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Poly(dimethylsiloxane) (PDMS) coatings are considered to be environmentally friendly antifouling coatings. However, the presence of hydrophobic surfaces can enhance the adhesion rate of proteins, bacteria and microalgae, posing a challenge for biofouling removal. In this study, hydrophilic polymer chains were synthesised from methyl methacrylate (MMA), Poly(ethylene glycol) methyl ether methacrylate (PEG-MA) and 3-(trimethoxysilyl) propyl methacrylate (TPMA). The crosslinking reaction between TPMA and PDMS results in the formation of a silicone-based amphiphilic co-network with surface reconstruction properties. The hydrophilic and hydrophobic domains are covalently bonded by condensation reactions, while the hydrophilic polymers migrate under water to induce surface reconstruction and form hydrogen bonds with water molecules to form a dense hydrated layer. This design effectively mitigates the adhesion of proteins, bacteria, algae and other marine organisms to the coating. The antifouling performance of the coatings was evaluated by assessing their adhesion rates to proteins (BSA-FITC), bacteria (B. subtilis and P. ruthenica) and algae (P. tricornutum). The results show that the amphiphilic co-network coating (e.g., P-AM-15) exhibits excellent antifouling properties against protein, bacterial and microalgal fouling. Furthermore, an overall assessment of its antifouling performance and stability was conducted in the East China Sea from 16 May to 12 September 2023, which showed that this silicon-based amphiphilic co-network coating remained intact with almost no marine organisms adhering to it. This study provides a novel approach for the development of high-performance silicone-based antifouling coatings. [ABSTRACT FROM AUTHOR]

Effective and easy regulation of hydrogel surface properties without changing the overall chemical composition is important for their diverse applications but remains challenging to achieve. We report a generalizable strategy to reconfigure hydrogel surface networks based on hydrogel–substrate interface dynamics for manipulation of hydrogel surface wettability and bioadhesion. We show that the grafting of hydrophobic yet flexible polymeric chains on mold substrates can significantly elevate the content of hydrophobic polymer backbones and reduce the presence of polar groups in hydrogel surface networks, thereby transforming the otherwise hydrophilic hydrogel surface into a hydrophobic surface. Experimental results show that the grafted highly dynamic hydrophobic chains achieved with optimal grafting density, chain length, and chain structure are critical for such substantial hydrogel surface network reconfiguration. Molecular dynamics simulations further reveal the atomistic details of the hydrogel network reconfiguration induced by the dynamic interface interactions. The hydrogels prepared using our strategy show substantially enhanced bioadhesion and transdermal delivery compared with the hydrogels of the same chemical composition but fabricated via the conventional method. Our findings provide important insights into the dynamic hydrogel–substrate interactions and are instrumental to the preparation of hydrogels with custom surface properties. It is useful to be able to control the surface properties of a hydrogel, but tuning the surface without altering bulk properties of the hydrogel is challenging. Here, the authors report a method for modifying the surface of a hydrogel by grafting of polymer chains to the mold. [ABSTRACT FROM AUTHOR]

As a growing number of protein drug products are developed, formulation characterization is becoming important. An IgG drug product is tested at concentrations from 0.0001–0.1 mg/mL for adsorption behavior to polymer surfaces polyvinyl chloride (PVC) and polypropylene (PP) upon dilution in normal saline (NS) using quartz crystal microbalance with dissipation (QCM-D). The studies mimicked IgG antibody interaction during IV administration with polymeric surfaces within syringes, lines, and bags. Drug product was characterized with excipients, with focus on surfactant. Drug solutions were run over polymer-coated sensors to measure the adsorption behavior of the formulation with emphasis on the behavior of each of the formulation's components. Over 60 sensorgram data sets were correlated with assayed protein solution concentrations in mock NS-diluted infusions of drug product in the equivalent concentrations to QCM experiments to build a preliminary predictive model for determining fraction of drug and surfactant adsorbed and lost at the hydrophobic surface during administration. These results create a method for reliably and predictively estimating drug product adsorption behavior and protein drug dose loss on polymers at different protein drug concentrations. [ABSTRACT FROM AUTHOR]

Ti3C2Tx MXene were modified by 3‐methacryloxypropyltrimethoxy silane (MPTS) and melamine quaternary ammonium salt (MG). The modification mechanism of MPTS and MG with Ti3C2Tx and the regulation of their surface and interfacial properties were confirmed through a series of tests. Ti3C2Tx@MPTS obtained by hydrolysis and hydroxyl co‐polycondensation had a hydrophobic surface and exhibits good dispersion stability. Ti3C2Tx@MG had a strong hydrophilic surface under the dual action of hydrogen bonding and electrostatic assembly, resulting in its surface charge changed from negative to positive. Furthermore, the morphologies of Ti3C2Tx@MPTS and Ti3C2Tx@MG were quite different. Compared with Ti3C2Tx MXene, Ti3C2Tx@MPTS still presents a multi‐layer structure, while Ti3C2Tx@MG shows a stripped‐off layer/single‐layer/partially collapse pattern. This is due to the fact that MPTS mainly modifies Ti3C2Tx MXene by coating, while MG is based on intercalation effect. The two modifiers modify Ti3C2Tx MXene with different effects, endow Ti3C2Tx MXene with different surface and interfacial properties, and then stabilize in the polymer matrix, supercapacitors and electrode materials in different ways. Highlights: The hydrophilic and hydrophobic Ti3C2Tx is realized by MG and MPTS.Layered morphology of Ti3C2Tx was changed with the introduction of MPTS and MG.The electronegativity of Ti3C2Tx was changed by the introduction of MPTS and MG. [ABSTRACT FROM AUTHOR]

Fused filament fabrication, commonly referred to as 3D printing, is an additive manufacturing method finding plenty of applications nowadays. In contrast, polymer nanopatterning by nanolithographic techniques plays an important role in obtaining functional surfaces and coatings for applications in different fields including micro‐ and nanoelectronics. In spite of their relevance, additive manufacturing and polymer nanolithography have not found yet a common niche to be developed. Although both approaches are oriented to achieve different types of objects, it is shown that the confluence of both technologies can be desirable and potentially convenient. Herein, it is demonstrated that by employing conventional 3D printing, it is possible to fabricate nanostructured polymer surfaces in a relatively simple way by using similar approaches as those used in nanoimprint lithography but without the need for clean room conditions. To do that, a printed‐assisted nanoimprint lithography concept (3DPrANIL) has been tested for different types of polymer and silicon templates. It is demonstrated that a polymeric nanostructured hydrophilic template can be replicated accurately on another polymer rendering a nanostructured surface with enhanced hydrophobicity. The results support 3DPrANIL as novel method to obtain micro‐ and nanostructured surfaces with different functionalities like iridescence and hydrophobicity. [ABSTRACT FROM AUTHOR]

The synthesis and use of polymer cubosomes have received significant attention in recent years. Polymer cubosomes are highly stable colloidal particles with triply periodic minimal surface. Inherently, polymer cubosomes have several advantages over other nanostructures like micelles and vesicles as they are quite uniform and porous structures. Due to the large specific surface area of the interior and bicontinuous nature, they have the capacity to load significant amounts of hydrophobic and hydrophilic substances. Additionally, their properties make them suitable for use as nanotemplates, catalyst supports, and nanovehicles for the separation and regulated release of biomolecules. Regarding their synthesis, block copolymers that may form cubosomes are still few in number, in part because different block copolymers require various self-assembly conditions. In order to create polymer cubosomes, five different self-assembly techniques have been reported, including the co-solvent method, flash nanoprecipitation, evaporation-induced self-assembly, solvent-diffusion-evaporation-mediated self-assembly, and polymerization-induced self-assembly. This review article describes various synthetic techniques for creating polymer cubosomes and goes into further depth on recent uses for polymer cubosomes. It is anticipated that this article may offer some helpful guidance to researchers interested in the different applications of polymer cubosomes. [ABSTRACT FROM AUTHOR]

