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The lubrication needs of wind turbines vary with the operating conditions. To provide a dynamic lubrication scheme for wind turbines under variable conditions, this paper designs a dynamically adjustable lubrication scheme through parallel control of multiple influencing factors. Based on mid- and long-term loads, the proposed scheme fully considers the influence of various sudden changes in addition to slowly changing factors like load, operating hours, and speed, such as to dynamically adjust the injection flow as per the specific operating condition of the turbine. The ideal lubrication effect was tracked through the adjustment of the injection flow or injection time, and used to determine the optimal dynamic lubrication control strategy during turbine operation. The proposed control strategy overcomes the defects of the traditional fixed-time fixed-flow lubrication approach, and provides reasonable on-demand lubrication schemes for wind turbines in different operating conditions. The on-demand injection of lubricant prevents under- or over-lubrication, reduces the rate of mechanical failure, and extends the service life of wind turbines. Suffice it to say that the proposed control strategy can lower power generation cost and save energy, making wind turbines more profitable.

The separation of surfactant-stabilized oil-in-water emulsions is a challenging issue as such state-of-art technologies usually suffer from energy-intensive, time-consuming, and inefficient process...

The Mg-5Al-2Ca alloys reinforced by 2vol%, 5vol% and 10vol% 5 μm SiCp were fabricated by stir casting. The cast composites were subject to hot extrusion. In the cast composites, addition of SiCp disturbs the network distribution of Al2Ca phase along grain boundaries. After extrusion, grains of the matrix are refined further and the Al2Ca phase break into particulates. Moreover, the Al2Ca phase and grain size can be further refined by the addition of SiCp. Compared with Mg-5Al-2Ca alloy, the addition of SiCp introduces obvious improvement of tensile yield strength (TYS) and work hardening rate, however, at the expense of elongation. Unlike the TYS, the ultimate tensile strength (UTS) of SiCp/Mg-5Al-2Ca composite does not change monotonously with increasing SiCp's content, and the highest UTS appears when the SiCp's volume fraction is 5%. The interfacial debonding between SiCp and Al2Ca phase and cracked particles are considered as the main crack source for SiCp/Mg-5Al-2Ca composite.

A Zn(II)-mediated pyridinium-bearing coordination polymer has been successfully synthesized and structurally characterized. The title compound exhibits rapid photochromic properties due to proper structural arrangement of the electron donor and acceptor for PET reaction. Besides, it also displays luminescence switching under the irradiation of 365 nm light.

Herein, a nickel coordination polymer (CP 1), {Ni(1,4-bib)1.5(TPA-Cl2)·H2O}n (1,4-bib = 1,4-bis(1H-imidazol-1-yl)benzene, H2TPA-Cl2 = 2,5-dichloro-terephthalic acid), has been synthesized under solvothermal conditions. The structure of CP 1 is a 3D 3-fold interpenetrating framework with the sqc12 topology. The thermal stability and luminescence properties of CP 1 were investigated. Scanning electron microscopy (SEM) images of this material display that it possesses an irregular block 3D structure. Interestingly, CP 1 can serve as a multifunctional material via its luminescence sensing, electrochemical sensing, and photocatalytic properties. The experimental results indicate that CP 1 is an efficient luminescent sensor for the detection of Fe3+ ions in an aqueous solution. In addition, CP 1 exhibits a sensitive and rapid electrochemical response to nitrite ions in water solution. The photocatalytic activities of CP 1 were evaluated in the degradation of different dye contaminants (MB, RhB, and MO), and the results demonstrate that its photocatalytic efficiency for the degradation of MB is highest (92.1% for MB, 85.7% for RhB, and 86.2% for MO). The effects of different dyes, different powers of UV light, and different amounts of catalyst CP 1 on the photocatalytic efficiency were also explored. Finally, the mechanism of the luminescence quenching effect toward Fe3+ ions, electroreduction of nitrite ions, and photocatalytic degradation of different dyes have been investigated in detail.

