external core material, and polyurea as the wall material. During the synthesis process, lead sulfate was added to the wall material to trap chloride ions. The morphology and dispersion of the microcapsules embedded in the epoxy composite were characterized, using the scanning electron microscope (SEM) and super depth of field microscope. Self-healing coatings containing 0.0 wt%, 3.0 wt%, 5.0 wt%, and 8.0 wt% of composite double-walled microcapsules were subjected to tensile tests. The digital speckle correlation method (DSCM) and pull-out test were applied to analyze the mechanical properties and crack-triggering principle of the coating. The toughening effect and self-healing behavior of the epoxy resin with varying dosages of microcapsules were studied. The self-healing efficiency and mechanism of the composite coating were obtained during the process of stretching, crack expansion, and micro-capsule triggering.
{"title":"Crack/Cl− - triggered design and tensile self-healing mechanism of epoxy coatings on offshore steel bars","authors":"","doi":"10.1016/j.porgcoat.2024.108753","DOIUrl":"10.1016/j.porgcoat.2024.108753","url":null,"abstract":"<div><p>The double-walled microcapsules triggered under the crack/Cl<sup>−</sup> condition were prepared by using isocyanate and 1,6-diaminohexane respectively as the internal and external core material, and polyurea as the wall material. During the synthesis process, lead sulfate was added to the wall material to trap chloride ions. The morphology and dispersion of the microcapsules embedded in the epoxy composite were characterized, using the scanning electron microscope (SEM) and super depth of field microscope. Self-healing coatings containing 0.0 wt%, 3.0 wt%, 5.0 wt%, and 8.0 wt% of composite double-walled microcapsules were subjected to tensile tests. The digital speckle correlation method (DSCM) and pull-out test were applied to analyze the mechanical properties and crack-triggering principle of the coating. The toughening effect and self-healing behavior of the epoxy resin with varying dosages of microcapsules were studied. The self-healing efficiency and mechanism of the composite coating were obtained during the process of stretching, crack expansion, and micro-capsule triggering.</p></div>","PeriodicalId":20834,"journal":{"name":"Progress in Organic Coatings","volume":null,"pages":null},"PeriodicalIF":6.5,"publicationDate":"2024-08-26","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142077265","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":2,"RegionCategory":"材料科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Pub Date : 2024-08-24DOI: 10.1016/j.porgcoat.2024.108751
Glass is a transparent and geometrically ordered element in architecture. Glass bonding can be classified into adhesive, layered, and mechanical categories. One of the best bonding materials for glass applications is adhesive. The preparation and investigation of Ultraviolet (UV)-curable composites for glass-to-glass bonding is the goal of this research. The investigation focused on the effect of raw material type and weight percentage on mechanical properties. Epoxy acrylate resin was employed as an oligomer in this study. Trimethylolpropane triacrylate (TMPTA), tripropyleneglycol triacrylate (TPGDA), and pentaerythritol tetraacrylate (PETA) were used as monomers. As photoinitiators, were used bis (2,4,6 trimethylbenzoyl)-phenylphosphine oxide, hydroxycyclohexyl phenylketone, and 2,4,6-trimethylbenzoyl diphenyl phosphineoxide. Benzophenone, acrylic acid, nano silica, and trimethoxysilylpropyl methacrylate (TMSPMA) were used as the additives. The mechanical properties of the samples were studied using compressive and shear tests. The degree of conversion (DC) was obtained using Fourier transform infrared spectroscopy (FTIR). The mechanical behavior of the samples were measured as a function of temperature using dynamic mechanical thermal analysis (DMTA); and the distribution of nanoparticles was examined using scanning electron microscopy (SEM). The results showed that the sample containing 4 wt% nano silica, which also contained 24 wt% PETA and 7 wt% TMSPMA, has the best mechanical properties with 0.42 and 0.63 MPa compressive and shear strength, respectively. In the FTIR, was observed an increase of nano silica from the lowest (1 wt%) to the highest amount (5 wt%), the DC current decreased by 11 %. In the DMTA analysis, it was observed that an increase of nano silica from 1 to 5 wt%, the storage modulus increased by 41 %. The highest loss modulus and loss temperature were related to the samples containing 1 and 2 wt% nano silica with 221 MPa and 113.8 °C. Finally, the best distribution of nanoparticles was observed in the sample containing 1 wt% nano silica. In the SEM images, agglomeration of nanoparticles was seen in the sample containing 5 wt% nano silica.