Surface hydrophobic modification is a critical technology for enhancing the application properties of materials, crucial for the development of geopolymer materials in oil-water separation. in this study, a lightweight porous slag-based geopolymer highly hydrophobic materials (PSGHHMs) were successfully prepared in-situ using slag and liquid water glass by varying different influencing factors, such as the amount of water/foaming agent/polymethylhydrosiloxane (PMHS) and the curing temperature. The PSGHHMs exhibited high strength, large flux and excellent highly hydrophobic properties, with contact angle reaching 156.14° and a sliding angle of less than 2°. SEM-EDS, TG-DSC and FT-IR analysis reveal that the in-situ modification mechanism of PSGHHMs involves the hydrolysis of Si-H in PMHS under alkaline conditions to form Si-OH. This subsequently reacts with Ca-OH in C-S-H gel to produce Ca-O-Si. Consequently, the PSGHHMs retained their excellent highly hydrophobicity even after calcination at 450℃ for 2.5 h. The PSGHHMs demonstrated robust resistance to acid/alkali/salt corrosion, as well as to friction, with the ability to quickly restore damaged highly hydrophobic properties. Additionally, the PSGHHMs could quickly absorb light/heavy oils, and achieving a desorption efficiency of over 99 %. They were also capable of continuously separation of oil-in-water emulsions and oil-water mixtures. Given these properties, the PSGHHMs have broad potential applications in antifreezing, antifogging, drag reduction and oil-water separation. [Display omitted] • Preparation of PSGHHMs with high strength and flux by simple coating method. • PSGHHMs have outstanding resistance to high temperature, friction and acid/alkali/salts. • PSGHHMs have excellent anti-fouling, highly hydrophobic and superoleophilic. • PSGHHMs achieve continuous separation of oil-water emulsions and oil-water mixtures. • Providing a new idea for industrial oil-water separation. [ABSTRACT FROM AUTHOR]

• PNIPAm-based HCM with cavitands as nanocontainers was developed for protein absorption. • The hydrogel structure is modified by cavitands and validated by MD simulation. • Fabricated HCM exhibits good structural stability and robust BSA separation performance. Protein adsorption is of great significance for bioengineering, biomedicine, drug release, etc. Herein, poly- N -isopropylacrylamide (PNIPAm) and polyethylene glycol diacrylate (PEGDA) based hydrogel materials were used to introduce self-synthesized cavitands with pore cage structures and hydrophobic characteristics to construct high-efficiency hydrogel composite membrane (HCM) for the adsorption of bovine serum albumin (BSA). The hydrophobic cavitand cage can improve the interfacial polymerization process by impacting the monomer diffusion and then modifying the interface properties of the hydrogel molecular network, which is validated by the molecular dynamic simulation. The adsorption mechanism can be interpreted as the reorganization of the polymer pores using the cavitands, and hence the surface charge and hydrophobic property consequently changed, which is consistent with the measurement results as well as validated by the molecular dynamic simulation. Thus, the fabricated HCM exhibits good structural stability, thermal stability, and robust BSA adsorption performance. The results indicated that the developed HCM materials can be promising candidates for effective protein separation. [ABSTRACT FROM AUTHOR]

[Display omitted] • Acrylic acid and hydrophobic monomer form low swelling hydrogel. • Semi-interpenetrating polymer network helps to reduce swelling ratio. • This hydrogel is moldable and salt stimulus responsive. • This gel has a switchable hydrophobic or hydrophilic surface. • It has adjustable swelling ratio along with low swelling properties in brines. Low swelling hydrogels have attracted much attention because of good mechanical stability, whereas they suffer the shortcoming of high cost. Here, we demonstrate a low-cost low swelling hydrogel which produced using acrylic acid as the main precursor. This hydrogel has a switchable hydrophobic or hydrophilic surface depending on the copolymerized monomers and adjuvants. The gel is moldable and flexible. In fresh water, swelling ratio of the gel is around 0.2 g/g. In saline solutions, it has adjustable swelling ratio while maintaining low swelling properties. This gel has the characteristics of a low BET surface area of 3.9758 m2/g and an average pore diameter of 20 nm. The gel could be used as a smart adaptive material and shape-stable adsorption material in saline environments. [ABSTRACT FROM AUTHOR]

A simple and robust method is presented to immobilize a heparin‐analog polyelectrolyte on inert hydrophobic surfaces. It is demonstrated that an amphiphilic block copolymer consisting of linear polyglycerol sulfate (lPGS) and a benzophenone modified anchor block can be bound to polystyrene surfaces in a facile dip‐coating procedure. The chaotropic salt guanidinium chloride is used to overcome the aggregation of the polymer as well as the repulsion between highly hydrated sulfate groups and the polystyrene surface. Irradiation with UV light tethers the polymer chains covalently to the surface. The resulting coating exhibits an aggregate morphology that resembles the aggregation behavior in solution, with a coating thickness of 8 nm. The behavior of the surfaces is dominated by the polyelectrolyte brush coating. They swell and collapse in response to different ionic strengths of the surrounding medium, and bind proteins via electrostatic interactions. The coating is stable toward physiological conditions over the course of several weeks. Coated surfaces bind to proteins of the complement cascade when in contact with dilute blood serum, which results in a decrease of complement activity to 78 ± 4%. The coating procedure can also be applied to other nonactivated polymer surfaces, as demonstrated on a polypropylene fleece. [ABSTRACT FROM AUTHOR]

The interactions of molecules and particles in solution often involve an interplay between isotropic and highly directional interactions that lead to a mutual coupling of phase separation and selfassembly. This situation arises, for example, in proteins interacting through hydrophobic and charged patch regions on their surface and in nanoparticles with grafted polymer chains, such as DNA. As a minimal model of complex fluids exhibiting this interaction coupling, we investigate spherical particles having an isotropic interaction and a constellation of five attractive patches on the particle's surface. Monte Carlo simulations and mean-field calculations of the phase boundaries of this model depend strongly on the relative strength of the isotropic and patch potentials, where we surprisingly find that analytic mean-field predictions become increasingly accurate as the directional interactions become increasingly predominant. We quantitatively account for this effect by noting that the effective interaction range increases with increasing relative directional to isotropic interaction strength. We also identify thermodynamic transition lines associated with self-assembly, extract the entropy and energy of association, and characterize the resulting cluster properties obtained from simulations using percolation scaling theory and Flory-Stockmayer mean-field theory. We find that the fractal dimension and cluster size distribution are consistent with those of lattice animals, i.e., randomly branched polymers swollen by excluded volume interactions. We also identify a universal functional form for the average molecular weight and a nearly universal functional form for a scaling parameter characterizing the cluster size distribution. Since the formation of branched clusters at equilibrium is a common phenomenon in nature, we detail how our analysis can be used in experimental characterization of such associating fluids. [ABSTRACT FROM AUTHOR]

