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The diffusion kinetics of a molecular probe—rhodamine B—in ternary aqueous solutions containing poly(vinyl alcohol), glycerol, and surfactants was investigated using fluorescence correlation spectroscopy and dynamic light scattering. We show that the diffusion characteristics of rhodamine B in such complex systems is determined by a synergistic effect of molecular crowding and intermolecular interactions between chemical species. The presence of glycerol has no noticeable impact on rhodamine B diffusion at low concentration, but significantly slows down the diffusion of rhodamine B above 3.9% (w/v) due to a dominating steric inhibition effect. Furthermore, introducing surfactants (cationic/nonionic/anionic) to the system results in a decreased diffusion coefficient of the molecular probe. In solutions containing nonionic surfactant, this can be explained by an increased crowding effect. For ternary poly(vinyl alcohol) solutions containing cationic or anionic surfactant, surfactant—polymer and surfactant—rhodamine B interactions alongside the crowding effect of the molecules slow down the overall diffusivity of rhodamine B. The results advance our insight of molecular migration in a broad range of industrial complex formulations that incorporate multiple compounds, and highlight the importance of selecting the appropriate additives and surfactants in formulated products.

Waterborne silicone coatings are prepared in this paper by using silicone emulsion as a film-forming material, γ-methacryloxypropyltrimethoxysilane, and dibutyltin dilaurate as a curing agent and a catalyst, respectively. The corresponding coatings are obtained by controlling different microwave times to accelerate the coating curing. The surface morphology, roughness, surface properties, mechanical properties, and antifouling properties of the coating are studied by laser confocal microscope, contact angle measurement, tensile test, marine bacterial attachment test, and benthic diatom adhesion test. Additionally, the action mechanism of microwaves in the curing process of the coatings is also discussed. The results show that the microwave can greatly reduce the curing time of waterborne silicone coating. It can improve the painting efficiency, the surface roughness of the coating, and the mechanical properties of the coatings. The change in roughness increases the contact angle of the coating, reduces the apparent surface energy, and then improves the antifouling performance. For the coating cured by microwave, with the increase in microwave curing time, the water and diiodomethane contact angles of the coating gradually increase, and the surface energy gradually decreases from about 20 mJ/m2 to 10.8 mJ/m2. With the increase in microwave time, the attachment amount of Navicular Tenera gradually decreases, the removal rate gradually increases, and the removal rate of Navicular Tenera in the coating increases from 15.36% to 31.78%. The bacterial removal rate of the coating can be increases from 11.05% to 22.28% after microwave curing. Microwave-assisted curing is helpful in improving the antifouling and self-cleaning performance of waterborne silicone coatings, showing promising potential applications.

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To understand the microstructure evolution of hydrogels swollen in seawater, freeze-drying technology was used to fix and preserve the swollen three-dimensional microstructure. By this method, we revealed the swelling behavior of hydrogels in seawater, and elucidated the mechanism of the swelling process. Meanwhile, we also used Fourier-transform infrared spectroscopy; laser confocal microscopy; field emission scanning electron microscopy, and swelling performance tests to research the structure and properties of PS-PEG hydrogels, before and after seawater swelling, and analyzed the structure and properties of PEG-based hydrogels with different contents of polystyrene microspheres. Results showed that PS-PEG hydrogels went through three stages during the swelling process, namely ‘wetting-rapid swelling-swelling equilibrium’. Due to the capillary effect and hydration effect, the surface area would initially grow tiny pores, and enter the interior in a free penetration manner. Finally, it formed a stable structure, and this process varied with different content of polystyrene microspheres. In addition, with the increase of polystyrene microsphere content, the roughness of the hydrogel before swelling would increase, but decrease after swelling. Appropriate acquisition of polystyrene microspheres could enhance the three-dimensional network structure of PEG-based hydrogels, with a lower swelling degree than hydrogels without polystyrene microspheres.

