The application of water-based coatings, such as waterborne polyurethane (WPU) and polyurethane acrylate (WPUA), in harsh environments is often constrained by their moderate mechanical strength and limited water resistance. To overcome these limitations, this study developed a novel multi-crosslinked WPUA for use as anti-corrosion coatings. The precursors (PUUA and SPUUA) were partially end-capped with pentaerythritol triacrylate (PETA), which enabled the resulting polymer films to undergo post-crosslinking via UV irradiation in the presence of a photoinitiator, yielding cPUUA and cSPUUA, respectively. Moreover, ethylenediamine (EDA) and diethylenetriamine (DETA) were employed as chain extenders during the synthesis with the trifunctional DETA introducing a pre-crosslinked, branched structure into the precursors. Additionally, for SPUUA, partial end-capping with the silane coupling agent (3-aminopropyltrimethoxysilane, APTMS) allowed for self-condensation, forming additional siloxane crosslinks that enhanced the anticorrosion performance. This multi-crosslinking structure significantly enhanced the crosslinking density and hydrophobicity of the films, leading to substantial improvements in water resistance, mechanical properties, and anti-corrosion performance. This work provides a feasible strategy for designing high-performance, durable, and water-resistant polymer materials that align with environmental benefit, demonstrating the great potential for advanced anti-corrosion coatings.

Waterborne polyurethane acrylate (WPUA) has gained significant attention due to its environmental friendliness and versatile applications. However, its mechanical properties and water resistance often require improvement to meet industrial demands. In this study, we proposed a novel strategy based on the controlled deprotonation/protonation of amine moieties to enhance the water resistance and mechanical properties of WPUA by leveraging reversible electrostatic interactions. Herein, two types of WPUA were designed. One was synthesized through graft copolymerization of polyurethane (PU) prepolymer and acrylates, denoted as COPUA, while the other was referred to as CSPUA featuring a core-shell structure. Both types of WPUA utilized anionic PU with carboxyl groups as the macromolecular emulsifier. To simultaneously introduce both anionic and cationic groups into the aqueous system and avoid demulsification, an excess of alkaline neutralizing agent triethylamine (TEA) was added to suppress the protonation of amine moieties in the polyacrylate (PA) component. Therefore, hydrophobic amine monomers participated in copolymerization as much as possible inside the latex particles. This approach regulated the electrostatic interactions between polymers, endowing the latex with enhanced stability. During the room-temperature film formation process, as drying progressed and the alkaline neutralizer volatilized, the chain segments containing carboxyl and amine groups approached each other sufficiently and interacted, thereby constructing an ionic cross-linked network. The optimized intermolecular/intramolecular forces, led to a more robust and hydrophobic WPUA film featuring ionic bonds. The modified WPUA films exhibited significantly improved water resistance and a moderate enhancement in mechanical properties. This work provided a simple yet effective approach to designing high-performance WPUA, and the fundamental design principle could be applied not only to our current system but also to a broader range of applications, including coatings, adhesives, and sealants.

To address the hazards posed by ice accumulation on metal surfaces, combining efficient photothermal conversion ability with superhydrophobic properties has become an important direction for developing high-performance anti-icing/de-icing materials. In the present work, a superhydrophobic Cu/Mn@CeO2 coating was directly constructed on carbon steel substrates via a simple and eco-friendly one-step electrodeposition strategy. For detailed preparation parameters, the mass ratio of Cu2+ to Mn2+ within the electrolyte is regulated to 0.4:1, while 2.0g of CeO2 nanoparticles was introduced into the plating liquid. Subsequently, electrodeposition proceeds for 15min at a current density of 300A·m-2. The final coating delivers remarkable superhydrophobic properties, with an average water contact angle (WCA) recorded as 164.3 ± 0.5°. Moreover, the Cu/Mn@CeO2 coating possessed outstanding mechanical stability, and it maintained good superhydrophobicity even after 25 cycles of tape peeling, 720cm of sandpaper abrasion, and blade scratching tests. Electrochemical polarization tests in 3.5wt.% NaCl yielded an Icorr of 2.81 × 10-2A·m-2 and a corrosion protection efficiency of 96.13%. In comparison with bare steel and Cu/Mn coatings, the Cu/Mn@CeO2 coating showed an enhanced photothermal heating response and improved anti-icing performance. After 200s of continuous irradiation under a simulated solar light source, the Cu/Mn@CeO2 coating reached a surface equilibrium temperature of 73.32 °C. When tested at −20 °C, water droplets on the coating required 4800s to completely freeze. This coating provides a potential approach for developing durable anti-icing surfaces for engineering applications.