Aqueous zinc-ion batteries (AZIBs) have superiorities such as high safety, low redox potential and low cost, but they still have the disadvantages of uncontrollable zinc dendrite growth, severe corrosion, and hydrogen evolution reactions. This study synthesized a porous organic polymer based on anthraquinone and triazine units (C-PAT) and used it as a protective coating for zinc anode of AZIBs. Profiting by high hydrophobicity of C-PAT, the electrode-electrolyte interface corrosion was reduced, thus achieving a stable Zn anode with low interface impedance. The symmetrical battery assembled with Zn anode modified with C-PAT could stably cycle for 1820 h maintaining a lower polarization voltage of 33 mV at 0.25 mA cm−2. The full battery (C-PAT@Zn//NHVO) shows a high initial capacity of 358.2 mAh g−1 at 1 A g−1 and displays an impressive cycling performance with high reversible capacity of 191.5 mAh g−1 after 300 cycles. This study could provide a new course for the application of porous organic polymers as the protective coatings of Zn anode to obtain long-life AZIBs. We synthesized a triazine-based porous aromatic organic polymer through a simple nucleophilic substitution reaction and applied it as the protective coating for Zn anode of aqueous zinc-ion batteries. Thanks to the high surface area and hydrophobic properties of the polymer, this protective coating strategy effectively inhibits Zn dendrite growth and corrosion, thus obtaining a stable Zn anode with ultra-low interface impedance. [Display omitted] • Porous organic polymer based on anthraquinone and triazine C-PAT is synthesized. • The C-PAT is used as a protective coating for zinc anode of aqueous zinc-ion batteries. • Cells assembled with C-PAT@Zn electrode have ultra-low interface impedance. • The C-PAT coating inhibits the dendrite growth and corrosion issues of Zn anodes. [ABSTRACT FROM AUTHOR]

The ability to regulate the spatial distribution of nanoparticles to generate patterns/arrays makes them promising applications in various fields. Here, a versatile and potential method, based on the polymer brushes patterned surface with hydrophilic-hydrophobic contrast characteristic, was developed to create the nanoparticle patterns with complicated architectures and controllable structural colors on the silicon/glass substrate. Employing DMD-mediated Photo-ATRP process, the selective growth of hydrophilic poly (ethylene glycol) methyl acrylate (PEGMA) brushes on the surface functionalized with hydrophobic initiators was achieved. Subsequently, the as-obtained hydrophilic-hydrophobic patterned substrate was acted as a template for regulating the assembly behavior and spatial arrangement of polystyrene (PS) nanoparticles, leading to the generation of nanoparticle patterns with desired architectures. Especially, the assembly densities could be controlled via tuning the grafting density of patterned PEGMA brushes, which enabled the effective regulation of structural color on the patterned surface. On the basis of the spatiotemporal control of patterned hydrophilic region formation, the sequential assembly of different nanoparticles on the same substrate could be achieved, allowing for a multi-component nanoparticle pattern for structural color-based anticounterfeiting application. The presented technique for the creation of nanoparticle patterns/arrays exhibits a tremendous practical potential in various fields including high-throughput preparation of structural colors, anticounterfeiting/ information encryption, and optical hypersurfaces. [Display omitted] • The PEGMA brushes patterned surface with discontinuous hydrophilic regions was fabricated. • Nanoparticles were assembled selectively on the PEGMA brushes patterned surface. • Nanoparticle patterns with variant densities and compositions were achieved. • Structural colors were produced on the surface of nanoparticle patterns. • A two-component nanoparticles pattern was constructed for anticounterfeiting application. [ABSTRACT FROM AUTHOR]

Hydrophobic surfaces and super hydrophobic surfaces have been widely studied and applied to cotton, ceramics, glass and other surfaces, but less research has been done on environmentally responsive hydrophobic surfaces (ERHS). In this paper, the environmentally responsive low fluorine epoxy copolymer P(DMAEMA- r -TFEMA- r -GMA) was synthesized by traditional free radical polymerization and the obtained copolymer was applied to construct ERHS on the cotton fabric and wood/plastic composite (WPC). The effects of construction parameters (polymer concentration, pH value of impregnation solution, impregnation temperature, impregnation time, drying temperature and drying time) on the surface hydrophobic properties of cotton fabric and WPC were studied. L 25 (56) orthogonal experiment scheme was selected to explore the optimal parameters of hydrophobic construction. The optimum construction conditions of ERHS cotton and ERHS WPC were as follows: polymer concentration of 10 mg/mL, impregnation time of 9 h, pH of 9, impregnation temperature of 50 °C and 60 °C, drying time of 6 h, and drying temperature of 120 °C. The maximum water contact angle (WCA) on the surface of ERHS cotton was 145°. After 15 times pH-stimulation circulations, the WCA changed in the range of 145° ± 5° to 120° ± 5°. After 10 times acid-base response circulations, ERHS cotton had good oil-water separation capacity, and the maximum oil-water separation rate varied from 99.82% to 98.24%. This hydrophobic modification had no effect on the thermal stability of cotton fabric. The maximum WCA of ERHS WPC was 135°. Under acidic conditions (pH=2), the water absorption rate of wood plastic was improved. The hydrophobic modification had little effect on the mechanical properties and thermal stability of WPC. [Display omitted] • The pH responsive copolymer P(DMAEMA- r -TFEMA- r -GMA) was applied to construct environmentally responsive hydrophobic surfaces. • In order to explore the optimal parameters of hydrophobic construction, L 25 (56) orthogonal experiment scheme was selected. • The hydrophobic modification had little effect on the mechanical properties and thermal stability of WPC. [ABSTRACT FROM AUTHOR]

In order to improve hydrophobic surfaces with low fluorine content, an incomplete fluoroalkyl-capped polyhedral oligomeric silsesquioxane (ap-FPOSS) was synthesized as an initiator and used to initiate methylmethacrylate (MMA) to produce polymer ap-FPOSS-PMMA100,150,200 by atom transfer radical polymerization (ATRP). Compared with fluorine-free ap-POSS-PMMA and PMMA polymers, the films cast from 200 to 470 nm core-shell micelles self-assembled by the obtained ap-FPOSS-PMMA presented higher water contact angles (114°–124°), lower surface energy (9.6–14.9 mN·m−1), lower water absorption (Δf = 270 Hz), and lower viscoelasticity (Δf/ΔD = −1.7 HZ×106), which were attributed to their increased surface roughness and fluorine content. Additionally, ap-FPOSS-PMMA exhibited a much higher thermostability (Tg>120°C, Td>380°C) and light transmission (>97%) than fluorine-free polymer of ap-POSS-PMMA. The application of ap-FPOSS-PMMA proved that the low fluorine component in ap-FPOSS was able to produce a highly hydrophobic coating on a cotton surface (122°–124°). [ABSTRACT FROM AUTHOR]

Fungal sporulation is affected by many environmental factors, for example, we previously observed that embedding of a hydrophobic polymer net in an agar plate medium significantly accelerates spore formation of some fungi. Here, it was found that the fungal spore formation depended on the surface hydrophobicity of cultivation vessels used for the plate cultivation. In a polypropylene (PP) vessel, six fungal strains produced spores of 1.5 to 514.8 times of those growing in a glass vessel. The contact of vegetative hyphae on the surface of the vessels might trigger the fungal spore formation. Moreover, the spore formation was synergistically accelerated by the reduction of nitrogen source content in an agar plate medium and by the contact to hydrophobic polymers. The synergistic effect depended on the surface area of the hydrophobic polymer. Thus, the combination of the reduction of nitrogen source and the embedding of hydrophobic polymer is expected as a novel and effective procedure for production of fungal spores which are useful for the inoculum in fermentation industry and biocontrol agent in agriculture. [Display omitted] • The higher the hydrophobicity of culture vessel, the more the spore formation. • Spore production in polypropylene vessel reached 1.5 to 514.8 times of glass one. • N-source reduction and hydrophobicity synergistically accelerated spore formation. • The synergistic effect depended on the surface area of hydrophobic polymer. [ABSTRACT FROM AUTHOR]