To explore the influence mechanisms of polyurethane soft segments on modified silicone coatings, a series of modified coatings was prepared by introducing different contents of hydroxypropyl-terminated polydimethylsiloxane (PDMS2200) into the soft segment of polyurethane. ATR-FTIR, NMR, CLSM, AFM, contact angle measurement, the tensile test, bacterial adhesion, and the benthic diatom adhesion test were used to investigate the structure, morphology, roughness, degree of microphase separation, surface energy, tensile properties, and antifouling properties of the modified coatings. The results show that PDMS2200 could aggravate the microphase separation of the modified coatings, increase the surface-free energy, and reduce its elastic modulus; when the microphase separation exceeded a certain degree, increasing PDMS2200 would decrease the tensile properties. The PED-TDI polyurethane-modified silicone coating prepared with the formula of PU-Si17 had the best tensile properties and antifouling properties among all modified coatings.

To research the influence of different silicone oil on the properties of the coatings based on polydimethylsiloxane (PDMS) reinforced by hydroxylated multi-walled carbon nanotubes, phenylmethyl silicone oil (PSO), methyl silicone oil (MSO), and the blend of PSO and MSO were incorporated into the antifouling coatings. The surface properties and leaching of silicone oil were investigated by water and diiodomethane contact angle and confocal laser scanning microscopy (CLSM). The mechanical properties were investigated by tensile test, and the antifouling properties were tested via bacterial biofilms and the diatom Navicula tenera adhesion. Results revealed that leaching rate, hydrophobicity, and surface free energy with coating with the blend of MSO and PSO (P/M-PDMS) was between those of the coating with PSO (PSO-PDMS) and coating with MSO (MSO-PDMS). P/M-PDMS was better than MSO-PDMS in resisting fouling organisms. P/M-PDMS prolonged the leaching process of the blend of MSO and PSO and showed better antifouling performance.

The emergence of multi-access edge computing (MEC) aims at extending cloud computing capabilities to the edge of the radio access network. As the large-scale IoT services are rapidly growing, a single edge infrastructure provider (EIP) may not be sufficient to handle the data traffic generated by these services. The coalition method has been used in MEC for resource optimization, latency, energy consumption reduction, computation offloading, etc. However, the majority of research does not consider the price of computing resources corresponded to a container. Moreover, each SP does not choose EIP with the highest cost-performance to sign a medium/long-term computing resource purchase or lease contract. In this work, we consider a scenario with a collection of SPs with different budgets and several EIPs distributed in geographical locations. During the first phase, we get the market equilibrium price and select the optimal EIPs to make a deal by solving the Eisenberg-Gale convex program. In the second stage, using a mathematical model, we maximize EIP's profits and form stable coalitions between EIPs by a distributed coalition formation algorithm. Numerical results demonstrate that the effectiveness of our method is significantly better than the existing model.

Fouling-release coatings reinforced with micro-alumina and nano-alumina were prepared based on polydimethylsiloxane (PDMS) containing phenylmethylsilicone oil. The surface properties, mechanical properties, leaching behavior of silicone oil, anti-fouling and drag-reduction performance of the coating were studied. The results show that the addition of alumina can significantly improve the tensile strength, elastic modulus and Shore’s hardness of the coating. The adhesion experiments of marine bacteria and Navicula Tenera show that the addition of alumina can reduce the antifouling performance of the coating, which is related to the stripping mode of fouling organisms. The fouling organisms leave the coating surface by shearing, and the energy required for shearing is proportional to the elastic modulus of the coating. At 800–1400 rpm, the addition of alumina will reduce the drag reduction performance of the coating, which is related to the drag reduction mechanism of PDMS. PDMS counteracts part of the resistance by surface deformation. The larger the elastic modulus is, the more difficult the surface deformation is. The experiment of silicone oil leaching shows that the increase of alumina addition amount and the decrease of particle size will inhibit the leaching of silicone oil.

The matching application of silicone antifouling coating and epoxy primer is a major problem in engineering. Novel epoxy-modified silicone tie-coating was prepared to tie epoxy primer and silicone antifouling coating. Firstly, N-(2-Aminoethyl)-3-aminopropyltrimethoxysilane was mechanically mixed with bisphenol A epoxy resin to form silylated epoxy resin, then the silylated epoxy resin was uniformly mixed with hydroxy-terminated polydimethylsiloxane and a curing agent and catalyst for coating. An infrared spectrometer, differential scanning calorimeter and tensile tests were used to investigate the chemical structure, phase transition temperature and mechanical properties of the tie-coatings. The interlaminar adhesion of the matching coating system was tested and analyzed by a peel-off test and a shear test. Fracture morphology was observed by scanning using an electron microscope. The results showed that crosslinking density of the tie-coating, the elastic modulus and the tensile strength of the coating increased with an increasing epoxy content, but fracture elongation decreased. The shear strength of the matching coating system is 0.37 MPa, and it shows a good tie performance. The maximum anti-peeling rate of the tie-coating on the epoxy primer reaches 100%.