Waterborne polyurethane, with a mechanical strength comparable to solvent-based types, is eco-friendly and safe, using water as a dispersion medium. Polyacrylate excels in film formation and weather resistance but suffers from “hot stickiness and cold brittleness”. Merging polyurethane and polyacrylate creates advanced hybrids, while organosilicon enhances properties but is restricted due to hydrolytic crosslinking. In this paper, a series of polyurethane–polyacrylate hybrid latexes with high organosilicon content were prepared using phase inversion emulsion polymerization technology. Even when the monomer content of 3-(methacryloyloxy)propyltrimethoxysilane (MPS) was increased to 10%, the polymerization process was stable, without the formation of a gel precipitate. The resulting latexes could remain stable for at least 6 months without significant changes in the properties of their films. The effects of MPS content on the mechanical and thermal properties of latex films were systematically researched. The study showed that with an increase in MPS dosage, the hardness and elastic modulus of the latex films increased, while the elongation at break and water absorption decreased, together with the increased glass transition temperature and surface hydrophilicity. This work aims to provide new theoretical guidance for the preparation of silicone-modified hybrid latexes, enabling their safe and stable production and storage.

In this work, glass slides were separately silanized by silane coupling agents, 3-(trimethoxysilyl) propyl methacrylate (TPM) and 3-(mercaptopropyl) trimethoxysilane (MPS). Then, in presence of a photoinitiator, multifunctional hydrophilic coatings were fabricated facilely on these silanized glasses via UV-induced grafting polymerization of zwitterionic acrylic monomer methacryloxyethyl sulfobetaine (SBMA). The results showed that both TPM and MPS silanized glasses could participate in the UV-induced grafting polymerization of SBMA, while more SBMA could be grafted to the former glass to gain a little bit higher hydrophilicity. The structure, morphology and properties of the multifunctional glasses were investigated fully. As the hydrophilic polymer brushes poly(SBMA) (pSBMA) covalently attached to the glass surface, the glasses could render a series of excellent performances, including underwater superoleophobicity, anti-fogging, anti-frosting, abrasion resistance, self-cleaning and antibacterial adhesion, and especially high stability even after being immersed in water for 20 days. The strong interaction of pSBMA and water was confirmed via differential scanning calorimeter (DSC) and Raman spectrum analysis, to explicit the anti-fogging mechanism. Therefore, it is promising that the scalable multifunctional glass fabricated via UV-induced grafting polymerization could be potentially applied in the fields of automobile, bathroom, medical, etc.

In this study, a series of hindered urea bond (HUB) containing polyurethane-urea methacrylate prepolymers and a none HUB containing polyurethane methacrylate prepolymer were prepared using isobornyl methacrylate as the reactive diluent via one-pot procedure. The prepolymers were characterized fully by various techniques. Then, their thermosets were fabricated via UV curing in presence of a photo initiator, and their mechanical property and thermal behavior were investigated and compared. Different from the none HUB containing thermoset, the HUB containing thermosets (defined as PUT) could be recycled and reprocessed by hot press under relatively mild conditions with high recovery ratio of mechanical property. Furthermore, zinc oxide (ZnO) nanoparticles were modified with 3-(trimethoxysilyl) propyl methacrylate and the modified ZnO (defined as ZnO-TPM) was dispersed and polymerized into PUT matrix to prepare their nanocomposites. The influence of ZnO-TPM on the mechanical performance of the composites was evaluated, which indicated that the Young's modulus and tensile strength increased gradually to the maximum values at ZnO-TPM content of 1 wt% and then decreased. The composites also displayed good reprocessability with improved recovery ratio compared to the pure PUT sample. In addition, the composite materials exhibited strong UV absorption capacity, implying their potential application in the circumstance where UV-shielding was required.