A facile and inexpensive way have been developed to fabricate robust self‐cleaning superhydrophobic coating by depositing polymer layer on candle soot (CS) surface using dip coating method. The stability and robustness of the CS deposited superhydrophobic surface is much weaker due to weak interaction and nonchemical bonding with the substrate. We introduced a thin layer of polystyrene, polyethylene, polypropylene (PP), and polyvinylidene fluoride on CS surface in order to improve its mechanical properties. The fabricated surfaces with the use of respective polymers exhibited water contact angles of nearly 170, 174, 175, and 171° with sliding angles of 2, 1, 1, and 3°, respectively. Although, all the polymers used in this work exhibited excellent superhydrophobic and self‐cleaning surface property, we found that the PP deposited CS surface exhibit better stability against water jet hitting and water drop impact tests. The PP deposited CS surface almost maintained their surface properties even after 50 cycles of sandpaper abrasion and 20 cycles of adhesive tape peeling tests. The mechanical durability tests confirmed that PP is a better polymer to improve the long‐term durability of CS surface. Therefore, this simple, time saving, and inexpensive method for fabricating superhydrophobic coating can be used for potential industrial application. [ABSTRACT FROM AUTHOR]

Cost‐effective separation of oil and immiscible organic contaminants from water has become an urgent challenge to protect aquatic and human life from devastating effects. Therefore, it has become imperative to develop super‐selective materials for efficiently separating oil from water. In this work, a superhydrophobic surface has been formed that consists of a silane@polystyrene‐coated polypropylene fibrous network (silane@PS‐PPF) for efficient separation of accidentally spilled oil from water. The superhydrophobic PPFs were designed by a simple, cost‐effective two‐step process that includes photochemically controlled polymerization of styrene and subsequent dip coating in octadecyltrichlorosilane solution. The hydrophobic surface (CA=129°±4°) of the PS coated PPF after treating with silane was turned into a superhydrophobic body (CA=161°±2°). The achieved silane@PS‐PPF fibrous network selectively allowed the fast permeation of the oils and non‐polar organic liquids by altogether rejecting water during operation. The separation efficiency for various oils from the contaminated water was 96 to 99%, with a high flux in the range of 7606±312 L m−2h−1 to 9870±151 L m−2h−1. Apart from being used as a filter, the silane@PS‐PPF was also used as an oil absorber and has shown an absorption capacity in the range of 1185 to 1535% for various oils. We anticipate that the developed silane@PS‐PPF, due to its facile synthetic route, cost‐effectiveness, and high performance, can be effectively used in oily wastewater treatment and clean‐up of large oil spills from water. [ABSTRACT FROM AUTHOR]

Development of a universal and stable surface coating, irrespective of surface chemistry or material characteristics, is highly desirable but has proved to be extremely challenging. Conventional coating strategies including the commonly used catechol surface coating are limited to either a certain type of substrates or weak and unreliable surface bonding. Here, a simple, robust, and universal surface coating method capable for attaching any stimuli‐responsive glycidyl methacrylate (GMA)‐based copolymer, consisting of one surface‐adhesive moiety of epoxy groups and one stimuli‐responsive moiety, to any type of hydrophobic and hydrophilic surfaces via a one‐step ring‐opening reaction is proposed and demonstrated. The resultant GMA‐based copolymers are not only strongly adhered on different substrates (e.g., silicon, polypropylene, polyvinyl chloride, indium tin oxide, polyethylene terephthalate, aluminum, glass, polydimethylsiloxane, and even polyvinylidene fluoride with low surface energy), but also are possessed distinct thermal‐, pH‐, and salt‐responsive functions of bacterial killing, bacterial releasing, tunable multicolor fluorescence emission, and heavy metal detection. This coating method is also compatible with the directional quaternization of GMA‐based copolymers for further improving surface adhesion and functionality. This study provides a simple yet universal coating method to solve the long‐standing challenge of robust integration of stimuli‐responsive polymers with strong adhesion between various polymers and substrates. [ABSTRACT FROM AUTHOR]

Since nanodiamonds (NDs) have been attracting growing interest in the field of nanomedicine, aqueously dispersed NDs have been numerously prepared by surface functionalization with hydrophilic groups. In contrast, hydrophobic NDs dispersible in organic solvents have been elusive in spite of the various potential applications such as tribology, lubrication and abrasion. Herein, NDs with a diameter of 100 nm (ND100) are made to be dispersible in an organic solvent through the following two processes: 1) ring opening polymerization of 1,2‐epoxyhexane giving NDs functionalized with poly(1,2‐hexylene glycol) (ND‐PHG) and 2) ring opening polymerization of glycidol followed by Williamson ether synthesis giving NDs functionalized with octyl and tetradecyl groups (ND‐POPG and ND‐PTPG, respectively). These functionalized NDs are characterized qualitatively by Fourier transform infrared spectroscopy (FTIR) and quantitatively by thermogravimetric analysis (TGA). All these NDs with hydrophobic polymers are dispersible in chloroform, while no dispersibility is observed in NDs without surface polymer coating. ND‐POPG and ND‐PTPG are found to show much higher dispersibility (∼5 mg/mL in chloroform) than ND‐PHG (∼0.3 mg/mL). The dispersibility or hydrophobicity is correlated with the number of the alkyl chains, determined by TGA, as well as their length. [ABSTRACT FROM AUTHOR]

Modification of the surface of polyvinyl chloride (PVC) deposited on a copper foil under the influence of nanosecond laser radiation with different peaks fluence was studied by using infrared spectroscopy of attenuated total reflection and optical microscopy. The dependences of the wetting angle of the texture surface with water on the peak fluence of laser radiation were measured. The obtained various relief textures demonstrate a sharp drop in water contact angles from (∼50°) to super hydrophilic (∼15°), which allows us to design and fabricate micro-scale elements of laboratory devices for the tasks of bactericidal treatment, collection and removal of liquids, as well as their separation and purification. A stable increase in the contact angles of water with the surface of the textures to hydrophobic (up to ∼140°) observed over time indicates degradation of the polymer coating. [ABSTRACT FROM AUTHOR]

New nanoparticles are synthesized through emulsion polymerization, using distinct comonomers (styrene, divinylbenzene, glycidyl methacrylate and pentafluorostyrene). Then, for the first time, two strategies are adopted to functionalize such nanoparticles using benzylamine and thiophenol: (i) after the manufacture of the nanoparticles; and (ii) in situ during the polymerization reaction. Afterwards, the functionalized nanoparticles are used as nanosupports for immobilization of lipase B from Candida antarctica and the performance of the novel nanobiocatalysts are evaluated. It is shown that the nanoparticles exhibit different properties (specific areas ranging from 34 m2 g−1 to 324 m2 g−1; and contact angles ranging from 29° to 126°), indicating that both procedures can be used to adjust the properties of the polymer supports. Moreover, the nanobiocatalysts are applied successfully in hydrolysis and esterification reactions, exhibiting higher activities than the non‐functionalized biocatalysts. It is also observed that more hydrophilic supports result in more active biocatalysts in hydrolysis (27 ± 1 U g−1) and intermediate hydrophobic matrices conduct to more active biocatalysts in esterification reactions (1564 ± 50 U g−1). It is shown that highly hydrophobic surfaces may cause a significant decrease in the activity of such biocatalysts, probably due to distortions on the enzyme active center and to more intense chemical partitioning effects. [ABSTRACT FROM AUTHOR]