To improve the mechanical strength and practicability of hydrogels, polystyrene microspheres with core–shell structure were prepared by the soap-free emulsion polymerization, polyethylene glycol hydrogels with polystyrene microspheres by the in-situ polymerization. The structure, morphology, roughness, swelling property, surface energy, and mechanical properties of the microspheres and hydrogels were investigated by Fourier transform infrared spectroscopy, scanning electron microscopy, transmission electron microscopy, confocal laser microscopy, swelling test, contact angle measurement, and compression test. The results showed that they have certain swelling capacity and excellent mechanical properties, and can change from hydrophobic to hydrophilic surface. The reason is that the hydrophilic chain segment can migrate, enrich, and form a hydration layer on the surface after soaking for a certain time. Introducing proper content of polystyrene microspheres into the hydrogel, the compressive strength and swelling degree improved obviously. Increasing the content of polystyrene microspheres, the surface energy of the hydrogels decreased gradually.

The adhesion force between individual human hair fibers in a crosshair geometry was measured by observing their natural bending and adhesive jumps out of contact, using optical video microscopy. The hair fibers' natural elastic responses, calibrated by measuring their natural resonant frequencies, were used to measure the forces. Using a custom-designed, automated apparatus to measure thousands of individual hair-hair contacts along millimeter length scales of hair, it was found that a broad, yet characteristic, spatially variant distribution in adhesion force is measured on the 1 to 1000 nN scale for both clean and conditioner-treated hair fibers. Comparison between the measured adhesion forces and adhesion forces modeled from the hairs' surface topography (measured using confocal laser profilometry) shows they have a good order-of-magnitude agreement and have similar breadth and shape. The agreement between the measurements and the model suggests, perhaps unsurprisingly, that hair-hair adhesion is governed, to a first approximation, by the unique surface structure of the hairs' cuticles and, therefore, the large distribution in local mean curvature at the various individual contact points along the hairs' lengths. We posit that haircare products could best control the surface properties (or at least the adhesive properties) between hairs by directly modifying the hair surface microstructure.

In order to control the leaching of phenylmethylsilicone oil (PSO) reasonably from the fouling release coating based on polydimethylsiloxane, the MWCNTs-OH/Fe2O3 composite coatings was investigated, including the surface properties, the mechanical properties, especially the leaching performance of PSO and the antifouling performance of the coatings. When the content of MWCNTs-OH/Fe2O3 is controlled at 1% of the pigment volume concentration, with the increase of the volume ratio of MWCNTs-OH, the mechanical properties and the surface roughness of the coating increase. The increase in the volume ratio of MWCNTs-OH causes the transformation of the leaching behavior of PSO from the molecular network diffusion to the channel diffusion, enhancing the leaching efficiency of PSO. Moreover, the improvement of the anti-biofilm adhesion performance is confirmed by increase the leaching efficiency of PSO. The panel tests of the antifouling coatings in Yellow sea in China also indicates that coatings had the excellent antifouling effect when the volume ratio of MWCNTs-OH is more than 50% in the mixed powders.

The compatibility of three types of silicone oil with polydimethylsiloxane, the phase separation of their mixture and the microstructure and properties of their composite coatings were investigated. The existing form of silicone oil in the coating and the precipitation behavior were also studied. The compatibility observed experimentally of the three silicone oils with PDMS is consistent with the results of the thermodynamic calculation. The silicone oil droplet produced by phase separation in the mixture solution can keep its shape in the cured coating, also affecting the microstructure and mechanical properties of the coating. It was found that methyl silicone oil and methyl fluoro silicone oil do not precipitate on the surface, and they have no effect on the surface properties of the coating. In contrast, phenyl silicone oil has obvious effect on the surface, which makes the water contact angle and diiodomethane contact angle of the coating decrease significantly.