{"title":"Preparation and characterization of UV-curable composite containing nano silica for glass-to-glass bonding","authors":"","doi":"10.1016/j.porgcoat.2024.108751","DOIUrl":"10.1016/j.porgcoat.2024.108751","url":null,"abstract":"<div><p>Glass is a transparent and geometrically ordered element in architecture. Glass bonding can be classified into adhesive, layered, and mechanical categories. One of the best bonding materials for glass applications is adhesive. The preparation and investigation of Ultraviolet (UV)-curable composites for glass-to-glass bonding is the goal of this research. The investigation focused on the effect of raw material type and weight percentage on mechanical properties. Epoxy acrylate resin was employed as an oligomer in this study. Trimethylolpropane triacrylate (TMPTA), tripropyleneglycol triacrylate (TPGDA), and pentaerythritol tetraacrylate (PETA) were used as monomers. As photoinitiators, were used bis (2,4,6 trimethylbenzoyl)-phenylphosphine oxide, hydroxycyclohexyl phenylketone, and 2,4,6-trimethylbenzoyl diphenyl phosphineoxide. Benzophenone, acrylic acid, nano silica, and trimethoxysilylpropyl methacrylate (TMSPMA) were used as the additives. The mechanical properties of the samples were studied using compressive and shear tests. The degree of conversion (DC) was obtained using Fourier transform infrared spectroscopy (FTIR). The mechanical behavior of the samples were measured as a function of temperature using dynamic mechanical thermal analysis (DMTA); and the distribution of nanoparticles was examined using scanning electron microscopy (SEM). The results showed that the sample containing 4 wt% nano silica, which also contained 24 wt% PETA and 7 wt% TMSPMA, has the best mechanical properties with 0.42 and 0.63 MPa compressive and shear strength, respectively. In the FTIR, was observed an increase of nano silica from the lowest (1 wt%) to the highest amount (5 wt%), the DC current decreased by 11 %. In the DMTA analysis, it was observed that an increase of nano silica from 1 to 5 wt%, the storage modulus increased by 41 %. The highest loss modulus and loss temperature were related to the samples containing 1 and 2 wt% nano silica with 221 MPa and 113.8 °C. Finally, the best distribution of nanoparticles was observed in the sample containing 1 wt% nano silica. In the SEM images, agglomeration of nanoparticles was seen in the sample containing 5 wt% nano silica.</p></div>","PeriodicalId":20834,"journal":{"name":"Progress in Organic Coatings","volume":null,"pages":null},"PeriodicalIF":6.5,"publicationDate":"2024-08-24","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142058316","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":2,"RegionCategory":"材料科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Pub Date : 2024-08-24DOI: 10.1016/j.porgcoat.2024.108750
With the continuous development of electronic products, polymers with EM shielding have received widespread attention. In this study, Fe3O4@RGO was prepared by the hydrothermal synthesis method, which solved the problems of Fe3O4 precipitation and RGO stacking. Using it as a precursor, Fe3O4@RGO/PAM conductive hydrogel was prepared. The research shows that the conductivity of this hydrogel reaches 16.2 S/m at a thickness of 0.3 cm, and the maximum EMI SE is 27.1 dB. Among them, RGO can form a conductive framework, and Fe3O4 can optimize the impedance matching and provide additional magnetic loss. The combined effect of the two makes the hydrogel have excellent EMI SE. In addition, PAM-based hydrogels have good thermal stability, crystallinity, water content, and mechanical properties.
