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Hydroxyapatite (HAp)‐polymer composite materials are of interest for materials that interface with or substitute bone tissue. HAp nanoparticles (length 290 nm, width 56 nm) synthesized by a wet chemical method were incorporated (5 wt%) into natural rubber latex (NRL), poly lactic acid (PLA) and NRL/PLA (75/25) solvent cast films using three different methods: dry nanoparticles; a dispersion prepared from dry nanoparticles; a dispersion prepared through solvent exchange. Common to all composite materials were an improvement in the contact angle by 10%–13% and a reduction in the elongation at break from 430% to 330%–370%. Furthermore, the method of HAp incorporation influenced the properties of the material with the use of dioxane suspension improving the homogeneity of the films as evidenced from visual appearance and SEM. This led to slower water uptake and higher thermal stability with a shift in the PLA melting peak from 296°C to 334°C when compared to pure polymer and composites with poorly dispersed particle. [ABSTRACT FROM AUTHOR]

Polytetrafluoroethylene (PTFE) and its composite films are difficult to bond with other materials due to the molecular chain structure of PTFE, which limits the application in the electronic fields. In this work, surface modification of PTFE/SiO2 composite films are realized through the polydopamine (PDA) deposition. The chemical and morphological results exhibit that PDA is successfully deposited on the surface of the PTFE/SiO2 films. The deposition of PDA changes the polarity and wettability of PTFE/SiO2 composite films. Thus, a significant development in the adhesive performance is obtained, and the peel strength increases from 0.34 to 0.42 N/mm. Moreover, the dielectric property and mechanical performance of the films are maintained. After immersed in 3.0 g/L DAH solution for 24 h, the dielectric constant of the composite films is still as low as 2.44 (10 GHz), and the dielectric loss decreases from 0.002 to 0.00035 (10 GHz). The tensile strength and elongation at break are barely reduced. Therefore, the surface deposition of PDA is considered as a profound modification for the PTFE/SiO2 films in the electronic industry. [ABSTRACT FROM AUTHOR]

Various strategies have been developed to fabricate superhydrophobic surfaces with the guidance of adding rough micro‐nano structure and decreasing surface energy. However, it is still a challenge to prepare a superhydrophobic coating with multifunction, eco‐friendliness, and broad applicability to substrates. The mussel‐inspired polydopamine (PDA) possessing superior material‐independent adhesion was considered as the promising candidate material. Herein, a hierarchical superhydrophobic PDA coating was fabricated on Cu substrate via a facile self‐assembly method. Thanks to PDA's self‐roughening and self‐adhesive effects, the coating obtains sufficient surface roughness and good interface adhesion. The superhydrophobic coating exhibits excellent self‐cleaning performance and enhanced corrosion resistance based on the surface wettability. Moreover, it possesses the additional functions of UV resistance and self‐healing, inheriting from the PDA coating. PDA and the surface modifier are nontoxic, biodegradable, and eco‐friendly. Our findings indicate that PDA can be used as an independent structural coating with multiple functions of corrosion protection, UV resistance, and superhydrophobic properties. [ABSTRACT FROM AUTHOR]

The addition of inorganic particles can endow polymer matrices with different new features, thereby realizing an optimization to the structural and functional properties of composite. The overall properties of composites are greatly influenced by both fillers dispersion and fillers‐polymer interfacial interaction. However, to simultaneously improve these mentioned two issues is still a critical challenge in the field of polymer‐based nanocomposite. Herein, a typical core‐shell structured mesoporous silica‐coated silica (SiO2@mSiO2) construction was successfully synthesized by using a bi‐phase method. The SiO2@mSiO2 filled polyethylene (PE) nanocomposite was fabricated through a precisely controlled melt‐mixing approach. Benefiting from the additional mesoporous SiO2 shell, both the dispersion of SiO2@mSiO2 and the SiO2@mSiO2‐PE matrix interfacial interaction are improved. Moreover, the stress–strain behavior, temperature‐dependent mechanical property, thermal stability, and electrical insulating property of SiO2@mSiO2/PE composite were studied in detail. It is found that SiO2@mSiO2 core‐shell nanoparticles are capable of not only making a balance between the strength and toughness of the PE‐based composite, but also improving the thermal stability of the composite. In addition, the SiO2@mSiO2/PE composite exhibited an enhanced breakdown strength (256.4 MV·m−1) when filled with as small as 1 wt% SiO2@mSiO2, which is 108% higher than neat PE. All these optimized features are attributed to the well‐designed core‐shell structure. These experimental results provide a promising way to design and fabricate future advanced composite with excellent structural and functional properties in the future. [ABSTRACT FROM AUTHOR]

The paradox of obtaining dielectric elastomers (DEs) with both low modulus and high‐dielectric properties has long been puzzling researchers in this field. To solve this problem, a preliminary attempt is made here by solution compounding polyphenol nanoparticles modified multiwalled carbon nanotube (PNs@MWCNT) with polydimethylsiloxane (PDMS) to obtain PDMS based DEs with excellent electromechanical properties. The PNs layer can improve the interfacial interaction between MWCNT and PDMS probably through interfacial hydrogen bonding, thus improving the dispersion of PNs@MWCNT in PDMS. Compared with pure MWCNT filled PDMS nanocomposites, despite the hardening effect brought by the filler network, a softening effect (i.e., decreased cross‐linking) by the finer filler‐dispersion enhances in PNs@MWCNT/PDMS, resulting in lower moduli. Meanwhile, the as‐prepared PNs@MWCNT/PDMS composites exhibit high permittivity, low‐dielectric loss and high‐breakdown strength. Finally, the PNs@MWCNT/PDMS nanocomposites show excellent electromechanical properties with a largest actuated strain of 7.4% at a breakdown strength of 13.1 kV/mm, which is 2.2 times that (3.3%@13.3 kV/mm) of MWCNT/PDMS and 3.9 times that (1.9%@18.8 kV/mm) of neat PDMS. [ABSTRACT FROM AUTHOR]

Poly(phenylene sulfide) (PPS) is an advanced thermoplastic and widely used in industrial applications requiring high performance. Research on improving the surface properties of PPS is still ongoing and a detailed surface free energy (SFE) knowledge of this polymer is necessary for its applications related to surface wettability. In this study, wettability characteristics of PPS were evaluated by SFE calculations. For this purpose, the apparent contact angles of nine different test liquids having various surface tensions were measured on the PPS surface by the sessile drop method. After that, the dispersive and polar components of SFE were calculated using geometric (Owens and Wendt's method) and harmonic (Wu's method) mean approaches. The Lifshitz‐van der Waals, acidic and basic components of SFE were calculated using van Oss‐Chaudhury‐Good method. Additionally, the surface tension values of PPS were also determined by equation of state, Zisman's critical surface tension and Fowkes' approaches. In the present study, the effects of calculation methods and selected liquid pairs on SFE parameters were systematically investigated. It was found that selected liquid pairs and calculation methods affected the SFE considerably. The reasons for this were examined and the SFE components of PPS was compared with some common polymers for better evaluation. [ABSTRACT FROM AUTHOR]