The novel hydrophobic coating material was received for the first time by a two‐step synthetic route. Firstly, the 15‐functional brominated macroinitiator was prepared by the esterification methodology. Next step covers synthesis of star‐like polymers by poly(n‐butyl acrylate) (PBA) arms polymerization via three low‐ppm atom transfer radical polymerization (ATRP) approaches including application of copper and silver wire in SARA and ARGET ATRP, respectively, as driving forces in redox cycle of catalyst, and an external stimulus in the form of electric current (seATRP) as the third approach in copper(II) regeneration system. As expected, the electrochemically mediated technique allows synthesis of tannic acid‐inspired coating polymers in precisely controlled manner during the entire polymerization process, proved by linear first‐order kinetics plot in contrast to above‐mentioned methods, low dispersity (Ð = 1.18) of star‐shaped polymers, and high efficiency of initiation (ƒi = 81%) determined after detaching of polymers side arms. Macromolecules received by all low‐ppm ATRP solutions were characterized by preserved chain‐end functionality (theoretical dead chain fraction; DCFtheo <1%). Adhesive and hydrophobic properties of received polymer materials were investigated by contact angles (θ) and free surface energy (FSE) calculations. Prepared polymer films besides excellent hydrophobic properties have great potential as a self‐healing solution. [ABSTRACT FROM AUTHOR]

Cargo transport through the nuclear pore complex continues to be a subject of considerable interest to experimentalists and theorists alike. Several recent studies have revealed details of the process that have still to be fully understood, among them the apparent nonlinearity between cargo size and the pore crossing time, the skewed, asymmetric nature of the distribution of such crossing times, and the non-exponentiality in the decay profile of the dynamic autocorrelation function of cargo positions. In this paper, we show that a model of pore transport based on subdiffusive particle motion is in qualitative agreement with many of these observations. The model corresponds to a process of stochastic binding and release of the particle as it moves through the channel. It suggests that the phenylalanine-glycine repeat units that form an entangled polymer mesh across the channel may be involved in translocation, since these units have the potential to intermittently bind to hydrophobic receptor sites on the transporter protein. [ABSTRACT FROM AUTHOR]

In this paper, Brownian dynamics simulation (BDS) studies are executed to demonstrate the distinctive influences of the extent of confinement on the collapsing mechanism and kinetics of a flexible hydrophobic polymer chain in a poor solvent. The collapsing behavior is quantified by the time of collapse, which below a critical dimension of the confinement (hc), encounters a drastic reduction with a further strengthening in the degree of confinement. For dimensions greater than this critical one, the collapse occurs through the well-known hydrodynamic interaction (HI) controlled multiple-globule-mediated mechanisms. However, for channel dimensions less than this critical one, the collapse mechanism is drastically altered. Under such circumstances, the collapse gets predominantly controlled by the confinement effects (with negligible contribution of the HIs) and occurs via the formation of a single central globule. This central globule rapidly engulfs the noncondensed polymer segments, and in the process largely hastens up the collapsing event. Under such circumstances, the collapse time is found to decrease linearly with decrements in the channel height. On the contrary, for channel heights greater than hc, the multiple-globule-mediated collapse is characterized by a collapse time that shows an exponential dependence on the channel height, rapidly attaining a state in which the confinement effect becomes inconsequential and HIs dictate the entire collapsing behavior. We further propose detailed arguments based on physical reasoning as well as free energy estimations to conclusively support the qualitative and quantitative nature of influences of the confinement on the polymer collapse. [ABSTRACT FROM AUTHOR]

Surface biofunctionalization of the hydrophobic lanthanide ion doped hexagonal phase NaYF4:Yb,Er upconversion nanophosphors (UCNPs) was achieved by introducing amino and carboxyl groups, respectively. Amino groups were added by using the 3-aminopropyltrimethoxysilane reaction after a thin layer of SiO2 coating. The carboxyl groups on surface were added directly by coating modified amphiphilic polyacrylic acid polymer. Experimental studies of cytotoxicity and cell uptake of UCNPs were conducted. The cytotoxicity analysis of the functionalized UCNPs was conducted by methylthiazol tetrazolium assays. Cell uptake was accomplished by incubating the UCNPs with human osteosarcoma cells and proved by transmission electron microscopy. The results showed that the functionalized UCNPs had very low toxicity compared with the control group, while UCNPs taken into the cells indicated that they had very high biocompatibility. The imaging of UCNPs, which were incubated with AB12 mouse mesothelioma cells and excited by 1 W 980 nm light, showed individual particles with visible light emission. These results exhibited promising applications of functionalized UCNPs in cell imaging and photodynamic therapy. [ABSTRACT FROM AUTHOR]

The authors investigate equilibrium properties of a simple model of hydrophobic polymer in aqueous solution by means of dynamic Monte Carlo simulations. The solvent is described by a simplified two-dimensional model, defined on a triangular lattice, which has been previously shown to account for most thermodynamic anomalies of pure water and of hydrophobic solvation for monomeric solutes. The polymer is modeled as a self-avoiding walk on the same lattice. In this framework, the degrees of freedom of water are taken into account explicitly, and in principle there is no need to introduce effective self-contact interactions for the polymer in order to mimic the hydrophobic effect. In certain conditions, the authors observe low-temperature-induced swelling, i.e., expansion of the polymer globule upon decreasing temperature. The authors discuss the relationship between this phenomenon and the anomalous properties of the solvent. [ABSTRACT FROM AUTHOR]

[Display omitted] • The addition of the polymer improved the hydrophobicity of the polyurethane surface. • PAM and PEO combine directly with hydrophobic surfaces and form a cover layer. • XG and GG form aggregates with water first and then transfer to hydrophobic surfaces. • PAM-polyurethane hydrophobic surface has a better synergistic effect than others. The drag reduction synergy of four types of high-molecular polymers, namely polyacrylamide, poly(ethylene oxide), xanthan gum, and guar gum, with polyurethane hydrophobic surfaces, was investigated by both experiments and molecular simulations. The synergistic mechanisms of polymers and hydrophobic surfaces were revealed using Monte Carlo and molecular dynamics simulations in terms of interfacial interactions between polymers and water molecules, intermolecular interactions, and the adsorption conformation of polymers on hydrophobic surfaces. The addition of the polymer improved the hydrophobicity of the polyurethane surface, with flexible polymers having a more substantial effect than rigid polymers, according to both simulations and contact angle experiments. Furthermore, based on the transient configuration of polymer and water molecules moving on the hydrophobic surface, the kinetic process is divided into three stages: water molecule aggregation, water molecule-induced deformation, and polymer extension on the hydrophobic surface. Meanwhile, PAM and PEO combine directly with hydrophobic surfaces and form a cover layer with water molecules, whereas XG and GG prefer to form aggregates with water molecules first and then transfer to hydrophobic surfaces. The PAM-polyurethane hydrophobic surface, in particular, has a better synergistic effect than others, and its synergistic mechanism is related to the larger radius of gyration, stronger interaction with water molecules, and higher stability of the drag reduction system. [ABSTRACT FROM AUTHOR]