{"title":"RGO loaded Fe3O4 strategy to construct high toughness PAM hydrogel for electromagnetic shielding","authors":"","doi":"10.1016/j.porgcoat.2024.108750","DOIUrl":"10.1016/j.porgcoat.2024.108750","url":null,"abstract":"<div><p>With the continuous development of electronic products, polymers with EM shielding have received widespread attention. In this study, Fe<sub>3</sub>O<sub>4</sub>@RGO was prepared by the hydrothermal synthesis method, which solved the problems of Fe<sub>3</sub>O<sub>4</sub> precipitation and RGO stacking. Using it as a precursor, Fe<sub>3</sub>O<sub>4</sub>@RGO/PAM conductive hydrogel was prepared. The research shows that the conductivity of this hydrogel reaches 16.2 S/m at a thickness of 0.3 cm, and the maximum EMI SE is 27.1 dB. Among them, RGO can form a conductive framework, and Fe<sub>3</sub>O<sub>4</sub> can optimize the impedance matching and provide additional magnetic loss. The combined effect of the two makes the hydrogel have excellent EMI SE. In addition, PAM-based hydrogels have good thermal stability, crystallinity, water content, and mechanical properties.</p></div>","PeriodicalId":20834,"journal":{"name":"Progress in Organic Coatings","volume":null,"pages":null},"PeriodicalIF":6.5,"publicationDate":"2024-08-24","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142058315","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":2,"RegionCategory":"材料科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Pub Date : 2024-08-24DOI: 10.1016/j.porgcoat.2024.108766
The flame-retardant properties of expanded polystyrene (EPS) foam were enhanced by constructing a flame-retardant coating on its surface using melamine modified urea-formaldehyde resin (MUF), H3BO3, and Al(OH)3 as raw materials. A coating consisting of an equal proportion of H3BO3 and Al(OH)3 demonstrated superior mechanical properties, flame-retardant properties, and smoke suppression ability. Additionally, this coating increased the compressive strength of EPS material by 43.30 %, raised the carbon residue from 0.14 % to 32.4 %, elevated the limiting oxygen index to 37.4 %, and achieved a vertical combustion rating of V-0 according to UL-94 standards. These improvements were accompanied by a reduction in peak heat release rate by 59.36 %, total smoke production by 51.99 %, maximum smoke density by 80.13 %, and smoke density rating by 89.52 %. Furthermore, the coated material exhibited satisfactory water resistance, thermal insulation, and transparency. Simulation results show that the MUF/H3BO3/Al(OH)3 coating system generated various metal and non-metal compounds during combustion along with NOx, COx, and H2O gases. The beneficial flame-retardant effect of the coating can be attributed to the hybrid flame-retardant effect of H3BO3 and Al(OH)3 in both the gas and condensed phases.
{"title":"Highly effective flame-retardant coatings consisting of urea-formaldehyde resin/aluminium hydroxide/boric acid for polystyrene foam: Properties and mechanisms investigation","authors":"","doi":"10.1016/j.porgcoat.2024.108766","DOIUrl":"10.1016/j.porgcoat.2024.108766","url":null,"abstract":"<div><p>The flame-retardant properties of expanded polystyrene (EPS) foam were enhanced by constructing a flame-retardant coating on its surface using melamine modified urea-formaldehyde resin (MUF), H<sub>3</sub>BO<sub>3</sub>, and Al(OH)<sub>3</sub> as raw materials. A coating consisting of an equal proportion of H<sub>3</sub>BO<sub>3</sub> and Al(OH)<sub>3</sub> demonstrated superior mechanical properties, flame-retardant properties, and smoke suppression ability. Additionally, this coating increased the compressive strength of EPS material by 43.30 %, raised the carbon residue from 0.14 % to 32.4 %, elevated the limiting oxygen index to 37.4 %, and achieved a vertical combustion rating of V-0 according to UL-94 standards. These improvements were accompanied by a reduction in peak heat release rate by 59.36 %, total smoke production by 51.99 %, maximum smoke density by 80.13 %, and smoke density rating by 89.52 %. Furthermore, the coated material exhibited satisfactory water resistance, thermal insulation, and transparency. Simulation results show that the MUF/H<sub>3</sub>BO<sub>3</sub>/Al(OH)<sub>3</sub> coating system generated various metal and non-metal compounds during combustion along with NO<sub>x</sub>, CO<sub>x</sub>, and H<sub>2</sub>O gases. The beneficial flame-retardant effect of the coating can be attributed to the hybrid flame-retardant effect of H<sub>3</sub>BO<sub>3</sub> and Al(OH)<sub>3</sub> in both the gas and condensed phases.</p></div>","PeriodicalId":20834,"journal":{"name":"Progress in Organic Coatings","volume":null,"pages":null},"PeriodicalIF":6.5,"publicationDate":"2024-08-24","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142048460","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":2,"RegionCategory":"材料科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Pub Date : 2024-08-24DOI: 10.1016/j.porgcoat.2024.108749