Polyurethane has a microphase separation structure, while polyethylene glycol (PEG) can form a hydrated layer to resist protein adsorption. In this paper, PEG was introduced to polyurethane to improve the antifouling properties of the polyurethane, providing a new method and idea for the preparation of new antifouling polyurethane materials. The mechanical properties, hydrophilicity, swelling degree, microphase separation and antifouling performance of the coatings were evaluated. The response characteristics of the polyurethane coatings in a seawater environment were studied, and the performance changes of coatings in seawater were tested. The results showed that the crystallized PEG soft segments increased, promoting microphase separation. The stress at 100% and the elasticity modulus of the polyurethane material also markedly increased, in addition to increases in the swelling degree in seawater, the water contact angle decreased. A total of 25% of PEG incorporated into a soft segment can markedly improve the antibacterial properties of the coatings, but adding more PEG has little significant effect. After immersion in seawater, the coatings became softer and more elastic. This is because water molecules formed hydrogen bonding with the amino NH, which resulted in a weakening effect being exerted on the carbonyl C=O hydrogen bonding and ether oxygen group crystallization.

To study the effect of cast defects on the corrosion behavior and mechanism of the UNS C95810 alloy in seawater, an investigation was conducted by weight loss determination, scanning electron microscopy (SEM), confocal laser scanning microscopy (CLSM), X-ray diffraction (XRD) and electrochemical testing of the specimen with and without cast defects on the surface. The results show that the corrosion rate of the alloy with cast defects is higher than that of the alloy without cast defects, but the defects do not change the composition of the resulting corrosion products. The defects increase the complexity of the alloy microstructure and the tendency toward galvanic corrosion, which reduce the corrosion potential from &minus, 3.83 to &minus, 86.31 mV and increase the corrosion current density from 0.228 to 0.23 mA&times, cm&minus, 2.

In order to develop waterborne silicate anticorrosive coatings to replace solvent-based anticorrosive coatings used widely in the shipping industry, epoxy modified silicate emulsions were synthesized with different contents of epoxy resin, then aqueous silicate zinc-rich coatings were prepared with the synthesized silicate emulsion, triethylamine, and zinc powder. The influence of the content of epoxy on the properties and chemical structure of the modified emulsion, mechanical properties of the silicate coatings, and corrosion behavior of the silicate zinc-rich coatings in 3.5% NaCl solution were investigated. The coating samples on steel were measured by the immersion test, Tafel polarization test, and electrochemical impedance spectroscopy (EIS) test with different immersion times. The results showed that epoxy modified silicate emulsions were successfully synthesized. With the increase in epoxy content, the viscosity and solid content of the modified emulsion increased, the impact resistance of the silicate coating rose, the pencil hardness decreased, but the adhesion was not affected. Epoxy modification can reduce, to a certain extent, the corrosion driving force of the zinc rich coating and increase the impedance of the zinc-rich coating, which decreases with the increase of immersion time in 3.5% NaCl solution. With the increase in the epoxy content, the impedance value of the zinc-rich coating increases, indicating that the ability of the coating to resist corrosive media is enhanced.

In order to study whether silica will become a weak point of cavitation of silicone coating and which of the surface roughness, elongation, elastic modulus and hardness has a greater impact on cavitation, composite coatings composed of silicate, polyurethane and silicone coating with different surface roughness, elongation, elastic modulus and hardness containing silica were prepared. The morphology, composition and performance of the composite coatings before and after cavitation were characterized by confocal laser scanning microscope (CLSM), scanning electron microscope (SEM), energy dispersive spectroscopy (EDS), X-ray diffraction (XRD) and weight loss. The results showed that cavitation damage mainly occurs in the silicone polymer matrix rather than the silica reinforced powder. Enlarging the elongation, elastic modulus and hardness of polyurethane coating can improve the cavitation resistance of the composite coatings. The cavitation resistance of composite coatings is closely related to their surface roughness.