Effects of subphase temperature and pH on the interfacial behavior of two strong amphiphilic cationic diblock polyelectrolytes, quaternized poly(2‐[dimethylamino]ethyl methacrylate)‐block‐poly(lauryl methacrylate) (qPDMAEMA‐b‐PLMA), were studied by the Langmuir film balance technique for the first time. The morphologies of their Langmuir–Blodgett (LB) films were studied by atomic force microscopy. At the air/water interface, surface micelles with hydrophobic PLMA cores and hydrophilic qPDMAEMA coronas form. With the increase of temperature, the condensed surface pressure‐molecular area isotherms move to large area (right shift). The higher the temperature, the more obvious the isotherm shifts to the right. At low temperature, the isotherms of the two copolymers are almost respectively overlapped under different subphase pH conditions. At high temperature, however, the isotherms of the two copolymers show some subphase pH dependence. All initial LB films obtained at different subphase conditions exhibit isolated circular micelles. Under different subphase pH conditions, the diameters of the micelle cores in the two copolymers' LB films obtained at low temperature are close but larger than those at high temperature, which phenomenon is first reported. This is probably due to the relatively lower mobility of polymer individual chains at low temperature, resulting in their higher local surface concentration and larger aggregation. [ABSTRACT FROM AUTHOR]

Reduction of calcium carbonate (CaCO3) scale formation on the equipment surface is essential in a wide variety of industrial fields. In this work, polydopamine/polytetrafluoroethylene (PDA/PTFE) coating prepared by the simple immersion on stainless steel (SS) surfaces was developed to suppress the CaCO3 scale adhesion. The PDA/PTFE‐coated surface showed the higher hydrophobicity (water contact angle = 133.50°) and lower surface free energy (11.92 mN/m) than the stainless‐steel surface. The scale inhibiting rate of the coated surface was up to 76.8% after 12‐hour immersion in the CaCO3 solution in comparison with the untreated SS. More bubbles were observed on the PDA/PTFE‐coated surfaces, and the number of bubbles increased with increasing solution temperature leading to less area for the scale adhesion. As a result, the PDA/PTFE coated surfaces have the higher antiscale ability at the higher solution temperature. Furthermore, the stripping and electrochemical corrosion tests demonstrated that the PDA/PTFE coating has the better stability and anticorrosion ability. The PDA/PTFE coating with the superior properties has potential application for the long‐lasting reduction of the scale formation. [ABSTRACT FROM AUTHOR]

In this work, a new AC@Catechol/PEI adsorbent was prepared via the copolymerization of catechol and polyethyleneimine (PEI) onto pretreated commercial activated carbon (AC). It achieved a high adsorption capacity of 411.52 mg/g for the anionic dye Congo red (CR), which was approximately 7 times that of pretreated AC without modification. In bath adsorption experiment, 1 g of adsorbent was used to treat 4 L of 100 mg/L CR solution, resulting in 98.5% CR removal. In addition, the prepared AC@Catechol/PEI adsorbent exhibited highly efficient CR competitive adsorption against SO42− ions and cationic malachite green dye. The adsorption mechanism was mainly attributed to electrostatic interactions, hydrogen bonding, and π–π stacking. Catecholamine modification greatly improved the adsorption capacity and adsorption selectivity of commercial AC for CR dyes. This low‐cost adsorbent may have broad prospects for the removal of anionic dyes in wastewater. [ABSTRACT FROM AUTHOR]

In this study, carbon fiber (CF)/epoxy (EP) composites are toughened with 3D‐printed poly‐ε‐caprolactone (PCL) grid structures which are produced by fused deposition modeling at three different areal weight densities and place between dry plain‐weave carbon fabrics prior to resin infusion. Three‐point bending, Mode‐I fracture toughness, interlaminar shear strength (ILSS), and Charpy impact tests are carried out on the prepared composite specimens. The results show that the PCL interlayers can enhance Mode‐I fracture toughness up to seven times (693%). The main toughening mechanism is the crack bridging due to the formation of PCL fibrils. It is shown that there is a quadratic relationship between the amount of PCL and Mode‐I fracture toughness improvement. The thermal healing efficiencies (η) for the first and second healing of PCL reinforced composites are determined as 44.1% and 28.2%, respectively. DMA results indicates that the tanδ values are increased almost 10 times with the addition of PCL interlayers. The flexural properties are decreased due to the reduced fiber volume fraction, higher void content, and plasticization effect of PCL interlayers. [ABSTRACT FROM AUTHOR]

Flexible electronic fabrics urgently need to solve the problem of adhesion between the conductive layer and the fabric substrates. Inspired by phenamine bionics, we designed and fabricated copper nanoparticle conductive network/nylon 6 woven fabric (CNNs/NWF) wearable heaters through rapid co‐deposited of tannic acid and polyethyleneimine (PEI) by using CuSO4/H2O2 as a trigger. The grafted TA/PEI interface is capable of anchoring on the fabric surface via covalent and non‐covalent bonds on the one hand and providing an ideal platform to absorb and reduce catalyst Ag+ to facilitate subsequent electroless deposition on the other. Furthermore, the electrical heater could rise temperature from 14.6 to 152.6°C within 90 s under 1.5 V voltage, better than that of recently reported literature. The heater had a splendid conductivity (sheet resistance R0 ≈ 0.0086 Ω sq−1) and remain stable after 1000 bending cycle tests (normalized resistance R/R0 ≈ 2.5). Furthermore, the heater could meet 50 standard washing tests, satisfying the essential needs of the wearable devices. The deviation between the simulated data and the measured data was no more than 10% by the simulation of the finite elemental analysis. This study might provide a viable source for wearable heating devices. [ABSTRACT FROM AUTHOR]

Recently, the research of blending anti‐aging modification of nitrile butadiene rubber (NBR) has been widely reported, but the surface effect in the rubber aging process has been obviously ignored. Starting from the surface microstructure design, the construction of surface protection barrier may be a new anti‐aging way. In this paper, the surface superhydrophobic NBRsurf‐polydopamine (PDA)‐(SiO2‐g‐PFOMA) is prepared through a ordered modification of two‐step physical deposition to NBR with PDA and SiO2 grafted with Perfluorooctylmethacrylate (SiO2‐g‐PFOMA). By comparing the mechanical properties before and after aging, it is found that the DA surface pretreatment significantly improves the NBR thermo‐oxidative aging. On this basis, surface superhydrophobic SiO2‐g‐PFOMA microstructure has set up to further prevents NBR from the attack of corrosive media such as acid, alkali, salt and water. After aging in HCl solution at 90°C for 96 h, the fracture strength, elongation and aging coefficient of NBRsurf‐PDA‐(SiO2‐g‐PFOMA) compared with unmodified NBR(KB) were increased by 2.28 MPa, 48.76% and 0.18, respectively. This work can offer an surface anti‐aging technology to NBR. [ABSTRACT FROM AUTHOR]