Silicone coatings with anti-smudge, anti-fingerprint, abrasion resistance, and ultraviolet (UV) resistance properties are increasingly demanded for touch screens as the development of artificial intelligence and human-computer interaction interfaces. Herein, a transparent, robust, and self-cleaning silicone coating was developed by incorporating cage-like structures and long carbon chains into a 3D cross-linked network via the rational combination of polymethylhydrosiloxane (PMHS), PSS-Octavinyl substituted (VPOSS), lauryl acrylate (LA), and 1,2-epoxy-4-vinylcyclohexane (EVCH) through hydrosilylation reaction with the presence of Karstedt catalysts. After introducing sealed diphenyliodonium phosphate (I-200), the silicone coating (PVLE-I-200) demonstrated excellent pencil hardness, anti-smudge, and abrasion resistance, and its average transmittance of visible light reached about 92 %. Owing to the low surface energy carbon chains, the coating showed amphiphobic properties and excellent anti-fingerprint property. The binding between cyclohexyl epoxy and glass substrate contributed to the high adhesion of the coating, which remained nearly intact and slightly reduced surface wettability after 500 friction cycles of sandpaper. In addition, the PVLE-I-200 coating demonstrated UV resistance which could withstand 200 h of UV irradiation attributed to the cage-like structure of VPOSS. The functional silicone coating provides insights into the development of environmentally friendly coatings for touch screens with high transparency, abrasion resistance, anti-smudge, and anti-fingerprint properties.
{"title":"Transparent, robust, and anti-fingerprint silicone coating with a three-dimensional cross-linked network enabled by hydrosilylation reaction","authors":"","doi":"10.1016/j.porgcoat.2024.108749","DOIUrl":"10.1016/j.porgcoat.2024.108749","url":null,"abstract":"<div><p>Silicone coatings with anti-smudge, anti-fingerprint, abrasion resistance, and ultraviolet (UV) resistance properties are increasingly demanded for touch screens as the development of artificial intelligence and human-computer interaction interfaces. Herein, a transparent, robust, and self-cleaning silicone coating was developed by incorporating cage-like structures and long carbon chains into a 3D cross-linked network via the rational combination of polymethylhydrosiloxane (PMHS), PSS-Octavinyl substituted (VPOSS), lauryl acrylate (LA), and 1,2-epoxy-4-vinylcyclohexane (EVCH) through hydrosilylation reaction with the presence of Karstedt catalysts. After introducing sealed diphenyliodonium phosphate (I-200), the silicone coating (PVLE-I-200) demonstrated excellent pencil hardness, anti-smudge, and abrasion resistance, and its average transmittance of visible light reached about 92 %. Owing to the low surface energy carbon chains, the coating showed amphiphobic properties and excellent anti-fingerprint property. The binding between cyclohexyl epoxy and glass substrate contributed to the high adhesion of the coating, which remained nearly intact and slightly reduced surface wettability after 500 friction cycles of sandpaper. In addition, the PVLE-I-200 coating demonstrated UV resistance which could withstand 200 h of UV irradiation attributed to the cage-like structure of VPOSS. The functional silicone coating provides insights into the development of environmentally friendly coatings for touch screens with high transparency, abrasion resistance, anti-smudge, and anti-fingerprint properties.</p></div>","PeriodicalId":20834,"journal":{"name":"Progress in Organic Coatings","volume":null,"pages":null},"PeriodicalIF":6.5,"publicationDate":"2024-08-24","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142048459","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":2,"RegionCategory":"材料科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Pub Date : 2024-08-23DOI: 10.1016/j.porgcoat.2024.108745
Chlorophyll (Chl), as a rich natural pigment, is limited in applications due to poor photostability. The hydrophobic properties of Chl attributed to the tetrapyrrole ring and terminal long-chain hydrocarbons further constrains its dispersion in aqueous coatings. In this work, chlorophyll/epoxy composite microspheres (Chl/EMs) were prepared as candidate pigments via emulsion polymerization to provide a versatile platform for enhanced dispersion and photostability. The optimal reaction temperature of 75 °C for achieving the appropriate particle size distribution of epoxy microspheres (EMs) was first determined. Chl/EMs were then prepared by (1) the combination of Chl and DGEBA in the emulsification process, or by (2) mixing Chl with m-xylylenediamine (MXDA) during curing. The effects of Chl introduction at different steps on the emulsification, curing agent diffusion, and curing process were studied using off-site microscopy observation and aggregation-induced emission technique, to clarify the structure and morphology evolution during emulsion polymerization. The particle size of the microspheres was mainly determined by the emulsification process of the epoxy precursor. Chl participates in emulsification of Chl/EMs in case (1), resulting in a large average particle size and poor particle size distribution. In case (2), the diffusion of MXDA into epoxy emulsion particles is completed within 30 min and does not impede the quicker diffusion process of Chl which was mixed with MXDA. The prepared Chl/EMs with size ranging from 1 to 10 μm create a conducive oxygen blocking environment. Compared to the complete degradation period of untreated Chl coatings, the photostability of Chl/EMs coatings increased nearly 7-fold. Remarkably, Chl/EMs exhibit superior dispersion capability in waterborne polyurethane coatings compared to pure Chl coatings. The EMs with controllable morphology and size can be used as a versatile platform for enhancing dispersion and photostability of other organic or natural dyes and pigments in waterborne coatings.