The hydrothermal reactions of 1,2,4,5-cyclohexanetetracarboxylic acid (H4L) with CoCl2·2H2O and rigid or semi-rigid bis(imidazole) ligands were able to generate two Co(ii) coordination polymers (CPs), {[Co5(L)2(1,4-bimb)(μ3-OH)2(H2O)8]·2H2O}n (1), {[Co(L)0.5(1,4-bib)]·H2O}n (2) (1,4-bimb = 1,4-bis(imidazol-1-ylmethyl)benzene, 1,4-bib = 1,4-bis(1H-imidazol-1-yl)benzene). CPs 1 and 2 were structurally characterized by elemental analysis, IR spectroscopy, X-ray powder diffraction and single crystal X-ray diffraction. CP 1 features a 3D 3,3,4,4,5-connected framework with an unprecedented {42·8·102·12}{43·6·86}2{43}2{46}2{62·8}2 topology, which represents the first example of CPs with such a topology. CP 2 possesses a three-fold interpenetration 3D framework with mog topology. The distinct structures of the two CPs may result from diverse coordination modes of the (L)4- ligands and different structural characteristics of rigid or semi-rigid N-donor ligands. The thermal stabilities, photoluminescence properties and electrochemical behavior in the solid state for CPs 1 and 2 have been investigated. The photophysical studies indicated that CPs 1 and 2 are potential semiconductive materials. Moreover, both CPs 1 and 2 show high photocatalytic efficiency for the degradation of methylene blue (MB) under UV light irradiation and exhibit good stability and recyclability. A possible photocatalytic mechanism is speculated by introducing t-butyl alcohol (TBA) as a widely used ˙OH scavenger.

Metal particle could be produced in the production and installation process of GIS, whose free movement is a significant security risk to GIS. At present, some related research focus on the movement behavior and partial discharge of individual particle, but for the movement behaviors and harmfulness of multiple particles are not very clear. In this paper, the 126 kV GIS prototype proportion shrinking test chamber was set up, the different number of metal particles with same size (10 mm length, 0.25 mm radius) were placed in the chamber, the movement behaviors of multiple particles were filmed by using a high speed camera, and discharge signals were recorded with the conventional pulse current detector and ultrasonic detector. The results of the study indicate that: At the operated voltage, the single particle (10 mm length, 0.25 mm radius) has a small jumping height but a high jumping frequency, and there is basically a collision case in each power frequency cycle. The number of linear particles affect the lifting voltage, and with the increase of the number of neighboring particles, the lifting voltage decrease, such as the lifting voltage of two aluminum particles with 10mm length and 0.25 mm radius could be reduced to 84% of the lifting voltage of a single particle, and the lifting voltage of eight aluminum particles could be reduced to 77%. Compared with single particle, the number of ultrasonic signals and partial discharge pulses of multiple particles becomes more obvious, and it could occur multiple collisions in a half power frequency cycle, but for a single particle, the maximum number of linear particle's collision in a half power frequency cycle is only one. With the increase of applied voltage, the flight time of the particles were significantly longer, and multiple discharge pulses were detected during a single collision, whose position showed “V” type distribution. At the operated voltage, the single linear particle had less harmfulness, while the existence of multiple linear particles, could greatly reduce the insulation strength of GIS, such as eight neighboring aluminum particles with 10 mm length and 0.25 mm radius could lead to a breakdown in the vicinity of the operated voltage, but the same size of the individual particle has not yet led to the breakdown of the test chamber at even twice of operated voltage. Under the different voltages, the maximum value of histogram of n-T/2 of linear particles remained unchanged, and through the histogram of n-T/2, it could estimate the number of particles in GIS.

Surface modification based on a photo-induced electron transfer (PET) reaction in a pyridinium-decorated MOF material was found to be effective in regulating adsorption capacity. The current system enables the adsorption behavior to be manipulated based on variable affinity toward guest molecules through the redistribution of charge population with the preservation of the original pore structure, which is different from the prevalent approaches depending on photoinduced changes in molecular configurations of the pore backbone.

We prepared intercalated organic montmorillonite (OMMT) from a pristine MMT and long-alkyl-chain quaternary ammonium salts (LACQAS). X-ray diffraction, Fourier transform infrared spectroscopy, scanning electron microscopy, and thermogravimetric analyses revealed that the amount, carbon atoms, and alkyl chains of LACQAS influenced the large value of d(001) of OMMT significantly. The d(001) stabilized at 100–150 mmol·(100 g)-1 of LACQAS/MMT. The single LACQAS cations arranged in the form of a lateral layer or half-paraffin-type molecular structure between MMT layers, whereas the dual and triple LACQAS cations arranged in the form of a paraffin-type molecular structure. The pyrolysis temperature and maximum pyrolysis rate of OMMT increased greatly compared with those of MMT. The thermal weight loss of MMT was caused by the removed absorbed and structural water, whereas that of OMMT was by the pyrolysis of LACQAS. With the help of the Agrawal integral equation, the pyrolysis kinetics of MMT and OMMT were obtained using a trial-and-error method.