Corrosion and biofouling are the most severe threats to the security of engineering equipment and materials. Oil‐impregnated gel (OIG) is a promising coating material for both corrosion protection and biofouling prevention. Unfortunately, OIGs are prone to damage due to their weak mechanical strength, and most of the reported OIGs are irreversibly cross‐linked through covalent bonds. To meet the great demand of self‐repairable OIGs for their durable applications, we develop a self‐repairable OIG coating based on the reversible sol‐gel process of styrene‐isoprene‐styrene triblock copolymer (SIS) and n‐hexadecane in the current work. The rheological properties of SIS/hexadecane were investigated by a rotary rheometer, which revealed the reversible sol‐gel transition during the cooling process as well as the gelation temperature with the SIS concentration above 2%. Owing to the dynamic hexadecane liquid layer and low‐modulus gel surface, the coating displays outstanding sliding properties to various fluids as well as impressive repellence to bacteria. The water sliding angles on OIGs are below 5° as measured by a water contact angle system. Moreover, it can serve as a barrier against corrosion medium and can be in situ repaired by the laser irradiation based on photothermal effect once damaged. The electrochemical impedance spectroscopy indicated the impedance modulus at 0.01 Hz (|Z|0.01Hz) of the OIG coatings on Q235 substrate is 6.34 × 109 Ω cm2, and the repairing process was monitored by the scanning Kelvin probe microscope. This research proposes a novel strategy to prepare the self‐repairing coatings for anti‐adhesion and anti‐corrosion based on the physically cross‐linked oil‐impregnated gel. [ABSTRACT FROM AUTHOR]

The weak interface adhesion between high‐strength‐high‐modulus polyimide (PI) fibers and epoxy (EP) resin matrix has seriously hampered the application of PI/EP composites. Herein, a waterborne polyamide (WPA) sizing agent was used to modify PI fibers to enhance the interface adhesion strength between the PI fibers and EP resin matrix. The surface characteristics of PI fibers were investigated to determine chemical composition, morphology, roughness, wettability, interfacial shear strength (IFSS) and interlinear shear strength. The results indicated that the WPA sizing agent significantly enhanced the interface adhesion properties between the PI fibers and EP resin matrix with a 132% and 22.35% increment obtained for IFSS and interlaminar shear strength (ILSS) compared with unsized PI/EP composites. Then, the hybrid sizing agent generated by WPA and waterborne EP sizing agent exhibited the highest interface adhesion with 168.65% and 28.62% increment obtained for IFSS and ILSS compared with unsized PI/EP composites. Based on these results, a sizing mechanism with chemical interaction and mechanical interlocking was proposed, which provides an effective and feasible method to enhance the interface adhesion between the PI fibers and EP resin matrix. [ABSTRACT FROM AUTHOR]

Transient current measurements were carried out for polyvinylidene fluoride:polysulfone (PVDF:PSF) blends films of different ratios under different polarizing fields and polarizing temperatures in absorption and desorption mode. The time‐dependent desorption current in polymer blend samples interprets the combined effect of dipole reorientation, space charge dissipation, and hopping of charge carriers. The activation energy has been calculated using the isochronal curve. Thermal activation behaviors of isochronal current in a specific temperature scale followed by a peak centered at about 120–160°C, have indicated the close correlation of transient currents with the dielectric loss peak. The presence of a dielectric loss peak for each polyblend concentration may be due to the existence of relaxing dipoles in the polyblend. With increasing concentration of PSF in the polyblend, this peak tends to shift toward the higher frequency range and suggests the speeding up of the dipolar relaxation process. The dielectric loss factor of polyblend thin films using transient study in absorption and desorption mode using applied step voltage f is related to Hamon's frequency (0.1/t). [ABSTRACT FROM AUTHOR]

The morphology and elemental compositions at the surface of poly(styrene sulfonic acid) (PSSA) grafted poly(ethylene‐co‐tetrafluoroethylene) polymer electrolyte membranes (ETFE‐PEMs) in a grafting degree (GD) range of 0%–127% are investigated by using FE‐SEM and XPS analyses. The concentrations of elemental components at the surface are not a linear function of GDs, resulting from different grafting speeds at the surface and bulk. In addition, low accumulation of PSSA grafts on the surface of ETFE‐PEMs in the low GDs of 0%–19%, as well as their homogeneous distribution through the membranes at least at a GD of 19% are observed. At higher GDs of 19%–127%, the PSSA accumulation on the surface is relatively limited, indicating the presence of more PSSA grafts inside the bulk than on the surface. The surface signatures of ETFE‐PEMs over the entire GD range can be determined based on the grafting process. These interesting observations suggest the significant advantages of interfacial properties of ETFE‐PEMs for fuel cell applications. [ABSTRACT FROM AUTHOR]

This paper focuses on the calculation of the interfacial tension of two systems: low‐density polyethylene with isotactic polypropylene and high‐density polyethylene with syndiotactic polypropylene. For this, three methods to measure the interfacial tension are compared: the use of Palierne's model, and Gramespacher and Meissner's model, both based on additional elasticity or long relaxation times brought by shape recovery of dispersed phase, and ab‐initio calculation, which requires the knowledge of the surface tension of the neat polymer measured at the same temperature. For that, a database collected from the literature is built in the first section of this paper, whether for the studied systems or for other systems of various olefinic homopolymers or copolymers with polypropylene. The results show the effectiveness of the Gramespacher and Meissner's model to calculate the interfacial tension of the studied systems for which the results were in agreement with ab‐initio calculation and Palierne's model. Extension of the ab‐initio calculation to olefinic copolymers was proposed. [ABSTRACT FROM AUTHOR]

The development of new bio‐based epoxy resins and the search for new application areas have become important research directions for bio‐based epoxy resins. Using protocatechuic acid (PA) as a bio‐based raw material, brominated alkenes with different chain length were introduced into PA through substitution reaction, and then oxidized to obtain epoxy resins (PA‐EP) with different epoxy values. After that, it was introduced into epoxy resin (diglycidyl ether bisphenol A [DGEBA]) sizing agent to replace part of DGEBA to prepare new sizing agents. Sizing amount test and sizing CF surface morphology show that the introduction of PA‐EP with high‐epoxy value made it easier be adhered to carbon fiber (CF) surface during sizing process. Interfacial shear strength and interlaminar shear strength of composite made of sizing CF (20 wt% PA‐EP‐3) were 56.86% and 30.29% improvement against the bare CF, which was attributed to the increase in surface energy and epoxy groups after CF sizing. Therefore, PA‐EP with high‐epoxy value was applied as sizing agent for improving interface performance of CF for the first time, and this application was less affected by its low‐output problem compared to its application as a matrix resin in the field of composite manufacturing. [ABSTRACT FROM AUTHOR]