{"title":"Epoxy composite microspheres as a versatile platform for enhancement of chlorophyll dispersion and photostability in coatings","authors":"","doi":"10.1016/j.porgcoat.2024.108745","DOIUrl":"10.1016/j.porgcoat.2024.108745","url":null,"abstract":"<div><p>Chlorophyll (Chl), as a rich natural pigment, is limited in applications due to poor photostability. The hydrophobic properties of Chl attributed to the tetrapyrrole ring and terminal long-chain hydrocarbons further constrains its dispersion in aqueous coatings. In this work, chlorophyll/epoxy composite microspheres (Chl/EMs) were prepared as candidate pigments via emulsion polymerization to provide a versatile platform for enhanced dispersion and photostability. The optimal reaction temperature of 75 °C for achieving the appropriate particle size distribution of epoxy microspheres (EMs) was first determined. Chl/EMs were then prepared by (1) the combination of Chl and DGEBA in the emulsification process, or by (2) mixing Chl with <em>m</em>-xylylenediamine (MXDA) during curing. The effects of Chl introduction at different steps on the emulsification, curing agent diffusion, and curing process were studied using off-site microscopy observation and aggregation-induced emission technique, to clarify the structure and morphology evolution during emulsion polymerization. The particle size of the microspheres was mainly determined by the emulsification process of the epoxy precursor. Chl participates in emulsification of Chl/EMs in case (1), resulting in a large average particle size and poor particle size distribution. In case (2), the diffusion of MXDA into epoxy emulsion particles is completed within 30 min and does not impede the quicker diffusion process of Chl which was mixed with MXDA. The prepared Chl/EMs with size ranging from 1 to 10 μm create a conducive oxygen blocking environment. Compared to the complete degradation period of untreated Chl coatings, the photostability of Chl/EMs coatings increased nearly 7-fold. Remarkably, Chl/EMs exhibit superior dispersion capability in waterborne polyurethane coatings compared to pure Chl coatings. The EMs with controllable morphology and size can be used as a versatile platform for enhancing dispersion and photostability of other organic or natural dyes and pigments in waterborne coatings.</p></div>","PeriodicalId":20834,"journal":{"name":"Progress in Organic Coatings","volume":null,"pages":null},"PeriodicalIF":6.5,"publicationDate":"2024-08-23","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142044821","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":2,"RegionCategory":"材料科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Pub Date : 2024-08-23DOI: 10.1016/j.porgcoat.2024.108694
Passive daytime radiative cooling (PDRC) is an effective cooling method that operates without the need for external energy input, possessing the potential to reduce energy demand and mitigate the effects of global warming. In the past few decades, researchers have continuously explored and proposed a variety of multifunctional PDRC. In this regard, coating is a versatile and effective means to implement the PDRC technology. Currently, manufacturing PDRC coatings using a roll-to-roll process has made certain progress, and the way to prepare the coatings with lasting performance and achieve large-scale production has become the focus of current research. Firstly, this paper analyses the basic principles of PDRC. Then, it reviews the recent progress of PDRC coatings from the aspects of material design and application, and systematically analyses the advantages and potentials of PDRC coatings in a variety of fields, with particular attention to the feasibility of PDRC coatings promotion and application. Finally, to further promote the commercialization process of PDRC, the paper presents challenges that need to be addressed and long-term future directions for development.