In this study, microwave plasma was used to treat the surface of Pinus yunnanensis wood under the conditions of 220 V of input voltage, 20 μA of filament current, 8.8 mW of output power, 11 mW of reflected power, 2450 MHz of frequency, and 700 Pa of vacuum. The microwave plasma presented very significant treatment effects on the treated surface, even under weak treatment conditions, for example long treatment distance of 120 mm and short treatment time of 60 s. The treated surface showed better surface wettability, and the contact angles on the treated surface measured from deionized water, glycerin, and diiodomethane decreased sharply, even decreased to 0°. The treated surface also presented higher surface free energy, for example, 61.4–62.8 mJ m−2, being greatly improved by microwave plasma compared to that of untreated surface of 46.5 mJ m−2. The bond strength of the treated surface was 7.34 MPa, about 16 % higher than 6.31 MPa for untreated surface. The best treatment effect was obtained for the treatment distance of 120 mm and treatment time of 60–300 s. This technique might be widely used in wood modification and wood processing.

A high-speed data exchange network based on multimode fiber and RapidIO technology is widely used in existing projects. It consists of a fiber switch and a high-speed interface module. The fiber switch is used as the data exchange core to complete protocol conversion. The high-speed interface module is connected to the universal device node and is responsible for access conversion of the RapidIO bus between the optical network. The hardware design utilizes the commercial shelf architecture, the software design adopts a multi-buffer and multi-thread data exchange method to increase the entire network bandwidth from 300MB/s to 800MB/S.

In this study, vinyl acetate, N-hydroxymethyl acrylamide (NMA), and organic montmorillonite intercalated by a dioctadecyl dimethyl ammonium bromide surfactant (MMT-DOAB) were used to prepare exfoliated nanocomposites through in situ polymerization. Wide-angle X-ray diffraction, Fourier transform infrared spectroscopy, transmission electron microscopy, power-law function equation, Newtonian fluid flow equation, Cross–Williamson model viscous equation, Hooke's law, and Poisson's ratio equation revealed the structures, dispersion, rheology, and static tensile properties. The exfoliated nanocomposites were pseudoplastic non-Newtonian fluids with good dispersion in water, great storage stability, and high static tensile strength at 6.89–8.15 MPa. The contents of NMA and MMT-DOAB increased with the changes in synthesis precursors, as the calculated molecular weights did.

In this study, we prepared high-performance printable, stretchable electrical conductor from waterborne polyurethane and micro-silver flakes. The solidification and thermal degradation were investigated using differential scanning calorimetry and thermogravimetric analysis methods. The electrical conductor achieved solidification by volatilizing and removing the free water. The thermal degradation mainly happened in the range of 250–450 °C caused by the pyrolysis of the polymeric matrix of polyurethane. The pyrolysis kinetic equations were obtained using the kinetic methods, e.g., dα/dt = e22.16(1 − α)0.78α0.13e(−149.14/RT) for the polyurethane, dα/dt = e22.76(1 − α)0.84α0.11e(−150.69/RT), dα/dt = e21.43(1 − α)0.77α0.06e(−143.77/RT), and dα/dt = e19.06(1 − α)0.75α0.12e(−130.53/RT) for the electrical conductor containing 80, 85, and 90 % mass percentage of micro-silver flakes, where α was the fractional extent conversion at a given time t (or a given temperature T). Their overall order of reaction was 0.91, 0.95, 0.83, and 0.87, respectively, less than 1, demonstrating the thermal degradation was a single, simple reaction.

Large scale nonlinear elastic deformation behavior is induced by moderate precipitation of nano-scale α phase for Ti–25Nb–3Zr–2Sn–3Mo alloy after a strategy of cold rolling and short-time aging. Quantitive relationships are established between volume fraction of α phase (Vα) and elastic modulus, strength as well as maximal recoverable strain (emax-R), where the highest emax-R of 2.25% with strength of 900 MPa corresponds to Vα of 10%. With the Vα increasing, the elastic behavior transforms from “double yielding” to nonlinear elasticity and then normal linearity. It is considered that the nonlinear elasticity of the studied (α+β) microstructure is probably related to “mechanical” stabilization of the alloy, i.e. a blocking effect of α phase on the lattice shear from body-centered cubic β phase to orthorhombic-α″ martensite.