It is highly desirable to construct stimuli-responsive nanocarriers for improving pesticides targeting and preventing the pesticides premature release. In this study, five new amphiphilic polymer emulsifiers with stimuli-responsive properties were designed and prepared via esterifying ethylene maleic anhydride copolymer (EMA) with straight chain alkyl alcohols (including n-octanol, n-decanol, n-dodecanol, n-tetradecanol, and n-hexadecanol), followed by ionizing the esterification products. The alkyl ester side groups in the polymer structure gave the emulsifiers multiple characteristics, including adjustable amphiphilicity, affinity to pesticide, ability to form micelle in water, cleavable dynamic covalent ester linkages, and the possibility of temperature-induced phase transition. With these emulsifiers, especially for the one with dodecyl ester side groups (defined as HEMA-C12), lambda-cyhalothrin (LC) was fabricated into the nanoemulsion with nanosized particles (71.1nm) via the phase inversion emulsification process. HEMA-C12 could also emulsify other hydrophobic pesticides, including avermectin, cyhalothrin, and bifenthrin, into nanoemulsions. The obtained LC nanoemulsion exhibited a series of advantages, including exceptional encapsulation efficiency (86.06%), high drug loading (52.10%), high stability towards shearing, storage and dilution, and high wettability, retention and adhesion to different leaves. In particular, the releasing of LC from the nanoparticles could be triggered by multidimensional stimuli, including pH, temperature, and esterase. The changes in structure and the stabilizing effect of HEMA-C12 under various stimuli were investigated to understand the releasing mechanism. Finally, the releasing profiles were fitted with different kinetic models to provide insights into the releasing behaviors. The releasing curves in the presence and absence of esterase conformed to the Logistic model, except for that at the benchmark condition (pH 7.0 and 25 ºC), which was controlled by the Korsmeyer-Peppas model and followed Fickian diffusion. Inspired by the rational-designed emulsifiers, a wide variety of novel polymer emulsifiers are expected to be developed for the construction of promising nanopesticide systems.

The development of intelligent multifunctional nanopesticides featuring enhanced foliage affinity and hierarchical target release is increasingly pivotal in modern agriculture. In this study, a novel cationic amphiphilic comb-shaped polymer, termed PEI-TA, was prepared via a one-step Michael addition between low-molecular-weight biodegradable polyethylenimine (PEI) and tetradecyl acrylate (TA), followed by neutralization with acetic acid. Using the emulsifier PEI-TA, a positively charged avermectin (AVM) nanoemulsion was prepared via a phase inversion emulsification process. Under optimal formulation, the obtained AVM nanoemulsion (defined as AVM@PEI-TA) demonstrated exceptional properties, including small size (as low as 67.6 nm), high encapsulation efficiency (up to 87.96%), and high stability toward shearing, storage, dilution, and UV irradiation. The emulsifier endowed AVM@PEI-TA with a pronounced thixotropy, so that the droplets exhibited no splash and bounce when they were sprayed on the cabbage leaf. Owing to the electrostatic attraction between the emulsifier and the leaf, AVM@PEI-TA showed improved leaf adhesion, better deposition, and higher washing resistance in contrast to both its negatively charged counterpart and AVM emulsifiable concentrate (AVM-EC). Compared to the large-sized particles, the small-sized particles of the AVM nanoemulsion more effectively traveled long distances through the vascular system of veins after entering the leaf apoplast. Moreover, the nanoparticles lost stability when exposed to multidimensional stimuli, including pH, temperature, esterase, and ursolic acid individually or simultaneously, thereby promoting the release of AVM. The release mechanisms were discussed for understanding the important role of the emulsifier in nanopesticides.