{"title":"Recent advances in passive daytime radiative cooling coatings: Fundamentals, strategies and prospects","authors":"","doi":"10.1016/j.porgcoat.2024.108694","DOIUrl":"10.1016/j.porgcoat.2024.108694","url":null,"abstract":"<div><p>Passive daytime radiative cooling (PDRC) is an effective cooling method that operates without the need for external energy input, possessing the potential to reduce energy demand and mitigate the effects of global warming. In the past few decades, researchers have continuously explored and proposed a variety of multifunctional PDRC. In this regard, coating is a versatile and effective means to implement the PDRC technology. Currently, manufacturing PDRC coatings using a roll-to-roll process has made certain progress, and the way to prepare the coatings with lasting performance and achieve large-scale production has become the focus of current research. Firstly, this paper analyses the basic principles of PDRC. Then, it reviews the recent progress of PDRC coatings from the aspects of material design and application, and systematically analyses the advantages and potentials of PDRC coatings in a variety of fields, with particular attention to the feasibility of PDRC coatings promotion and application. Finally, to further promote the commercialization process of PDRC, the paper presents challenges that need to be addressed and long-term future directions for development.</p></div>","PeriodicalId":20834,"journal":{"name":"Progress in Organic Coatings","volume":null,"pages":null},"PeriodicalIF":6.5,"publicationDate":"2024-08-23","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142044822","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":2,"RegionCategory":"材料科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Pub Date : 2024-08-23DOI: 10.1016/j.porgcoat.2024.108755
Cryogenic conditions are of crucial importance for gas storage tanks to provide increased storage density, reduced pressure requirements and minimized energy losses. Incorporation of silica aerogel (SA) particles as a nanostructured material with extremely low density and exceptional thermal insulating properties into epoxy matrices has the potential to facilitate the progress of high performance nanocomposite coatings for advanced cryogenic applications. The objective of this study is therefore to investigate the impacts of particle size, particle content, milling method and mixing sequence on toughness of the cryo-conditioned epoxy coatings. SA particles of varying size (50 μm to 300 μm) were prepared using two different techniques (planetary ball milling vs. 2-blade grinding). Nanocomposite samples were prepared using two distinct mixing sequences, i.e., adding particles (in 0, 0.5, 1 and 1.5%wt.) to epoxy followed by mixing with hardener or adding particles to epoxy/hardener (with 3 or 15 min delay). The nanocomposite samples were subjected to different cryogenic conditions (single 3-h immersion in liquid nitrogen vs. three consecutive 1-h immersions). Mechanical properties of the samples were evaluated by conducting fractography, dynamic mechanical thermal analysis (DMTA) and tensile tests. Large SA particles settled towards the bottom of nanocomposite and resulted in loss of mechanical properties at cryo-conditions. Mixing 1 wt% of optimized SA particles with epoxy/hardener system led to an enhanced tensile strength (26 %), stiffness (3 %) and toughness (71 %) by providing uniform cross-linking reactions and mitigating thermal shock effects at cryo-conditions. Toughening mechanisms included crack deflection, crack pinning, crack arrest and crack branching.