It is well known that poor interlayer adhesion from limited diffusion and entanglement of chains across the interlayer interface is the main reason for anisotropy of mechanical properties of 3D printed parts prepared by fused deposition modeling (FDM). The present study demonstrates the effects of a protective atmosphere and secondary treatment to improve fusion between filaments. The experimental results demonstrate that the mechanical properties of the parts with nitrogen protection increase by about 100% in the direction of filament accumulation while the oxidation degree of the surface of the filament drops by 9%, which indicates that the bond strength between the filaments is improved. And tensile strength is increased by about 10%–20% in the direction of filament accumulation after heat treatment and microwave treatment. [ABSTRACT FROM AUTHOR]

Using plant derived polymers for the composite production has been considering as an efficiently attempt to reduce the impacts from the environmental pollution as well as utilizes the benefits they can bring. Fully jute/polyamide 11 (PA11) biocomposites are green materials expected to own many outstanding advantages of both components for example, high‐mechanical performances and especially environmentally friendliness. However, to the best of our knowledge, these materials has not been studied so far. This work focuses on the further modification of alkaline pre‐treated jute fibers by using vinyltrimethoxysilane (VTMS) and evaluates the effect of silanization on the interaction and adhesion between jute fibers and PA11 resin as well as the characteristics of resulting composites. By using Fourier transform infrared, thermogravimetry, mechanical property analysis, color difference measurement, and scanning electron microscopy observations, the contribution of VTMS modification to the enhancement on the interfacial interaction and adhesion between fibers and PA11 resin proved clearly. The results showed that tensile strength, impact strength; and Young's modulus of silanized jute biocomposites increased by 44.1; 26.5 and 55.6%, respectively in comparison to those of untreated fiber biocomposites. Similarly, thermal stability, resistance to water absorption and weathering resistance of obtained biocomposites were improved. [ABSTRACT FROM AUTHOR]

Characterizing and understanding composite polymeric systems' rheological behavior is essential to tune their melt flow in polymer processing machinery. Also, rheological tests are suitable tools to evaluate the microstructure and interface adhesion of polymeric composites, which are relevant parameters on the composite performance in their applications. Poly(acrylonitrile‐co‐butadiene‐co‐styrene) (ABS) and its composites are essential materials used to manufacture consumer goods necessary to maintain the quality of life of human beings. In this work, we report on polymer systems based on ABS and poly(styrene‐block‐ethylene‐co‐butylene‐block‐styrene)‐graft‐maleic anhydride (SEBS‐g‐MA) as polymer matrix containing dispersed copper microparticles (ABS:SEBS‐g‐MA:Cu). Polydopamine, a bioinspired polymer, was applied as a filler‐matrix interface compatibilizer of the composites. The linear viscoelastic rheological measurements evidence a shear‐thinning behavior for the composites, and the polydopamine coating affects the polymer phase's relaxation time. The cohesive energy density (Ec) and SEM micrographs indicate good adhesion between copper and ABS:SEBS‐g‐MA due to polydopamine interfacial adherence. [ABSTRACT FROM AUTHOR]

Smooth polystyrene (PS) and polyamide 12 (PA 12) surfaces were produced via an injection molding process followed by a smoothing process and subsequently treated with O2 plasma to increase the number of polar groups capable of hydrogen bond formation on the surface. The presence of related groups was evident from X‐ray photoelectron spectroscopy (XPS) and contact angle measurements. The sample topographies were investigated by atomic force microscopy (AFM). The plasma treatment allowed the joining of the substrates without adhesive by pressing the substrates together below or around the glass transition temperature. Notably, not only substrates of the same polymer but also PS and PA 12, which are incompatible, were joined with this method. The adhesion between the substrates was determined using a LUMifrac apparatus. The adhesion strength increased with increasing bonding temperature and when both substrates were plasma‐treated, reaching adhesive strengths up to 5.5 ± 1.7 MPa. Remarkably, the joint substrates could be rapidly de‐bonded on demand simply by treatment with water, and the separated substrates could be re‐bonded by renewed plasma treatment. [ABSTRACT FROM AUTHOR]

The dielectric and physical‐mechanical properties of organophosphorus polyurethane ionomers based on the ethers and aminoethers of ortho‐phosphoric acid have been investigated. The influence of the content of ionogenic groups and polyphosphate structures on the dielectric properties of polyurethanes has been analyzed. It is shown that the values of dielectric permittivity and tangent of dielectric loss in a wide frequency range increase with the content of ionogenic groups in polyurethanes studied. In this case, the increase in conductivity is diffusive in nature and is due to the mobility of protons within the phosphate anion clusters. The compositions of samples with a combination of high dielectric properties and excellent physical‐mechanical and adhesion characteristics have been determined. These are samples in which polyphosphate structures are present in addition to phosphate anions. [ABSTRACT FROM AUTHOR]

Electroplating on acrylonitrile‐butadiene‐styrene (ABS) is a widely used decorative technique for achieving low cost and light weight. However, the lack of adhesion strength can be a threat to the passenger's safety in an emergency situation. Herein the morphology formation of injection molded ABS and the resultant adhesion behavior was investigated from the perspective of rheological analysis. The polybutadiene (PBD) rubbers and styrene‐co‐acrylonitrile (SAN) generated a strong internal structure, which became more strengthened at the low shear level of 0.1 rad/s. As shear rate increased, the deformation of PBD was dominant over the shear level of 10 rad/s. Injection molded specimen and door handle showed extremely oriented ellipsoidal morphology at the gate and squashed structure at the parting line. The etched surface morphology directly influenced the physically interlocked structure, and the deformed surface exhibited negative effect on the adhesion property. 8.11 N/cm of peel‐off strength of electroplated ABS at the injection rate of 10 mm/s decreased to 4.27 N/cm at the injection rate of 50 mm/s. The decrease in peel‐off strength was more noticeable at near gate than center region of the specimen. [ABSTRACT FROM AUTHOR]