In order to figure out the influence of nano-zinc oxide (NZO) on the properties of the fouling release (FR) coating based on polydimethylsiloxane (PDMS) with the incorporation of phenylmethylsilicone oil (PSO), NZO reinforced PSO-PDMS blend coatings were prepared by adjustments to the particle size and pigment-binder ratio (P/B). The surface properties, the mechanical properties, the PSO leaching behavior and the biofilm adhesion assay of the reinforced coatings were investigated. Results indicated that with the increase of particle size and P/B value, surface roughness of the reinforced coatings increased and the mechanical properties of the reinforced coatings were enhanced. The addition of NZO caused PSO to migrate first inside the reinforced coating to form the oil storage sac, then migrate to the reinforced coating surface. Finally, PSO was leached on the reinforced coating surface. Meanwhile, the addition of NZO increased the crosslink density of the reinforced coatings, which caused the decrease of the leaching efficiency of PSO. When the P/B value was more than P/B M , PSO still could not be observed on the reinforced coating surface after 1 year of exposure. And the anti-biofilm adhesion performance of the reinforced coatings decreased due to the increase in difficulty of leaching PSO.

The effect of widely different corrosion rates of Mg alloys on four parameters of interest for in vivo characterization was evaluated: (1) the effectiveness of transdermal H 2 measurements with an electrochemical sensor for noninvasively monitoring biodegradation compared to the standard techniques of in vivo X-ray imaging and weight loss measurement of explanted samples, (2) the chemical compositions of the corrosion layers of the explanted samples by XPS, (3) the effect on animal organs by histology, and (4) the accumulation of corrosion by-products in multiple organs by ICP-MS. The in vivo biodegradation of three magnesium alloys chosen for their widely varying corrosion rates – ZJ41 (fast), WKX41 (intermediate) and AZ31 (slow) – were evaluated in a subcutaneous implant mouse model. Measuring H 2 with an electrochemical H 2 sensor is a simple and effective method to monitor the biodegradation process in vivo by sensing H 2 transdermally above magnesium alloys implanted subcutaneously in mice. The correlation of H 2 levels and biodegradation rate measured by weight loss shows that this non-invasive method is fast, reliable and accurate. Analysis of the insoluble biodegradation products on the explanted alloys by XPS showed all of them to consist primarily of Mg(OH) 2 , MgO, MgCO 3 and Mg 3 (PO 4 ) 2 with ZJ41 also having ZnO. The accumulation of magnesium and zinc were measured in 9 different organs by ICP-MS. Histological and ICP-MS studies reveal that there is no significant accumulation of magnesium in these organs for all three alloys; however, zinc accumulation in intestine, kidney and lung for the faster biodegrading alloy ZJ41 was observed. Although zinc accumulates in these three organs, no toxicity response was observed in the histological study. ICP-MS also shows higher levels of magnesium and zinc in the skull than in the other organs. Statement of significance Biodegradable devices based on magnesium and its alloys are promising because they gradually dissolve and thereby avoid the need for subsequent removal by surgery if complications arise. In vivo biodegradation rate is one of the crucial parameters for the development of these alloys. Promising alloys are first evaluated in vivo by being implanted subcutaneously in mice for 1 month. Here, we evaluated several magnesium alloys with widely varying corrosion rates in vivo using multiple characterization techniques. Since the alloys biodegrade by reacting with water forming H 2 gas, we used a recently demonstrated, simple, fast and noninvasive method to monitor the biodegradation process by just pressing the tip of a H 2 sensor against the skin above the implant. The analysis of 9 organs (intestine, kidney, spleen, lung, heart, liver, skin, brain and skull) for accumulation of Mg and Zn revealed no significant accumulation of magnesium in these organs. Zinc accumulation in intestine, kidney and lung was observed for the faster corroding implant ZJ41. The surfaces of explanted alloys were analyzed to determine the composition of the insoluble biodegradation products. The results suggest that these tested alloys are potential candidates for biodegradable implant applications.