Most of the super hydrophobic paper surfaces prepared at present will change the original properties of the paper and can not be used for oil-water separation continuously. There is not yet much systematic research on super hydrophobic modification of paper-based materials. The use of polymers and inorganic fillers for synergistic modification is also relatively rare. In this paper, fluorine-containing epoxy polymer P(GMA- r -DFMA) and KH550 modified nano-SiO 2 were mixed to obtain an organic-inorganic hybrid super hydrophobic solution, which was chemically cross-linked to the surface of paper fibers to form a micro- and nano-thin coating to construct a super hydrophobic surface, but the original properties of the paper remain unchanged. The optimal parameters (polymer concentration, soaking time, drying time, drying temperature) for building super hydrophobic surface on paper were explored, and the optimal conditions are the polymer concentration of 7 mg/mL, soaking time of 5 h, drying time of 6 h, drying temperature of 100 °C. Under the optimum conditions, the water contact angle of the modified paper surface is 164 ± 2o and the water rolling angle is 5 ± 2o. The surface of the super hydrophobic modified paper contaminated with toner can be self-cleaned by water droplets. Compared with the unmodified paper, the whiteness, smoothness and glossiness of the surface of the super hydrophobic modified paper have not changed greatly. When the oils were n -hexane, n -octane and trichloromethane, the oil-water separation efficiency of the modified paper could reach 99.9 %, 99.9 % and 98 %, and the effects were stable. Super hydrophobic modified paper in water formed a large number of bubbles on its surface, resulting in silver mirror phenomenon. SEM results showed that the pore structure of the paper was not changed after modification. The surface of the original paper fiber is very smooth, but the surface of the super hydrophobic modified paper fiber has a large number of micro and nano protrusions. • Fluorine epoxy polymer and nano-SiO 2 were used to construct super hydrophobic paper, meanwhile original properties unchanged. • WCA is 164±2o and WRA is 5±2o. The super hydrophobic paper contaminated with toner can be self-cleaned by water droplets. • The whiteness, smoothness and glossiness of the super hydrophobic modified paper have not changed greatly. • The separation efficiency of the modified paper could above 98% when the oils were n -hexane, n -octane and trichloromethane. [ABSTRACT FROM AUTHOR]

Fluorinated ethylene propylene (FEP) vessels are of significant interest for therapeutic cell biomanufacturing applications due to their chemical inertness, hydrophobic surface, and high oxygen permeability. However, these properties also limit the adhesion and survival of anchorage-dependent cells. Here, we develop novel plasma polymer coatings to modify FEP surfaces, enhancing the adhesion and expansion of human mesenchymal stromal cells (hMSCs). Similar to commercially available tissue culture polystyrene vessels, oxygen-rich or nitrogen-rich surface chemistries can be achieved using this approach. While steam sterilization increased the roughness of the coatings and altered the surface chemistry, the overall wettability and oxygen or nitrogen-rich nature of the coatings were maintained. In the absence of proteins during initial cell attachment, cells adhered to surfaces even in the presence of chelators, whereas adhesion was abrogated with chelator in a protein-containing medium, suggesting that integrin-mediated adhesion predominates over physicochemical tethering in normal protein-containing cell seeding conditions. Albumin adsorption was more elevated on nitrogen-rich coatings compared to the oxygen-rich coatings, which was correlated with a higher extent of hMSC expansion after 3 days. Both the oxygen and nitrogen-rich coatings significantly improved hMSC adhesion and expansion compared to untreated FEP. FEP surfaces with nitrogen-rich coatings were practically equivalent to commercially available standard tissue culture-treated polystyrene surfaces in terms of hMSC yields. Plasma polymer coatings show significant promise in expanding the potential usage of FEP-based culture vessels for cell therapy applications. [Display omitted] [ABSTRACT FROM AUTHOR]

The conformation and titration curves of weak (or annealed) hydrophobic polyelectrolytes have been examined using Monte Carlo simulations with screened Coulomb potentials in the grand canonical ensemble. The influence of the ionic concentration pH and presence of hydrophobic interactions has been systematically investigated. A large number of conformations such as extended, pearl-necklace, cigar-shape, and collapsed structures resulting from the subtle balance of short-range hydrophobic attractive interactions and long-range electrostatic repulsive interactions between the monomers have been observed. Titration curves were calculated by adjusting the pH-pK0 values (pK0 represents the intrinsic dissociation constant of an isolated monomer) and then calculating the ionization degree α of the polyelectrolyte. Important transitions related to cascades of conformational changes were observed in the titration curves, mainly at low ionic concentration and with the presence of strong hydrophobic interactions. We demonstrated that the presence of hydrophobic interactions plays an important role in the acid-base properties of a polyelectrolyte in promoting the formation of compact conformations and hence decreasing the polyelectrolyte degree of ionization for a given pH-pK0 value. [ABSTRACT FROM AUTHOR]

We calculate thermodynamic quantities of hydrophobic-polar (HP) lattice proteins by means of a multicanonical chain-growth algorithm that connects the new variants of the Pruned-Enriched Rosenbluth Method and flat histogram sampling of the entire energy space. Since our method directly simulates the density of states, we obtain results for thermodynamic quantities of the system for all temperatures. In particular, this algorithm enables us to accurately simulate the usually difficult accessible low-temperature region. Therefore, it becomes possible to perform detailed analyses of the low-temperature transition between ground states and compact globules. © 2004 American Institute of Physics. [ABSTRACT FROM AUTHOR]

Studies the phase behavior of single homopolymers in a simple hydrophobic/hydrophilic off-lattice model with sequence independent local interactions. Monte Carlo methods used in the study; Dynamics of the algorithms; Measurement of specific heat and bond-bond correlation function.

Poly(methyl methacrylate) (PMMA) nanoparticles with a sensitive CO2‐responsive hydrophilic/hydrophobic surface that confers controlled dispersion and aggregation in water were prepared by emulsion polymerization at 50 °C under CO2 bubbling using amphiphilic diblock copolymers of 2‐dimethylaminoethyl methacrylate (DMAEMA) and N‐isopropyl acrylamide (NIPAAm) as an emulsifier. The amphiphilicity of the hydrophobic–hydrophilic diblock copolymer at 50 °C was triggered by CO2 bubbling in water and enabled the copolymer to serve as an emulsifier. The resulting PMMA nanoparticles were spherical, approximately 100 nm in diameter and exhibited sensitive CO2/N2‐responsive dispersion/aggregation in water. Using copolymers with a longer PNIPAAm block length as an emulsifier resulted in smaller particles. A higher concentration of copolymer emulsifier led to particles with a stickier surface. Given its simple preparation and reversible CO2‐triggered amphiphilic behavior, this newly developed block copolymer emulsifier offers a highly efficient route toward the fabrication of sensitive CO2‐stimuli responsive polymeric nanoparticle dispersions. © 2019 Wiley Periodicals, Inc. J. Polym. Sci., Part A: Polym. Chem. 2019, 57, 2149–2156 [ABSTRACT FROM AUTHOR]

An original method of obtaining hydrophobic surfaces from blends of immiscible polymers by creating porosity through removing one of the components of the blend is considered. Polymethylpentene and polyisobutylene are used as polymers. The first polymer, which is crystallizable, is the basis for the creation of a coating, while the second polymer is amorphous and easily and completely extractable from the blend with heptane. Blends containing from 5 to 55% polyisobutylene are studied. They are characterized by the non-Newtonian behavior and low viscosity that does not reach the viscosity of the polymer matrix owing to the interlayer slip. Removing the amorphous polymer from the blend makes it possible to attain a surface porosity of 45%, which acts as a fractal surface roughness. As a result, the contact angle of polymethylpentene film with water and ethylene glycol increases from 108° to 137° and from 78° to 132°, respectively. The low viscosity of the blends provides their easy processing, including the method of 3D printing, in order to create chemically resistant hydrophobic coatings. [ABSTRACT FROM AUTHOR]