Alkali metal anodes paired with solid ion conductors offer promising avenues for enhancing battery energy density and safety. To facilitate rapid ion transport crucial for fast charging and discharging of batteries, it is essential to understand the behavior of point defects in these conductors. In this study, we investigate the heterogeneity of defect distribution in two prototypical solid ion conductors, Li 3 OCl and Li 2 PO 2 N (LiPON), by quantifying the defect formation energy (DFE) as a function of distance from the surface and interface through first-principles simulations. To simulate defects at the electrode-electrolyte interface, we perform calculations of Li + vacancy in Li 3 OCl near its interface with lithium metal. Our results reveal a significant difference between the bulk and surface/interface DFE which could lead to defect aggregation/depletion near the surface/interface. Interestingly, while Li 3 OCl has a lower surface DFE than the bulk in most cases, LiPON follows the opposite trend with a higher surface DFE compared to the bulk. Due to this difference between bulk and surface DFE, the defect density can be up to 14 orders of magnitude higher at surfaces compared to the bulk. Further, we reveal that the DFE transition from surface/interface to bulk is precisely characterized by an exponentially decaying function. By incorporating this exponential trend, we develop a revised model for the average behavior of defects in solid ion conductors that offers a more accurate description of the influence of grain sizes. Surface effects dominate for grain sizes ≲1 μm, highlighting the importance of surface defect engineering and the DFE function for accurately capturing ion transport in devices. We further explore the kinetics of defect redistribution by calculating the migration barriers for defect movement between bulk and surfaces. We find a highly asymmetric energy landscape for the lithium vacancies, exhibiting lower migration barriers for movement toward the surface compared to the bulk, while interstitial defects exhibit comparable kinetics between surface and bulk regions. These insights highlight the importance of considering both thermodynamic and kinetic factors in designing solid ion conductors for improved ion transport at surfaces and interfaces.

Most waterborne epoxy resin emulsifiers are inactive, and the free emulsifier will precipitate out during the curing of the coating film, which will seriously affect the water resistance, solvent resistance, and hardness of the coating film. Herein we prepared a new type of nonionic active epoxy emulsifier. First, 1,4‐butanediol diglycidyl ether reacts with polyethylene glycol at a higher temperature to form an epoxy‐terminated modified hydrophilic segment. Then 2,4‐toluene diisocyanate link the hydrophilic segment and the epoxy resin E‐31 (according the reactivity of the hydroxyl group on the epoxy resin E‐31) to obtain an emulsifier for emulsifying epoxy resins. The synthesized emulsifier's cloud point is 89°C and hydrophilic–lipophilic balance is about 13.1. The most suitable condition of the phase inversion is that the emulsification temperature is 60°C and the stirring speed is 1500 r min−1. The coating films obtained from synthesized emulsifier is dense and uniform with excellent mechanical properties. [ABSTRACT FROM AUTHOR]

Thin‐layer photodegradable polyrotaxane (PRX) gel‐immobilized surfaces were fabricated to investigate the photoregulation of surface properties. Photodegradable PRXs comprising α‐cyclodextrin as a cyclic molecule, poly(ethylene glycol) as a polymer axel, and bulky trithiocarbonate as a photolabile stopper molecule (PRX‐MTP) were utilized for the fabrication of thin‐layer gels. PRX‐MTP gels were prepared on the surface of the glasses, where the surfaces were treated with an isocyanate group‐containing silane coupling agent to allow the covalent immobilization of the PRX‐MTP gels. This PRX‐MTP gel layer was disappeared upon irradiation with ultraviolet (UV; 365 nm) or visible light (465 nm) for 2 h due to the photodegradation of PRX‐MTPs. The surface wettability and roughness were changed owing to the photodegradation of the PRX‐MTP gel layer. When cells were seeded on the PRX‐MTP gel surfaces, adhesion was not observed. However, visible light irradiation of the PRX‐MTP gel layer resulted in cell adhesion on the irradiated surfaces. Consequently, it was determined that the surface properties and cell adhesiveness of the PRX‐MTP gel surfaces could be regulated by visible light irradiation. The photodegradable PRX‐MTP gel surfaces could be utilized for research on cell patterning, cell function control, and advanced cell culture system. [ABSTRACT FROM AUTHOR]

Magnetic Fe3O4/PANI core‐shell composites were prepared as the support of gold catalysts. The Fe3O4 magnetic core was prepared by solvothermal reaction and coated with polyaniline (PANI) shell via in situ aniline polymerization on Fe3O4 surface. Au nanoparticles were loaded on Fe3O4/PANI composites through gold sol adsorption and in situ reduction method to prepare Fe3O4/PANI/Au(Sol) and Fe3O4/PANI/Au(In Situ) catalysts, respectively. We found that the initial activities of Fe3O4/PANI/Au(Sol) were higher than that of Fe3O4/PANI/Au(In Situ) due to the small size effect of Au in catalysts. Although the size of Au in Fe3O4/PANI/Au(In Situ) was bigger than that in Fe3O4/PANI/Au(Sol), it should be noted that both of Fe3O4/PANI/Au(Sol) and Fe3O4/PANI/Au(In Situ) possessed good catalytic recycling stability. The conversion of 4‐NP was still above 97% and 99% after 15 cycles for Fe3O4/PANI/Au(Sol) and Fe3O4/PANI/Au(In Situ), respectively. The good catalytic stability for Fe3O4/PANI/Au(In Situ) could be attributed to the stronger interaction between PANI and Au NPs. We believe that our work provides an effective strategy for the preparation of long‐life catalysts and the investigations can be used to design other conductive polymers supported noble metal catalysts. [ABSTRACT FROM AUTHOR]

Using thermal‐oxidative aging and tribological experiments, effects of thermal‐oxidative aging processes on tribological properties of polyformaldehyde (POM) and ultra‐high molecular weight polyethylene (UHMWPE) were evaluated and compared with each other. It was found that the color of UHMWPE surface after aging has turned to yellow, while that of POM surface has no obvious change. The aging factors lead to dimensional change of UHMWPE disk specimens from the original circle to the ellipse in the meantime. Tribological experiments show that friction coefficients of the pairs of POM/GCr15 and UHMWPE/GCr15 tend to decrease after thermal‐oxidative aging, and the decreasing tendency in friction coefficients of POM/GCr15 is more distinct. The results of this study will contribute to the understanding of the relationship between aging and tribological properties of POM and UHMWPE, and enrich the theory of polymer tribology. [ABSTRACT FROM AUTHOR]

In this paper, polylactic acid porous materials were prepared by a fused deposition modeling 3D printing method. Then, a combination of methyl ethyl ketone (MEK) solution etching containing hydrophobic nano‐silica (HN‐SiO2) and low surface energy fluorosilane modification was used to obtain the samples with different wettability. The effect of immersion time in MEK solution and HN‐SiO2 content on the wettability of porous samples was investigated. Finally, the sample with the highest contact angle and extremely low sliding angle was selected for the oil/water separation test. The separation efficiency of oil/water separators with hole side lengths of 0.8, 1.0, and 1.2 for five different oil/water mixtures was investigated. The results show that the oil/water separator with a hole side length of 1.0 mm has a better primary separation effect. With the increase of the hole size of the oil–water separator, the effect of multiple separations is unfavorable. The oil/water separator with hole side length of 0.8 mm has repeatable oil/water separation performance many times. This research provides a new idea for the application of the oil/water separator with a hole side length greater than 0.6 mm printed by an ordinary, inexpensive, low‐precision fusion 3D printer. [ABSTRACT FROM AUTHOR]