In this study, novel amphiphilic polymer emulsifiers for avermectin (Avm) were synthesized facilely via the hydrolysis of ethylene-maleic anhydride copolymer (EMA) with different agents, and their structures were confirmed by various techniques. Then, water-based Avm-nanoemulsions were fabricated with the emulsifiers via phase inversion emulsification process, and superior emulsifier was selected via the emulsification effects. Using the superior emulsifier, an optimal Avm-nanoemulsion (defined as Avm@HEMA) with satisfying particle size of 156.8 ± 4.9 nm, encapsulation efficiency (EE) of 69.72 ± 4.01% and drug loading capacity (DLC) of 54.93 ± 1.12% was constructed based on response surface methodology (RSM). Owing to the emulsifier, the Avm@HEMA showed a series of advantages, including high stability, ultraviolet resistance, low surface tension, good spreading and high affinity to different leaves. Additionally, compared to pure Avm and Avm-emulsifiable concentrate (Avm-EC), Avm@HEMA displayed a controlled releasing feature. The encapsulated Avm was released quite slowly at normal conditions (pH 7.0, 25 °C or 15 °C) but could be released at an accelerated rate in weak acid (pH 5.5) or weak alkali (pH 8.5) media or at high temperature (40 °C). The drug releasing profiles of Avm@HEMA fit the Korsmeyer–Peppas model quite well at pH 7.0 and 25 °C (controlled by Fickian diffusion) and at pH 7.0 and 10 °C (controlled by non-Fickian diffusion), while it fits the logistic model under other conditions (pH 5.5 and 25 °C, pH 8.5 and 25 °C, pH 7.0 and 40 °C).

To overcome the shortcomings of the temperature sensitivity of exterior flexible facing tiles (EFFIs), a series of crosslinking carboxylic styrene-acrylate (SA) latices were prepared via the semicontinuous seed emulsion polymerization of glycidyl methacrylate (GMA), methacrylic acid (MAA), acrylic acid (AA), butyl acrylate (BA), and styrene (St), and were applied as binders to fabricate EFFTs with mineral powder. The obtained latices exhibited Bragg diffraction because of the narrow particle size distribution. Owing to the low dosage of emulsifiers and the crosslinking reaction between the epoxy group and the carboxyl group, the latex films displayed excellent water resistance, with water adsorption as low as 7.1%. The tensile test, differential scanning calorimeter (DSC) test, and dynamic mechanical analysis (DMA) indicated that at a GMA dosage of 4–6% the latex films had high mechanical strengths, which remained relatively stable in the temperature range of 10 to 40 °C. The optimal AA dosage was found in the range of 2 to 3%, at which the wet mixture exhibited good processability, conducive to forming an EFFT with a compact microstructure. Using the optimal SA latex, the obtained EFFT displayed a series of improved performances, including low water absorption, high mechanical strength, and stable self-supporting ability over a wide temperature range, exhibiting the application potential in the decoration and construction industries.

In this article, high performance hydrophilic anti-icing coatings with carboxyl groups were facilely fabricated via UV curing polyurethane methacrylate prepolymers, which were prepared through polyaddition of isophorone diisocyanate (IPDI), poly(propylene glycol) (PPG), dimethylolpropionic acid (DMPA) and 2-hydroxypropyl methacrylate (HPMA) gradually in acetone (A series prepolymer) or isobornyl acrylate (IBOA) (B series pre -polymer), and finally treated with triethylamine (TEA). The structures of A series prepolymer and the corre-sponding cured coating were confirmed via various techniques. The anti-icing performance of the cured coatings was investigated by ice freezing delay test, ice adhesion strength test, water contact angle and water absorption tests, and DSC test. Based on the testing results, the anti-icing behavior was defined as the incomplete icing of water on hydrophilic surface to weaken the interface adhesion. The ice adhesion strength firstly decreased as the DMPA content increased. At DMPA content of 5 %, the coating displayed a stable and very low ice adhesion strength of 40 kPa even after 25 times of icing (at-12 degrees C) and de-icing (at 25 degrees C) cycling. At even higher DMPA content, the ice adhesion strength improved because of the anchoring effect of the ice. Moreover, when IBOA was used as reactive diluent and participated in the polymerization with the prepolymers, the obtained B series coatings could have much improved mechanical properties, together with low ice adhesion strength. The facile fabrication process, excellent anti-icing performance and adjustable mechanical properties should make the coatings suitable for various purposes.