In this paper, the hydrophobic polymer surface with regular and controllable micro-textured structures was effectively and rapidly fabricated by micro-injection molding using a novel micro-textured mold machined by wire electrical discharge machining (WEDM). The phase constitutions of smooth and micro-textured mold surfaces were compared along with machined surface roughness of molds. The surface topographies of micro-textured molds and micro-injection molded polymers were characterized. The machining accuracy of WEDM for micro-textured mold and the replication rate of micro-injection molding for micro-textured polymer were calculated and analyzed. The wetting behaviors of smooth and micro-textured polymer surface were investigated together with the static contact angle and contact angle evolution versus time. The experimental results show that the maximum contact angle on the micro-textured polymer surface can reach to 127.5°, which was improved by about 71.6% compared with smooth polymer surface. It is shown that the highest machining accuracy of mold and the maximum replication rate of micro-injection molding can reach to 0.153% and 99.455%, respectively. [ABSTRACT FROM AUTHOR]

A multilayer plasma polymer coating was deposited on small glass discs and afterwards treated with ultra violet radiation through a patterned mask to generate a micro-structured substrate with an alternating hydrophilic/hydrophobic surface. The substrate was then immersed in a mother liqueur of the porous, functional material Metal-Organic Framework Ulm-4 (MFU-4) to preferentially grow crystals on the hydrophilic areas of the film. X-ray diffraction and electron microscope analysis showed the formation of MFU-4 single crystals. • Chemically robust micro-structured, multilayer plasma polymer coating • Hydrophobic polytetrafluoroethylene-like coating deposited from trifluoromethane • Spatially directed crystal growth of a porous functional material [ABSTRACT FROM AUTHOR]

It was presented the data on the thicknesses of the adsorbed polymer layer, which were obtained for copper phthalocyanine (CuPc) pigment dispersions under ultrasonic processing conditions. The thicker adsorption layers, which are observed in ultrasound systems, confirm the fact that the activation of the surface of the pigment occurs under the action of ultrasonic energy. The course and efficiency of adsorption of the polymer onto the pigment surface were quantified by electrokinetic measurements of the amplitude of sound (EIAZ). It became possible to obtain a more detailed picture of the pigment-polymer interactions and the adsorption mechanism of the copolymer based on the data on the dynamic mobility, obtained as a result of electrokinetic measurements of the amplitude of the sound. For aqueous dispersions of CuPc, stabilized with a copolymer of poly (acrylic acid) -poly (isobornyl acrylate) (PiBA-PAA), it was established the saturation concentrations of polymeric surfactant. Thus, the ultrasonic treatment allows to obtain stable, highly dispersed pigment suspensions with a modified pigment surface, which opens up new prospects for a more effective change in the surface of the pigment. [ABSTRACT FROM AUTHOR]

The main aim of this investigation was to study the interaction of cationised xylans as antimicrobial substances with poly(ethylene terephthalate) (PET) model films, prepared by spin coating. A quartz crystal microbalance (QCM-D) with dissipation monitoring was applied as a nanogram sensitive balance to detect the amount of adsorbed cationised xylans. The xylan adsorption onto PET model films was studied as a function of pH and ionic strength. To improve the adsorption, positively charged polyethylenimid (PEI) and negatively charged polyvinyl-sulfonic acid (PVSA), as sodium salt, were applied as anchoring polymers. Surface free energies and hydrophilic/hydrophobic properties of surfaces were monitored by goniometry. Cationised xylans favourably deposited at pH 5, where beside electrostatic, physical interactions are possible, and adsorption may be driven by entropy gain. Higher ionic strengths of solutions also improved adsorption, due to the lower water solubilities of xylans. When intermediate layers of chosen anchoring polymers were applied on the PET surfaces, the binding of xylans as well as their coating durability were improved. Surface modifications presented in this work, provided important information regarding the adsorption/desorption phenomena between antimicrobial cationised xylans and synthetic PET surfaces. The latter is of great interest, when composing hydrophilic and antimicrobial PET surfaces for medical applications. [ABSTRACT FROM AUTHOR]

Mixing precursors of lead(ii) polymers with those of lead bromide-based nanoparticles (CH3NH3PbBr3 perovskites or PbBr2), at room temperature and in the presence of cyclohexanemethylammonium bromide, generated colloidal nanocomposites which, when deposited on a hydrophobic surface led to long, one-dimensional, ordered and well-defined architectures. [ABSTRACT FROM AUTHOR]

Graphical abstract The self-cleaning process for (right) bare PC and (left) PC coated sample. Highlights • GPTMS-silica nano-hybrid coatings were immobilized on PC substrates. • Nano-hybrid coating enhanced the transmission of the PC substrates. • Nano-hybrid coating increased the WCA of the PC surface from 75° to 110° degrees. Abstract In this research, GPTMS-silica nano-hybrid coatings were immobilized on polycarbonate (PC) substrates by a sol-gel method. Perfluorooctyl-trichlorosilane (PFTS) was utilized to modify the prepared nano-hybrid coating surface. The modified nano-hybrid coatings were characterized by Field Emission Scanning Electron Microscope (FE-SEM), Energy Dispersive X-ray Spectrometry (EDS), atomic force microscopy (AFM), attenuated total reflectance Fourier transform infrared spectroscopy (ATR-FTIR), UV–vis-NIR spectrophotometer, and water contact angle analyzer methods. In addition, the self-cleaning properties of the nano-hybrid coatings were investigated. The results indicated that the formation of the nano-hybrid film improved the hardness and transmittance of the PC substrate. FE-SEM image indicated the formation of the crack free coating on the PC substrate. In addition, the modified nano-hybrid coating displays hydrophobicity (CA, 110°) and is very efficient at removing dust through water droplets. [ABSTRACT FROM AUTHOR]

Highlights • Fluorinated triazine ultraviolet absorbers were synthesized. • FT-UVA with surface enrichment property. • Hydrophobicity. • Simulation of dynamic process. Abstract Most of the polymer coatings are directly exposed to sunlight, leading to serious degradation on their surfaces. Functional triazine ultraviolet absorber (FT-UVA) with surface enrichment property was synthesized. The surface enrichment property of FT-UVA in coating surfaces was investigated using X-ray photoelectron spectroscopy (XPS) and attenuated total reflection Fourier-transform infrared spectrometry (ATR-IR). Contact angle measurements suggest that the enrichment of FT-UVAs on coating surface yielded a hydrophobic film. The effective protection of FT-UVA for PVC coating was investigated by artificial accelerated aging test. The calculation of dynamic process was conducted to gain insights into the surface enrichment mechanism of FT-UVA in coating. [ABSTRACT FROM AUTHOR]

A novel surface-active polymer (PCPAM) was synthesized by free-radical polymerization of acrylamide (AM), 2-acrylamido-2-methyl propane sulfonic acid (AMPS) and surfmer (ACP) which was previously prepared by reacting Nonaphenol polyethyleneoxy ether-10 (OP-10) and allyl chloride. The structure of PCPAM was characterized by FT-IR, 1H-NMR, GPC and TGA. In addition, the self-assembly properties of the copolymer were studied with viscosimetry and fluorescence probe method. Moreover, the activity of PCPAM solution was examined with surface tension, IFT and emulsifying ability. Results indicated that, the solution viscosity proportionally increased with PCPAM concentrations, leading in the formation of a three-dimensional network with surface activity and thermal stability, and the CAC of PCPAM was about 1.5 g/L, PCPAM can reduce the interfacial tension between crude oil and water, the IFT value was about 0.029 mN/m when the concentration of PCPAM beyond CAC and have good ability to form stable emulsions. Furthermore, the core flooding experimental demonstrated that the oil displacement efficiency of PCPAM increased by about 17.4%, which is better than 13.87% and 15.55% based on HPAM flooding and HPAM/surfactant flooding, respectively. All of these properties indicate that the PCPAM was an excellent chemical for chemical enhanced oil recovery. [ABSTRACT FROM AUTHOR]