The metal organic frameworks (MOF‐5) with nanoscale porosity and organic–inorganic heterocyclic structure were chemically grafted onto carbon fibers by solvothermal for forming high mechanical interlocking composite architectures and releasing the interfacial forces, so as to obtain carbon fiber reinforced composite with excellent mechanical and tribological properties. With the multi‐scale enhancement of MOF‐5, the optimized tensile and bending strength of the composite increased by about 177.9% and 81.3%, respectively. Moreover, the friction coefficient was higher and relatively stable under the continuous wet friction condition, as well as the wear rate was reduced by 44.4%. The work suggests that the application of MOFs can be extended to the field of structural composites. [ABSTRACT FROM AUTHOR]

The adsorption of particles on cotton affects its performance. Investigating the factors that affect particle adsorption on cotton can provide valuable insights into the adsorption process. By characterizing morphology, composition, structure, surface energy, and specific surface area, this study explores the adsorption of poly (butyl methacrylate) (PBMA) nanocapsules (NCs) on cotton via impregnation, including a preliminary study on the effect of concentration on adsorption. The results yield the following conclusions: (i) the viscosity of the PBMA emulsion increases with concentration, resulting in heightened particle adsorption on cotton and a thicker film after drying; (ii) the acidity and heat resistance of the cotton increase, owing to the formation of hydrogen bonds between the hydroxyl groups in PBMA and cotton and the increased hydrogen bonding interactions with adsorption; (iii) although the adsorption of PBMA NCs on cotton fibers causes a slight decrease in crystallinity and crystal plane spacing, the cotton retains impressive hydrophilicity, wettability, air permeability, and a porous structure. Based on these results, the study proposes a novel approach for the development of functional textiles. [ABSTRACT FROM AUTHOR]

A novel strategy for fabricating waterborne superhydrophobic coatings with controllable adhesive force to water‐droplet has been developed by blending the amphiphilic silica nanoparticles modified using thermally sensitive amphiphilic polymers with polymer latex, which could be applied for self‐cleaning or no loss transfer of microdroplets. And a theoretical analysis of the relationship between the surface chemical composition and the water‐droplet adhesion of the superhydrophobic nanocomposite coating is proposed. [ABSTRACT FROM AUTHOR]

Fish sarcoplasmic proteins (FSP) account for 20%–40% of the muscle protein and its high‐value utilization has become an urgent problem to be solved. Here, directly freeze‐dried sarcoplasmic protein (DFSP) and chitosan flocculated sarcoplasmic protein (CFSP) nanofibers were successfully fabricated by electrospinning technology and characterized in terms of morphology, chemical interaction, surface and mechanical properties, and thermal stability. SDS‐PAGE indicated similar protein bands for both DFSP and CFSP. Scanning electron microscopy observation showed good spinnability for CFSP and DFSP. Fourier transform infrared spectrometry and X‐ray diffraction results unveiled an interaction between sarcoplasmic protein and chitosan in CFSP nannofiber. Furthermore, CFSP nanofiber exhibited better performance than DFSP nanofiber in surface hydrophobicity, thermal stability, elasticity and flexibility. These results suggest the potential application of FSP nanofiber in functional components or drugs delivery, contributing to high‐value utilization of FSP. [ABSTRACT FROM AUTHOR]

The dispersion and distribution of carbon nanotubes (CNTs) on/in the polymer composites are greatly affected by the molding technology progress, which results in different electrical conductivity. The uncontrollable electrical conductivity has limited the application of conductive polymer composites, for example, sensor components. In this work, to enhance the dispersion stability of CNTs in polyethylene (PE) matrix, sub‐micron calcium carbonate isolated CNTs (smCaCO3@CNTs) were selected based on the fact that smCaCO3 is much easier to disperse in polymer in comparison with CNTs. This good distribution of CNTs in smCaCO3@CNTs/PE was characterized by transmission electron microscope and Raman mapping. The electrical performance test results show that when 0.5 wt% of CNTs filled in smCaCO3@CNTs/PE, the percolation network begins to form; when CNTs filled increases to 1‐2 wt%, the surface resistance of smCaCO3@CNTs/PE ranges from 106 to 109Ω almost not affected by the molding technology process (compression molding or injection molding). The possible reason is that the isolated CNTs by smCaCO3 in polymer matrix are favorable for the formation of the stable conductive network. [ABSTRACT FROM AUTHOR]

In a blend of acrylic block copolymer consisting of poly(methyl methacrylate) and poly(n‐butyl acrylate) blocks and a special rosin ester resin (RE) tackifier as a model pressure‐sensitive adhesive (PSA), RE exists in two states: as nm‐sized agglomerated particles (A) and as dissolved molecules (B). The effect of A and B ratio on the PSA properties were investigated using REs with four different weight‐average molecular weights (Mws) in the range from 680 to 1700. The formation of A increased with increasing of Mw because of lowering of miscibility. The glass transition temperature increased with increasing of Mw. The tack at lower temperatures and the fracture energy were improved by B, whereas the tack at higher temperatures was improved by A. A and B enhanced the cohesive strength and the wettability of PSA, respectively. However, the improvement of cohesive strength by the RE with highest Mw was remarkably low. This seems to be caused by the larger size of agglomerated particles. 1H pulse nuclear magnetic resonance analysis was useful for estimating the degree of A formation. The model PSA investigated in this study was nanocomposite‐like. [ABSTRACT FROM AUTHOR]

In the surface treated inorganic particles with silane coupling agent (SCA), chemisorbed and physisorbed molecules are present in the treated layer. Increasing the amount of chemisorption by increasing the molecular weight of SCAs was investigated. Oligomers formed via self‐condensation during storage more than 10 days at room temperature for 3‐methacryloxypropyltrimethoxysilane‐treated silica particles. Monomeric SCA evaporates easily by heating. The oligomers restrict evaporation, and heating increases the chemisorption. The influence of molecular weight of SCA was investigated. In the case of amino group, the amount of chemisorbed was greater for aminoethylaminooctyltrimethoxysilane with high molecular weight than for 3‐aminopropyltriethoxysilane. For SCAs with hydrocarbon chains, the amount of chemisorption was lower for both low molecular weight molecules and decyltrimethoxysilane (D) with a high molecular weight. For fluorocarbon chains, the amount of chemisorption was lower for low molecular weight molecules, whereas it increased significantly by heating for high molecular weight type of 1H,1H,2H,2H‐heptadecafluorodecyltriethoxysilane (F). Wide‐angle X‐ray diffraction analysis of F‐treated silica particles showed that the fluorocarbon chains formed an ordered structure. There was no such indication for the D‐treated system. This ordered structure seems to influence on higher chemisorption for F‐treated systems. [ABSTRACT FROM AUTHOR]