A widely applicable one-step method to fabricate surface polymer nanofiber network structures via reversible addition-fragmentation chain transfer (RAFT) polymerization of N, N'-methylene bisacrylamide is presented. The morphological evolution process and adjusting parameters of obtained nanofiber networks are investigated. Modifications based on nanofiber networks to form strongly hydrophobic surface and hydrogel surface are conducted.

In this article, a novel slippery coating was fabricated from edible beeswax and sunflower oil via two steps. Firstly, an oleogel layer was formed on polyolefin substrate via cooling the hot beeswax and sunflower oil solution at ambient condition. Owing to the adsorption of the oleogel, sunflower oil was then sprayed and immobilized on oleogel layer to form the slippery coating with dual-layer structure. This solvent-free fabrication process was facile and green, and used only sustainable raw materials. The performances such as gel-to-sol dissociation temperature (defined as Tgel) and the adsorption for sunflower oil of the oleogel layers were modulated by the contents of beeswax. Sliding experiments on the slippery coating were carried out by using yogurt as the testing liquid. Owing to the liquid-liquid sliding, this coating displayed good sliding effect, thus greatly reducing yogurt adhesion on its surface. After thirty days storage in a refrigerator, this coating still exhibited the desired sliding effect for yogurt, revealing its application potential in reducing liquid food residue and waste.

In this study, a series of silica sol modified polyurethane composite emulsions were fabricated via incorporating silica sol precursor into anionic silanol-terminated polyurethane emulsion, which was obtained via three steps, including (1) reacting excess hexamethylene diisocyanate (HDI) with polybutylene glycol (PBG), 2,2-dimethyl-hydroxypropionic acid (DMPA), bis(2-hydroxyethyl) disulfide (HEDS) in a stepwise process using dibutyltin diacetate (DBTA) as the catalyst, (2) neutralizing the resulting prepolymer with triethylamine and end-capping with 3-aminopropyltriethoxysilane (APTES), and (3) dispersing the resulting silanol-terminated polyurethane in water under stirring. The reaction products were characterized by fourier transform infrared (FT-IR) spectroscopy, hydrogen proton nuclear magnetic resonance (H-1 NMR) spectroscopy, Raman spectroscopy and permeation gel chromatography (GPC). The swelling degree and gel content analysis confirmed the formation of crosslinking network in the composite coatings formed after drying the composite emulsions. The self-healing performances of the coatings were investigated by differential scanning calorimetry (DSC), dynamic thermo-mechanical analysis (DMA), scanning electron microscopy (SEM) and tensile mechanical tests, and the anti-fogging and anti-frosting behaviors of the composite coatings were analyzed by UV-visible spectroscopy, reflectance spectroscopy, water contact angle test and optical photometry. Based on the measurements, the self-healing process, the anti-fogging and anti-frosting mechanism were discussed. At suitable amount of HEDS, this coating exhibited excellent self-healing performances with the self-healing efficiency up to 95.9 % because of the high moving ability of the chains. After self-healing, these coatings displayed the same anti-fogging and anti-frosting properties as those before self-healing. The silica sol component was found to increasing both the polar groups and crosslinking degree, endowing the composite coating with durable anti-fogging and anti-frosting properties.

In this work, through the coordination of C3 symmetric azopyridine ligands and Ag(i), coordination polymers with azo groups on the main chain were prepared. The trans coordination polymer formed an organogel with a network of nanofibers at low critical gelation concentrations, and it exhibited the abilities of self-healing and multi-stimuli response to heating, light, mechanical shearing, and chemicals due to the presence of dynamic coordinating bonds. On the other hand, the cis coordination polymer was found to assemble into nanoparticles to give a responsive colloid, which can produce fibrous precipitation in several days upon visible light irradiation due to the isomerization of the azo groups. This work provides a novel example for the design of a multi-responsive organogel and colloid based on the structural transformation of coordination polymers.