低温条件对储气罐至关重要,可提高储气密度、降低压力要求并最大限度地减少能量损失。二氧化硅气凝胶(SA)颗粒是一种纳米结构材料,具有极低的密度和优异的隔热性能,将其掺入环氧树脂基质中有望促进高性能纳米复合涂层在先进低温应用领域的发展。因此,本研究旨在探讨粒度、颗粒含量、研磨方法和混合顺序对低温调质环氧涂层韧性的影响。采用两种不同的技术(行星球磨与双刀研磨)制备了不同大小(50 微米至 300 微米)的 SA 粒子。纳米复合材料样品的制备采用了两种不同的混合顺序,即在环氧树脂中加入颗粒(0、0.5、1 和 1.5%wt.),然后与固化剂混合,或在环氧树脂/固化剂中加入颗粒(延迟 3 或 15 分钟)。将纳米复合材料样品置于不同的低温条件下(在液氮中单次浸泡 3 小时与连续三次浸泡 1 小时)。样品的机械性能通过碎裂图、动态机械热分析(DMTA)和拉伸试验进行了评估。大的 SA 颗粒沉降到纳米复合材料的底部,导致低温条件下的机械性能下降。将 1 wt% 的优化 SA 粒子与环氧树脂/固化剂体系混合后,通过提供均匀的交联反应和减轻低温条件下的热冲击效应,提高了拉伸强度(26%)、刚度(3%)和韧性(71%)。增韧机制包括裂纹偏转、裂纹针刺、裂纹停止和裂纹分支。
{"title":"Synergic effects of silica aerogel (SA) particles on tensile behavior of cryo-conditioned epoxy: The role of particle morphology and mixing sequence","authors":"","doi":"10.1016/j.porgcoat.2024.108755","DOIUrl":"10.1016/j.porgcoat.2024.108755","url":null,"abstract":"<div><p>Cryogenic conditions are of crucial importance for gas storage tanks to provide increased storage density, reduced pressure requirements and minimized energy losses. Incorporation of silica aerogel (SA) particles as a nanostructured material with extremely low density and exceptional thermal insulating properties into epoxy matrices has the potential to facilitate the progress of high performance nanocomposite coatings for advanced cryogenic applications. The objective of this study is therefore to investigate the impacts of particle size, particle content, milling method and mixing sequence on toughness of the cryo-conditioned epoxy coatings. SA particles of varying size (50 μm to 300 μm) were prepared using two different techniques (planetary ball milling vs. 2-blade grinding). Nanocomposite samples were prepared using two distinct mixing sequences, i.e., adding particles (in 0, 0.5, 1 and 1.5%wt.) to epoxy followed by mixing with hardener or adding particles to epoxy/hardener (with 3 or 15 min delay). The nanocomposite samples were subjected to different cryogenic conditions (single 3-h immersion in liquid nitrogen vs. three consecutive 1-h immersions). Mechanical properties of the samples were evaluated by conducting fractography, dynamic mechanical thermal analysis (DMTA) and tensile tests. Large SA particles settled towards the bottom of nanocomposite and resulted in loss of mechanical properties at cryo-conditions. Mixing 1 wt% of optimized SA particles with epoxy/hardener system led to an enhanced tensile strength (26 %), stiffness (3 %) and toughness (71 %) by providing uniform cross-linking reactions and mitigating thermal shock effects at cryo-conditions. Toughening mechanisms included crack deflection, crack pinning, crack arrest and crack branching.</p></div>","PeriodicalId":20834,"journal":{"name":"Progress in Organic Coatings","volume":null,"pages":null},"PeriodicalIF":6.5,"publicationDate":"2024-08-23","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142044820","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":2,"RegionCategory":"材料科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Pub Date : 2024-08-23DOI: 10.1016/j.porgcoat.2024.108754
If not protected, underwater solar cells are encrusted with biological organisms, such as algae and barnacles, which lower the electrical or operational efficiency and are expensive to remove. We engineered a self-sustaining antifouling coating using ultra-low concentrations of nano-sized, seawater-soluble pigments, specifically cuprous oxide (Cu2O) and zinc oxide (ZnO), combined with an organic booster biocide and a fast-polishing binder material. This coating maintained high levels of visible light transmission for three months in tropical seawater without requiring human intervention, such as mechanical cleaning. Field tests demonstrated the coating's effectiveness in preventing biofouling, while preserving transparency. We anticipate that these self-sustaining antifouling coatings can be applied to thin, transparent, and interchangeable substrates for continual replacement on solar-powered autonomous underwater vehicles or solar cell platforms, thereby ensuring long-term operational efficiency.