Abstract Transparent materials such as glasses and some polymers play an essential role in our daily life. Indeed, it is well known that their application in mirrors, windows, automobile windshields, and eyewear make our day-to-day activities more comfortable. These examples aside, many more can also be found in several spheres of human activity, including such sectors as diverse and distinct as the medical, photovoltaic and food industry fields. Unfortunately, due to the unavoidable condensation of water vapor on solid surfaces, these materials undergo fogging under normal operating conditions. More than a mere nuisance, this naturally occurring phenomenon adversely affects their optical performance as it lowers the light-transmitting capability and often gives rise to esthetical, hygienic, and safety concerns. In this context, research in the field of anti-fogging technology has attracted growing interest, particularly in recent years, for numerous potential applications. In this review, recent developments in the design and manufacturing of anti-fogging surfaces are described in detail, beginning with the fogging mechanism in terms of nucleation and growth of water drops. Anti-fogging strategies explored thus far and mainly focusing on hydrophilic and hydrophobic surfaces are then extensively described. Finally, based on current research in this promising field, future trends and prospects for their effective implementation are presented. [ABSTRACT FROM AUTHOR]

Graphical abstract Highlights • Vinyl pyrrolidone was polymerized by photochemical RAFT in absence of external radical source. • Copolymers for post-polymerization modification were obtained by addition of vinyl acetate. • The ice recrystallisation inhibition activity with hydrophobic side chains was evaluated. Abstract Antifreeze, ice binding and ice nucleating proteins modulate the formation and growth of ice in biological systems, enabling extremophiles to survive in sub-zero temperatures. A common feature is their rigidity, and segregated hydrophobic and hydrophilic domains. It has been demonstrated that increased hydrophobicity in rigid, facially amphipathic, synthetic polymers enhances ice recrystallisation inhibition (IRI) activity, but has not been evaluated in flexible systems. Here photochemical RAFT/MADIX polymerisation is used to obtain well-defined poly(N -vinyl pyrrolidone), PVP, copolymers to probe the impact of hydrophobicity on ice recrystallisation inhibition in a fully flexible polymer system, to increase the understanding on how to mimic antifreeze proteins. It is observed that PVP homopolymers have only very weak, molecular weight dependent, IRI and that hydrophobic co-monomers give very modest changes in IRI, demonstrating that the spacial segregation of 'philicities' is crucial, and not just the overall hydrophobic content of the polymer. These results will help design the next generation of IRI active polymers for cryopreservation applications as well as aid our understanding of how biomacromolecules can inhibit ice growth. [ABSTRACT FROM AUTHOR]

Highlights • Water drops on hydrophobic expanded polymer mats were exposed to the air flow. • The effects of pore sizes, mat thicknesses, and wetting properties on drop motions were studied. • Experimental data were fitted to new correlations to estimate the lowest Reynolds number that initiates the drop motion and the drag coefficient of drop movement on the mat surface. Abstract Hydrophobic expanded polymer mats are used in a wide range of industries for many purposes. Their relatively low cost, availability in a wide range of polymer materials, and consistency of pore size distribution are advantageous for some applications such as the separation of liquid drops from gas streams. When fabricated of a non-wetting material, liquid drops tend to stay on one side of the mat and can move across the mat surface due to drag of the gas flow. The rate of movement of drops on the surface can affect the rate of coalescence, the drop size, the loading of drops on the surface of the mat, and ultimately the effectiveness of the mat to separate the drops from a gas stream. In this work the movements of water drops on the surfaces of expanded polymer mats due to tangential air flow are observed to determine the effects of mat material properties and geometrical characteristics, drop dimensions and air flow conditions. A correlation for a drag coefficient of drop movement on the mat surface is developed. A second correlation for the minimum Reynolds number of the gas to initiate the movement of drop on the surface of the mat is also developed. Graphical abstract Image, graphical abstract [ABSTRACT FROM AUTHOR]

[Display omitted] • Development of substrate-independent coatings with controllable surface chemistry. • HMDSO plasma polymerization on PCL-PLGA nanofibers without fiber damage. • APTES silanization of HMDSO-based coatings makes primary amine containing surfaces. • Improvement in cell-material interactions by APTES silanized coatings on nanofibers. Surface modification of hydrophobic nanofibers (NFs) to introduce cell-interactive chemical functionalities remains a challenge in biomedical applications. This study presents a novel three-step plasma-based method for synthesizing coatings with improved chemical selectivity compared to conventional plasma polymers. The process involved hexamethyldisiloxane (HMDSO) plasma polymerization followed by helium plasma activation, both performed in a medium-pressure dielectric barrier discharge. Scanning electron microscopy analysis demonstrated that the plasma-based steps did not cause damage to the NFs. X-ray photoelectron spectroscopy (XPS) and water contact angle measurements revealed the formation of a hydrophilic silanol-rich layer after HMDSO plasma polymerization and helium plasma activation. In the third step, (3-aminopropyl)triethoxysilane (APTES) was grafted onto the plasma polymer to introduce primary amine groups onto the surface, as confirmed by XPS. Although the APTES-based layer exhibited partial removal when exposed to aqueous environments, a stable aminated layer remained on the NF surface, which significantly enhanced Schwann cell responses compared to untreated and HMDSO-based coated NFs. This enhancement was confirmed through fluorescent imaging using live-dead staining, immunostaining, and 3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyl-2H-tetrazolium bromide (MTT) assay. These coatings with a high selectivity in their chemical functionality (amines, or other functionalities via silanization agent selection), offer a promising surface functionalization approach for tissue engineering scaffolds. [ABSTRACT FROM AUTHOR]

[Display omitted] • The degree of polymerization significantly affects the interaction of PEO with the surface. • Surface type has a bigger impact on water adsorption than polymer type but less than DP. • The interaction between PAM and the surface is strongly influenced by temperature. • The adsorption of PEO on surfaces depends mainly on the chain's deformation. • For XG-TDI and GG-HDI systems, van der Waals has the most impact on the interaction. Hydrophobic surfaces and polymer additives are both desirable for effectively reducing drag when carrying fluids, and the synergy of these two has naturally attracted a great deal of attention. The interaction between a polyurethane surface with different raw material compositions and drag-reducing polymers such as polyacrylamide (PAM), polyethylene oxide (PEO), xanthan gum (XG), and guar gum (GG) was investigated using molecular simulation methods such as molecular dynamics and Monte Carlo. The effects of polymerization degree (DP), temperature, and water molecule adsorption on the interaction were further examined. The findings demonstrate that rigid polymers (XG and GG) have a higher capacity for adsorption on the polyurethane surface than do flexible polymers (PAM and PEO). Furthermore, the DP clearly affects the PEO interacts with surfaces. Under a fixed water molecule load, the influence of surface type on water molecule adsorption ability is greater than that of polymer type but weaker than that of DP. Temperature clearly influences the interaction of PAM and surfaces, whereas PEO has the opposite effect. Additionally, PEO's deformation energy contributes more to the adsorption energy than others, whereas PAM's adsorption energy is higher because its longer molecular chains occupy the adsorption site on the surface. [ABSTRACT FROM AUTHOR]

For proper biofilm formation, bacteria must have mechanisms in place to sense adhesion to surfaces. In Escherichia coli, the CpxAR and RcsCDB systems have been reported to sense surfaces. The CpxAR system is widely considered to be responsible for sensing attachment, specifically to hydrophobic surfaces. Here, using both single-cell and population-level analyses, we confirm RcsCDB activation upon surface contact, but find that the CpxAR system is not activated, in contrast to what had earlier been reported. Thus, the role of CpxAR in surface sensing and initiation of biofilm formation should be reconsidered. [ABSTRACT FROM AUTHOR]