In this study, we combined silver nanowires with cupro fabrics using a dipping-drying method to prepare electrically conductive fabrics. The silver nanowires were first adhered to and then absorbed by microfibers to form electrically conductive fibers. They also filled the gaps and spaces between the microfibers, and were stacked or piled together to form networks with high electrical conductivity. The electrically conductive fabric had low resistance and good stretchability, e.g., 0.0047–0.0091 Ω in the strain range of 0–190%. They also exhibited stable electrical conductivity, as well as excellent flexibility, which remained even when the fabric was stretched, shrunk, or bent. The results show that the electrically conductive fabric can be used as a smart textile, especially in fields associated with weaving, clothing, food products, lifestyle products, medicine, biology, electronics, aviation, and military equipment and accessories.

In this study, high performance electrically conductive adhesives were fabricated from a vinyl ester resin, a thermal initiator, silver coated copper powders, and pure silver powders, without using any other coupling agent, dispersing agent, and reducing agent. The heat cured copper-silver powders filled electrically conductive adhesives presented low bulk resistivity (e.g., 4.53 × 10−5 Ω·cm) due to the silver powders that had given high electrical conductivity to the adhesives, and high shear strength (e.g., 16.22 MPa) provided by the crosslinked structures of vinyl ester resin. These high performance copper-silver powders filled electrically conductive adhesives have lower cost than those filled by pure silver powders, which can be well used in the electronic packaging and can enlarge the application prospects of electrically conductive adhesives.

In this study, a thermal initiator of 1,1-bis(t-hexylperoxy)-3,3,5-trimethyl cyclohexane was introduced to thermally initiate the curing of vinyl ester resin, and then a dynamic differential scanning calorimetry method was applied to investigate the thermally initiated curing procedures. Thermally initiated by the thermal initiator under heating, the end double bonds of vinyl ester resin macromolecules were opened to accomplish the crosslinking, polymerizing, and curing. The increasing thermal initiator advanced the curing procedures and shifted the initial temperature, exothermic peak temperature, and final temperature to a low temperature zone. The curing kinetics of thermally initiated vinyl ester rein was studied using the Ozawa method and deduced by assuming a constant activation energy. The thermally initiated curing kinetic equations, e.g., dα/dt = e30.16(1 − α)2.88α0.01e−106.60/RT, dα/dt = e29.43(1 − α)2.72α0.16e−105.17/RT, dα/dt = e29.43(1 − α)2.85α0.03e−104.48/RT, dα/dt = e29.41(1 − α)2.87α0.01e−104.11/RT, dα/dt = e27.70(1 − α)2.64α0.05e−99.63/RT, and dα/dt = e26.26(1 − α)2.32α0.30e−96.16/RT, respectively corresponding to the weight ratios between the thermal initiator and the vinyl ester resin at 0.5:100, 1:100, 2:100, 3:100, 4:100, and 5:100, were obtained. The increasing thermal initiator significantly influenced the thermally initiated curing kinetic parameters, such as the exothermic peak temperature, the fractional extent conversion, the rate of conversion, the overall order of reaction, the activation energy, the preexponential factor, and the reaction rate constant, and the thermally initiated curing kinetic equations. The data calculated from the kinetic equation agreed well with the experimental data, showing that the Ozawa method could evaluate the curing kinetics effectively.

By adding 2 wt% multi-layer graphene oxide (MGO) to an epoxy resin, the thermal conductivity of the compos- ite reached a maximum, 2.03 times that of the epoxy. The presence of 2 wt%MGO percolating chains leads to an unprece- dentedly sharp rise in energy barrier at final curing stage, but an increased epoxy curing degree (!IR) is observed; however, this !IR difference nearly disappears after aging or thermal annealing. These results suggest that the steep concentration gra- dient of -OH, originated from the 2 wt%MGO percolating chains, exerts the vital driving force on the residual isolated/ trapped epoxy to conquer barrier for epoxy-MGO reaction. A modified Shrinking Core Model customized for the special layered-structure of MGO sheet was proposed to understand the resistance variation during the intercalative epoxy-MGO reaction. It shows that the promoted intercalative crosslinking is highly desirable for further improving the thermal conduc- tivity of the composite, but it meets with increased resistance. Guided by the kinetic studies, targeted optimization on the cure processing strategy was accordingly proposed to promote the intercalative crosslinking, a thermal conductivity, 2.96 times that of the epoxy, was got with only a small amount (30°C) increase of the post-heating temperature.