{"title":"Self-sustaining antifouling coating for underwater solar cells","authors":"","doi":"10.1016/j.porgcoat.2024.108754","DOIUrl":"10.1016/j.porgcoat.2024.108754","url":null,"abstract":"<div><p>If not protected, underwater solar cells are encrusted with biological organisms, such as algae and barnacles, which lower the electrical or operational efficiency and are expensive to remove. We engineered a self-sustaining antifouling coating using ultra-low concentrations of nano-sized, seawater-soluble pigments, specifically cuprous oxide (Cu<sub>2</sub>O) and zinc oxide (ZnO), combined with an organic booster biocide and a fast-polishing binder material. This coating maintained high levels of visible light transmission for three months in tropical seawater without requiring human intervention, such as mechanical cleaning. Field tests demonstrated the coating's effectiveness in preventing biofouling, while preserving transparency. We anticipate that these self-sustaining antifouling coatings can be applied to thin, transparent, and interchangeable substrates for continual replacement on solar-powered autonomous underwater vehicles or solar cell platforms, thereby ensuring long-term operational efficiency.</p></div>","PeriodicalId":20834,"journal":{"name":"Progress in Organic Coatings","volume":null,"pages":null},"PeriodicalIF":6.5,"publicationDate":"2024-08-23","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://www.sciencedirect.com/science/article/pii/S0300944024005460/pdfft?md5=a6de3b5432760ef43b0648fb80afe034&pid=1-s2.0-S0300944024005460-main.pdf","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142044819","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":2,"RegionCategory":"材料科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Pub Date : 2024-08-22DOI: 10.1016/j.porgcoat.2024.108744
Biomimetic microvascular networks prepared by coaxial electrospinning technology have attracted much attention as a novel form of carrier for encapsulating active substances. However, the poor interfacial bonding strength between traditional electrospinning materials and metal substrates limits its application in anti-corrosion coatings. Herein, a novel poly(vinyl alcohol) grafted phytic acid (PVA-PA) electrospinning solution was synthesized. And a sandwich-like microvascular network (SMN) was prepared by coaxial electrospinning technology, which used PVA-PA solution as the shell material, epoxy resin 51 (E51), tetraphenylethylene (TPE) and polyamide resin as the core materials, respectively. Owing to the high porosity of SMN, epoxy resin can be directly spin-coated on it to form a composite coating (PVA-PA/SMN/EP). It is proved that due to the strong chelation and coordination interaction between PA and mild steel, the pull-out adhesion of the PVA-PA/SMN/EP composite coatings on mild steel was increased by 0.92 MPa. In addition, by systematically optimizing the relative viscosity, miscibility, conductivity, and saturated vapor pressure between the two jets of the core solution and the shell solution in coaxial electrospinning, the microvascular structure of the coaxial electrospinning nanofibers was improved and the fluidity of the internal active substances was maintained. When the PVA-PA/SMN/EP composite coating generates microcracks, the active substances encapsulated in the SMN flow out, in which the three-dimensional crosslinked network formed by the curing of E51 and polyamide resin enhances the spatial interactions between TPE molecules, which results in TPE emitting a bright blue fluorescence. This work provides a new approach for the development of the next generation of smart anti-corrosion coatings.
{"title":"Development of anti-corrosion coating with sandwich-like microvascular network for realization of self-healing and self-reporting properties based on coaxial electrospinning","authors":"","doi":"10.1016/j.porgcoat.2024.108744","DOIUrl":"10.1016/j.porgcoat.2024.108744","url":null,"abstract":"<div><p>Biomimetic microvascular networks prepared by coaxial electrospinning technology have attracted much attention as a novel form of carrier for encapsulating active substances. However, the poor interfacial bonding strength between traditional electrospinning materials and metal substrates limits its application in anti-corrosion coatings. Herein, a novel poly(vinyl alcohol) grafted phytic acid (PVA-PA) electrospinning solution was synthesized. And a sandwich-like microvascular network (SMN) was prepared by coaxial electrospinning technology, which used PVA-PA solution as the shell material, epoxy resin 51 (E51), tetraphenylethylene (TPE) and polyamide resin as the core materials, respectively. Owing to the high porosity of SMN, epoxy resin can be directly spin-coated on it to form a composite coating (PVA-PA/SMN/EP). It is proved that due to the strong chelation and coordination interaction between PA and mild steel, the pull-out adhesion of the PVA-PA/SMN/EP composite coatings on mild steel was increased by 0.92 MPa. In addition, by systematically optimizing the relative viscosity, miscibility, conductivity, and saturated vapor pressure between the two jets of the core solution and the shell solution in coaxial electrospinning, the microvascular structure of the coaxial electrospinning nanofibers was improved and the fluidity of the internal active substances was maintained. When the PVA-PA/SMN/EP composite coating generates microcracks, the active substances encapsulated in the SMN flow out, in which the three-dimensional crosslinked network formed by the curing of E51 and polyamide resin enhances the spatial interactions between TPE molecules, which results in TPE emitting a bright blue fluorescence. This work provides a new approach for the development of the next generation of smart anti-corrosion coatings.</p></div>","PeriodicalId":20834,"journal":{"name":"Progress in Organic Coatings","volume":null,"pages":null},"PeriodicalIF":6.5,"publicationDate":"2024-08-22","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142040150","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":2,"RegionCategory":"材料科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}