Magnesium (Mg) and its alloys have increasingly been considered as implant materials for orthopedic, craniofacial, and cardiovascular applications. These materials generally have mechanical properties close to those of human bone and they biodegrade in aqueous environments. The biodegradation properties can be tailored to fit the desired application by changing the alloying elements and/or by addition of surface coatings. To test and compare the biodegradation properties of different materials, immersion tests in solutions ranging from simple salt solutions to complex biological media are commonly done that yield some information about the biodegradation rate and the biodegradation products on the surface after completion of the test. Here we report on a method that allows the continuous real-time monitoring of the biodegradation process using electrochemical sensors for pH and H2 during immersion of Mg samples in the cell culture medium DMEM/F12 with different concentrations of fetal bovine serum and in the presence of living cells. The sensors effectively indicated the biodegradation behavior of Mg samples in real-time. This system could be very useful for immersion tests and even supporting biocompatibility testing of implant materials.

Polyurethane have good anti-protein adsorption properties, could be used as an antifouling material. In this study, a type of polyurethane antifouling coating was prepared using 2,4-toluene diisocyanate and 1,4-butanediol as the hard segment and polyether polyols as the soft segment. The influence of hard segment content on the chemical structure, mechanical properties, and surface properties of the coatings was investigated. Subsequently, the antifouling performance of the polyurethane coatings was investigated by benthic diatom adhesion and panel tests. The results showed that coating H40 (polyurethane coating with a hard segment content of 40 wt.%) exhibited the best antifouling property. The antifouling performance of the coatings was further examined by evaluating the surface changes occurring in the polyurethane coatings during immersion in seawater. In situ diiodomethane contact angle measurements were performed to monitor such changes. The oil contact angle results were consistent with the results of the panel test. The oil contact angle and antifouling property are both determined by the surface roughness, which is determined by the level of microphase separation in the polyurethane coatings.

In this study, we explore the effect of phenylmethylsilicone oil (PSO) addition amount and viscosity in a fouling release coating based on polydimethylsiloxane (PDMS). The surface properties, mechanical properties, anti-fouling and drag-reduction performance of the coating were studied. Meanwhile the influence of the basic properties of the coating on the anti-fouling and drag-reduction performance was also studied. Subsequently, the antifouling performance of the coating was investigated by the Navicula Tenera and bacteria adhesion test. As a result, the high content of PSO paint has a high foul removal rate. The incorporation of PSO into paint can reduce the elastic modulus and surface energy of the coating to reduce its relative adhesion factor (RAF). The lower the RAF, the better the antifouling effect of the coating. The drag-reduction performance of the coating was verified by the torque selection experiment, and the results showed that incorporation of PSO into paint can enhance the elongation and hydrophobicity of the coating, thereby increasing the drag reduction rate of the coating.

Three-component waterborne silicone antifouling coatings, which could cured at room temperature, were prepared, respectively, with cationic (stearyl trimethyl ammonium bromide) or anionic (sodium dodecyl benzene sulfonate) silicone emulsion as a film-forming substance, &gamma, methacryloxypropyltrimethoxysilane as a curing agent and dibutyltin dilaurate as a catalyst. The effect of emulsifier on the structure and properties of silicone coating was studied. The results showed that the coating with cationic silicone emulsion had high crosslinking density, and its surface is smooth. The surface of the coating prepared by the anionic silicone emulsion is rough. Emulsifier type had no obvious effect on the surface free energy of the waterborne silicone coating. The coatings have the characteristics of low surface energy and excellent bacterial desorption properties. Stearyl trimethyl ammonium bromide in the cured coating can reduce the adhesion of marine bacteria on the coating surface. Both the emulsifiers can inhibit the activity of Navicula Tenera. The waterborne silicone coating prepared by cationic silicone emulsion has better comprehensive mechanical properties and antifouling performance.

This study addresses the issue of enhancing the mechanical properties and adhesion of silicone antifouling coatings. In this paper, &gamma, aminopropyltriethoxysilane was used to pretreat bisphenol A epoxy resin to obtain epoxy-silicone prepolymer, which was then mixed with hydroxyl-terminated polydimethylsiloxane to obtain epoxy-modified silicone. It was cured with polyamide curing agent and dibutyltin dilaurate catalyst to form film, and a three-component epoxy-modified silicone coating was prepared. Fourier transform infrared (FTIR) spectroscopy was used to characterize its chemical structure. The effects of epoxy content on the surface properties, mechanical properties and antibacterial properties of the coatings were characterized by confocal laser scanning microscope (CLSM), contact angle measurements, tensile test and bacterial adhesion test. The results show that adding epoxy makes the adhesion of the coating at level 1 and the surface free energy of the coating was between 15&ndash, 21 mJ/m2. When its content is less than 22.1 wt %, the coating is in a ductile material state. Once it is higher than 22.1 wt %, the coating was in a brittle material state. As the content increases, material&rsquo, s hardness and fracture strength increases, elastic modulus decreases first and then increases, but bacteria removal rate decreases. The modification of the epoxy to silicone can effectively improve the adhesion and mechanical properties of the coating, while maintaining the characteristics of the low surface of the coating. It plays a positive role in improving the performance of silicone antifouling coatings.