Here, we introduce a highly porous functional mesoscopically silica‐polymer composite based on silica monolith‐conjugated thiourea/formaldehyde copolymer. The developed nanostructure enables selective and fast removal of the radioactive pollutants strontium (Sr[II]) and cesium (Cs[I]) ions from contaminated seawater. The silica/polymer composite was synthesized by introducing thiourea/formaldehyde solution into tetramethoxy orthosilicate/triblock copolymer emulsion. The chemical and textural features of the synthesized silica/thiourea‐formaldehyde polymer composite (SiO2‐TUF) were characterized using Fourier transform infrared spectroscopy, X‐ray photoelectron spectroscopy, scanning electron microscope, high‐resolution transmission electron microscope, energy dispersive X‐ray analysis, dynamic light scattering, thermal analysis, and N2 adsorption/desorption measurements. The synthesized microporous SiO2‐TUF showed excellent cesium and strontium ions removal ability, reaching a maximum adsorption capacity of 78.2 and 40.3 mg g−1 for Sr(II) and Cs(I), respectively. When tested with seawater contaminated with radioactive cesium and strontium, SiO2‐TUF was able to selectively target Sr(II) and Cs(I) ions. Among the different types of adsorption isotherms investigated, Sips isotherm showed the best fit with R2 > 0.990. The kinetic studies showed that the pseudo‐second‐order model gave the best description of the uptake process. [ABSTRACT FROM AUTHOR]

Elastomeric heat shielding materials (EHSMs) are necessary to protect combustion chambers of solid rocket motors during their working. Poly(diaryloxyphosphazene) (PDPP) elastomers own inherent thermal stability and flame retardancy because the backbone of alternating phosphorus and nitrogen atoms can be a novel promising polymer matrix toward EHSMs. The present study deals with the development of a novel PDPP based EHSMs with several different fibrous reinforcements, including Kevlar, polyimide, and carbon short fibers. It is found that PDPP/Kevlar composites show outstanding tensile strength and ablation resistance because of their strong interfacial bonding between matrix and fibers which benefits from the possible network of intermolecular hydrogen bonds. PDPP/carbon composites produce a compact charred layer due to their high char yields of carbon fibers. These results improve the understanding of the role of polyphosphazenes with different kinds of fibers on ablation mechanisms, which enable the possibility to exploit intrinsic properties of polyphosphazenes. [ABSTRACT FROM AUTHOR]

High loadings of fillers are usually needed to achieve high‐thermal conductivity (TC) of polymer‐based composites, which inevitably sacrifices processability and meanwhile causes high‐cost. Therefore, it is of great significance to achieve high‐TC composites under low‐filler loading. Here, a novel p‐phenylenediamine (PPD) modified expanded graphite (EG‐PPD)/epoxy (EP) composite with high TC and low‐filler content was successfully prepared via pre‐dispersion and vacuum assisted mixing strategy. With the improved interfacial compatibility between EG and EP by PPD, the prepared EG‐PPD/EP composite exhibited excellent thermal management performance, resulting in the TC of which reached 4.00 W·m−1·K−1 with only 10 wt% (5.59 vol%) of EG‐PPD, which is approximately 19 times higher than that of pure EP. Meantime, the interface thermal resistance of EG‐PPD/EP composite between EG‐PPD and EP is reduced by 33% compared with EG/EP composite. This composite with excellent TC property is expected to be used in thermal management field. [ABSTRACT FROM AUTHOR]

Currently, microcapsules are attracting great attention and becoming more and more widely used in sustained release system. In this research, zein‐based microcapsules were prepared by anti‐solvent precipitation technology and spray drying. The properties of as‐prepared microcapsules were optimized by adjusting the reaction conditions and parameters such as the mass ratio of zein to vanillin, the drying temperature and whether polyethylene glycol was added or not. Meanwhile, the morphologies, chemical structures, and application performances of microcapsules were characterized and determined by SEM, FT‐IR, TG, and so on. The results showed that the morphology of as‐obtained microcapsules was a regular spherical shape with no cracks when the mass ratio of zein to vanillin was 1:1, the inlet temperature was 120 C and the polyethylene glycol was introduced. Meanwhile, it was also proved that the polyethylene glycol has a positive effect on the encapsulation efficiency in microcapsules. Moreover, zein microcapsules can effectively improve the thermal stability and release behavior of vanillin, meanwhile the exist of polyethylene glycol can further improve the properties of zein microcapsules. This research provided guidelines for the study of microcapsules. [ABSTRACT FROM AUTHOR]

As the development of oilfield exploitation, more and more oil in water (O/W) emulsion was produced, thus efficient reverse demulsifier becomes increasingly important. In this paper, a series of novel reverse demulsifiers (R‐PED1 ~ 4) with the characteristics of polyacrylate and polycation were prepared. The structure of the product was verified by IR specter and 1H NMR. The thermal stability was studied with TGA and the molecular weight was obtained by GPC. Field evaluation results showed that the oil content in produced liquid after R‐PED4 treatment can be reduced from 1550 to 81 mg/L at R‐PED4 dosage was 50 mg/L. Furthermore, the demulsification mechanism of R‐PED was discussed. The R‐PED has good surface/interfacial activity. It can effectively reduce the oil–water interfacial film strength and reduce the zeta potential of oil droplets, which is beneficial for the coalescence of oil droplets. Especially, the interaction force between oil droplets was measured by the optical tweezers. R‐PED4 can increase the attraction force between oil droplets. Consequently, the contact time of oil droplets during the demulsification process can be prolonged and the coalescence of oil droplets also can be effectively promoted. The novel reverse demulsifier offers a new option for the oilfield produced liquid treatment. [ABSTRACT FROM AUTHOR]

Bonding between polymers through interdiffusion of macromolecules is a well‐known mechanism of polymer adhesion. A new polymer bonding mechanism in the solid state, taking place at ambient temperatures well below the glass transition value (Tg), has been recently reported; in this mechanism, bulk plastic compression of polymer films held in contact led to adhesion over timescales of the order of a fraction of a second. In this study, we prepared various blends of plasticized polymer films with desirable ductility from amorphous and semicrystalline powders of hydroxypropyl methylcellulose and polyvinyl alcohol derivatives; then, we observed the bonding of these polymers at ambient temperatures, up to 80 K below Tg, purely through mechanical deformation. The deformation‐induced bonding of the polymer films studied in this work led to interfacial fracture toughnesses in the range of 1.0–21.0 J/m2 when bulk plastic strains between 3% and 30% were imposed across the films. Scanning electron microscopy observation of the debonded interfaces also confirmed that bonding was caused by deformation‐induced macromolecular mobilization and interpenetration. These results expand the range of applicability of sub‐Tg, solid‐state, deformation‐induced bonding processes. [ABSTRACT FROM AUTHOR]