Conducting polymer gels possess both gel-network structure and organic semiconductor properties, thus exhibit high energy density, excellent charge-discharge stability, and good flexibility, etc. They are considered as ideal materials for producing flexible electrodes, however the traditional fabrication of conducting polymer gels often introduced non-conducting chemical crosslinkers, limiting the electrical conductivity. In this work, a coordination polymer gel was employed as template to produce uniform network of polypyrrole nanowires, and after polymerization the template could be easily removed thereby improving the performance of the polypyrrole gel. The results showed that the polypyrrole gel fabricated by template method had a three-dimensional network structure composed of uniform nanowires, having good mechanical properties, large specific surface area, and excellent electrochemical properties. At a current density of 0.28 A/g, the specific capacitance could reach 450 F/g, meanwhile the the specific capacitance could be maintained at 88.6% after 1000 times charge-discharge cycles at a current density of 2.8 A/g. The polypyrrole nanowire network gels were loaded with glucose oxidase to give a flexible sensor, which had rapid responsiveness to glucose at low concentration (0. 2 mmol/L), therefore they were expected to have application in supercapacitors, electrochemical sensors and so on.

Polymer nanofibers with smooth surface were fabricated via conventional free radical polymerization of diurea type supramolecular gel fibers in cyclohexane. As the solvent polarity by using toluene increased, the product yield and fiber size increased, while the fibers changed from smooth to rough, together with more and more free particles. In the presence of polar methacrylic acid, both rough fibers and free particles were obtained when polymerized in cyclohexane. When nonpolar 2-(perfluoro-3-methylbutyl)ethyl acrylate (R-3420) was used, only polymer fibers with very smooth surface were formed. The morphologies of fluoropolymer samples changed from fibers to particles, while the fiber surface became rougher and rougher, as more and more ethanol was used. The hydrophobic fluoropolymer sample could extract toluene from water-toluene two-phase system. Compared with granular fluoropolymer samples, fibrous fluoropolymer samples displayed higher specific surface area and higher swelling ratio in toluene, and required a shorter time for toluene to flow through them.

A facile and highly efficiency one-step method to fabricate well-shaped polymer nano- and micro-hybrid hairy particles (PHPs) is presented via reversible addition–fragmentation chain transfer (RAFT) polymerization of N, N′-methylene bisacrylamide (MBA) in solution containing ethanol as solubility regulator. Separated and slightly connected PHPs with uniform micrometer core particles densely attached by nanometer hairs could be obtained without additional regulatory measures. The structures and morphologies of the resulting products are conformed by various techniques. The morphological evolution process and polymerization solution are investigated and discussed in detail to understand the fabrication mechanism. Moreover, surface fluorescent modification of PHPs and the difference in adsorption performance between PHPs and bald particles are studied to demonstrate the potentiality of PHPs for further functionalization and application.

In this article, a high performances hydrophilic tubular fluorescent sensor for Cu(II) detection was fabricated via immobilizing fluorophore 4-methoxy-1,8-naphthalimide groups on poly(N, N'-methylene bisacrylamide) (PMBA) microtubes. The modified polymer microtubes were characterized fully by SEM, FT-IR, EDS mapping, fluorescence microscope and fluorescence spectrometer. This fluorescent sensor displayed high fluorescence emission intensity at 457 nm under irradiation, and exhibited an obvious selective quenching effect in the presence of Cu(II) alone or with a variety of other cations in aqueous solution. Based on the fluorescence intensities before and after quenching, the concentration of Cu(II) could be calculated accurately. Moreover, the fluorescent sensor could be regenerated using ethylene diamine tetraacetic acid (EDTA) as the chelating agent. The regenerated sensor could be reused for many times without performance deteriorate. The mechanism of quenching and regenerating, and the role of the tubes were discussed.