In this study, phenylmethylsilicone oil (PSO) with different viscosity was used for research in fouling release coatings based on polydimethylsiloxane (PDMS). The surface properties and mechanical properties of the coatings were investigated, while the leaching behavior of PSO from the coatings was studied. Subsequently, the antifouling performance of the coatings was investigated by the benthic diatom adhesion test. The results showed that the coatings with high-viscosity PSO exhibited high levels of hydrophobicity and PSO leaching, while the high PSO content significantly decreased the elastic modulus of the coatings and prolonged the release time of PSO. The antifouling results indicated that the incorporation of PSO into coatings enhanced the antifouling performance of the coating by improving the coating hydrophobicity and decreasing the coating elastic modulus, while the leaching of PSO from the coatings improved the fouling removal rate of the coating. This suggests a double enhancement effect on the antifouling performance of fouling release coatings based on PDMS with PSO incorporated.

Oxidation behavior of highly transparent Y-α-SiAlON ceramics with high nitrogen content ( n = 1.0) and lowered Y/Si ratio (0.041) at 1200–1400 °C within 32 h was investigated by measuring its phase assemblage, elemental composition and weight gain during oxidation process. Comparing to the reported Y-α-SiAlON, the obtained one has a lower oxidation rate at 1200 °C and 1300 °C. Oxidation rate at 1400 °C before 16 h is equivalent to the reported rate at 1300 °C. Improvement of oxidation resistance of the obtained Y-α-SiAlON characterized by single-crystalline phase and high density is attributed to its high nitrogen content and lowered Y/Si ratio.

Fluorinated acrylate quadripolymer (QPFA), acrylate bipolymer (BPFA), and acrylate homopolymer (HPFA) were synthesized by free radical polymerization using different monomers. The three fluoropolymers (5%) were mixed respectively with acrylic varnish, and HPFA at different concentrations (1, 3, 5, 7, and 10 wt%) was mixed with acrylic varnish. The polymer films were characterized by differential scanning calorimetry, X-ray diffraction, water absorption rates, and contact angle analyses; the coatings were characterized by confocal laser scanning microscopy, mechanical analyses, water contact angles, water absorption rates, and biofouling analyses. Results indicate that the three coatings containing different fluoropolymers have comparable mechanical properties. The QPFA coating featured the lowest resistance to benthic diatom adhesion because of its low fluorine content. With increasing fluorine contents, the mechanical properties of the HPFA coatings decreased. However, the contact angles and resistance to adhesion increased. Though the HPFA particles lowered adhesion between the matrix and coating, they simultaneously generated rough surfaces.

Waterborne silicate composite coatings were prepared to replace existing solvent-based coatings for ships. A series of complex coatings were prepared by adding anticorrosive pigments to the silicate resin. Adhesion, pencil hardness, and impact resistance were investigated, and corrosion performance in 3.5% NaCl solution was measured by electrochemical impedance spectroscopy (EIS). The results show that adhesion and impact resistance are high, and that pencil hardness can reach 4H. The curing mechanism for the coatings were investigated by Fourier-transform infrared spectroscopy (FTIR) and X-ray diffraction (XRD). The mechanism of curing reaction in the studied waterborne silicate paint was found to be different from that reported in the literature. When the coatings were immersed in 3.5% NaCl solution for 8 h, there is only one time constant in the Bode plot, and coating capacitance (Qc) gradually increases while coating resistance (Rc) gradually decreases. Glass flake composite coatings have better corrosion resistance by comprehensive comparison of Qc and Rc.