Fiber‐metal laminates (FMLs) offer the superior characteristics of polymer composites (i.e., light weight, high strength and stiffness) with the ductility and fracture strength of metals. The bond strength between the two dissimilar materials, composite and metal, dictates the properties and performance of the FMLs. The bonding becomes more critical when the polymer matrix is thermoplastic and hydrophobic in nature. This work employed a novel bonding technique between thermoplastic composites and a metal layer using six different combinations of organic coatings. The flexural, and interlaminar shear strength of the thermoplastic fiber metal laminates (TP‐FMLs) were examined to investigate the bond strengths in the different cases along with fracture characteristics revealed from the tested samples using scanning electron microscopy. The viscoelastic performance of the fabricated TP‐FMLs were also investigated using the dynamic mechanical thermal analysis method. [ABSTRACT FROM AUTHOR]

The influence of selective localization of the nanoclay Cloisite 30B on the morphological, thermal and thermo‐mechanical properties of biodegradable poly(lactic acid)/poly(hydroxybutyrate) blends was evaluated in this work. For this, different compounds were obtained by adding the filler in a single phase or mixed with the two matrices simultaneously by melting processing. The simultaneous processing leads to a better dispersion of nanoparticles on the blend and generates a more homogeneous polymer interface, but the properties do not increase in relation to those that were processed in separate steps. For the blends obtained in separated steps, the polymeric domains and, consequently, the superficial tension between phases are better controlled by a nanolayer. Thus, the results obtained in this work indicate that better control of the polymeric interfaces can generate a more significant effect on the thermal and thermo‐mechanical properties of nanostructured blends than just a good dispersion of the fillers. [ABSTRACT FROM AUTHOR]

In order to improve the interfacial adhesion between aramid fiber (AF) and rubber matrix, a simple and facile method of aramid nanofiber (ANF) coating is demonstrated in this article. Tannic acid (TA) and polyethyleneimine (PEI) are polymerized in an alkaline solution to form a thin TA/PEI (TP) layer that is deposited on the surface of AF to introduce functional groups such as hydroxyl and amino groups. Then, the ANF coating is utilized to construct nanostructures on the surface of AF to improve the interfacial adhesion between the fiber and the rubber. Through hydrogen bonding and/or π‐π stacking between the TP layer and the ANF, the ANF coating is firmly attached to the surface of AF. Compared with the untreated fiber, the interfacial adhesion of AF coated with ANF after 1, 3, 5, 7, 9 deposition cycles is increased by 27.8%, 29.1%, 31.5%, 43.1%, and 30.3%, and the mechanical properties of the fibers remain almost unchanged. This method shows its advantages of simple, facile, and time‐effective, which is of great significance for industrial applications. [ABSTRACT FROM AUTHOR]

The application of polyolefins has increased significantly over the past few decades. However, their chemical inertness and low surface energy limits their application in many industries where high adhesion to polar materials is required, such as for composites and protective coatings. Herein, six different acids are used to create polar functional groups on High‐Density Polyethylene's (HDPE) surface and to increase its adhesion to liquid epoxy (LE). Contact angle measurements, Fourier Transform Infrared Spectroscopy (FTIR), X‐ray Photoelectron Spectroscopy (XPS), and pull‐off strength measurements are used to analyze the surface energy and functionality of HDPE and to measure its adhesion to LE. The results show that each acid increases both the polar and disperse surface energies of HDPE to a different extent, but that this is not necessarily a function of acid strength. Chlorosulfonic acid and chromic acid increase the oxygen to carbon ratio by a factor of 8 and increase HDPE's adhesion to LE by more than 400%. Furthermore, a comparison between predicted work of adhesion values from the OWRK model and experimental results shows that the latter are significantly higher than what is predicted, especially with increasing surface polarity. [ABSTRACT FROM AUTHOR]

Poly(N‐vinylcarbazole), two dihalogenated derivatives, and nanocellulose/poly(N‐vinylcarbazole) nanocomposite thin films have been fabricated with micrometric pore topography. This patterned structure has been developed by using breath figure method, which is an easy and cost‐effective method to obtain honeycomb‐like arrays. In addition, the effect of the dihalogenated substitutions and the presence of nanocellulose fillers in the topography and conformational entropy were evaluated. The conformational entropy of each sample was calculated by using Voronoi tessellation. It is important to notice that highly regular patterns have been obtained from this photoconductive polymer, since the conductivity of this kind of material is proportional to the absorbed light, this honeycomb‐like topography could improve the light capture and the efficiency of photoelectric conversion, increasing the potential applicability of these materials. [ABSTRACT FROM AUTHOR]

Polypyrrole grains are synthesized by aqueous chemical oxidative polymerization using ferric chloride as an oxidant in the presence of bis(2‐ethylhexyl) sulfosuccinate sodium salt as both a dopant and a hydrophobizing agent. The resulting grain products are characterized in terms of their size, morphology, surface and bulk chemical compositions, hydrophilicity‐hydrophobicity balance, (photo) thermal property, and electrical conductivity. Scanning electron microscopy studies indicate that the grains are aggregates of atypical primary grains with submicrometer size. Elemental microanalysis and thermogravimetric analysis confirm that the polypyrrole is preferably doped with dioctyl sulfosuccinate compared with chloride ion, and dioctyl sulfosuccinate/chloride ion dopant ratio increases with an increase of bis(2‐ethylhexyl) sulfosuccinate sodium salt concentration in the polymerization systems. The grains show near‐infrared light‐to‐heat photothermal property, which is confirmed by thermography. The data obtained through X‐ray photoelectron spectroscopy indicate the presence of dioctyl sulfosuccinate dopants on the surface of the grains, and therefore the dried polypyrrole grains show hydrophobic character. The dried grains can work as a light‐responsive liquid marble (LM) stabilizer. Motions of the LM can be driven by near‐infrared laser irradiation‐induced Marangoni flow on planar air‐water surface. The release of internal liquid can be achieved by controlled disruption of the LM via external stimulus application. [ABSTRACT FROM AUTHOR]

In this work, Bis‐(3‐triethoxysilylpropyl) tetrasulphane was employed for surface modification of silica, ferrite and kenaf fiber filled natural rubber composites using aqueous solvent deposition, dry blending and integral blend methods. The efficiency of each method and the preferred modification method for improving the mechanical performance of natural rubber composites was assessed. The appearance of the Fourier transform infrared spectroscopy peak around 1088 cm−1 for all types of fillers provided evidence that silane interaction had occurred between the fillers and rubber and the formation of siloxane linkages were quantitatively determined by the crosslink density measurement. The surface treatment by dry method for silica and ferrite fillers showed significant improvement of tensile performance at approximately 67% and 34% compared to those with untreated fillers. For kenaf fiber‐filled rubber composites, the surface treatment by aqueous solvent deposition showed the highest tensile improvement of 59% compared to the dry blending and integral blend method. [ABSTRACT FROM AUTHOR]