A biodegradable polyvinyl alcohol and silver nanowires (AgNWs) have been mixed together with a simple one-step blending method to form a hybrid electrical compositor. Super flexible and highly conductive electrical compositors were successfully developed with an AgNWs content of 80%, in which hundreds, even thousands of AgNWs stacked into a “Chrysanthemum petal” order to exhibit high electrical conductivity of 17 390 S cm−1. The high conductivity corresponded to the formation of a large amount of electrically conductive networks and channels. The conductively electrical compositor can be made into various shapes and can be used on any substrate with different curved surfaces because the compositor ink is so stable and can be stored for a long time without other additives. The compositor is expected to have great potential application in flexible electronics, especially in those fields associated with biology, medicine, food, and life.

In this study, the exfoliated montmorillonite was prepared through the click chemistry of a propargyl-containing intercalator with singly or multiply azido-functionalized polyhedral oligomeric silsesquioxane nanoparticles. Thermogravimetric analyses revealed that the pyrolysis kinetics had a close relationship to the layered structures, exfoliated structures, and cage-like molecules of polyhedral oligomeric silsesquioxane nanoparticles. The pyrolysis of exfoliated montmorillonite had a mechanism function of Avrami–Erofeev equation, and the kinetic compensation effect equation revealed the pyrolysis.

The effect of stray current and stress on corrosion of API X65 steel in simulated solution of the alkaline soil in Daqing in China was investigated using corrosion potential test, potentiodynamic polarization measurement, as well as surface analysis techniques. A mathematical relationship between corrosion rate and yield strength, direct current (DC) stray current density was obtained by multiple linear regression. The results demonstrate that, the corrosion potential of API X65 steel with and without superimposed DC stray current all shifted negatively, and the corrosion current density increases with the enhancement of tensile stress in solution. The corrosion current density under the synergistic effect of stress and stray current is much higher than corrosion current density that single factor (stress or stray current) induced. Comparing with the stress, the effect of stray current on corrosion rate of API X65 steel is more significant in elastic deformation. Mutation in corrosion potential and corrosion rate appeared when the strain reaches plastic deformation. This work provides reference suggestion for pipeline safety design and operation, where the corrosion enhancement due to the synergistic effect of stray current and stress should be considered.

Nanostructures of a new Co(II) coordination polymer (CP), [Co(Hbibp)(nbta)] n ( 1 ), (bibp = 4,4′-bis(1-imidazolyl)biphenyl, H 3 nbta = 5-nitro-1,2,3-benzenetricarboxylic acid) was synthesized by a sonochemical method. The nano-sized CP 1 was characterized by elemental analysis, IR spectroscopy, X-ray powder diffraction and scanning electron microscopy (SEM). Structural analysis show that CP 1 exhibits a 1D chain structure with a 3-connected SP 1-periodic net (4,4)(0,2) topology, which can be further extended into a 2D supramolecular layer by the N H⋯O hydrogen bond interactions. The thermal stability for CP 1 as bulk and nanoparticles were investigated. The photoluminescence properties and electrochemical behavior for nano-sized CP 1 have also been explored. Moreover, nano-sized CP 1 shows high photocatalytic activities for the degradation of MB under UV irradiation and the photodegradation process is mainly caused by OH radicals. Effects of the sonication time and ultrasonic power on the morphology and size of nanoparticles were studied.

In this study, the electrically conductive adhesives were fabricated using vinyl ester resin and micro silver flakes, and then a high-intensity pulsed light was introduced to cure the adhesives under an ambient atmosphere at room temperature. The thermal degradation kinetics of photonically cured products was studied using the Friedman method and deduced by assuming a variable activation energy (E). The value of E spanned from 110 to 233 kJ mol−1, which first increased, then decreased, and finally increased again as the thermal degradation proceeded. The kinetic equation of thermal degradation was obtained as dα/dt = e26.62(1 − α)2.22 α 1.85e(−E(α)/RT) with E(α) = 961.73α 3 − 1453.9α 2 + 669.79α + 79.859, α ∈ (0, 1), where α was the fractional extent conversion at a given time (or given temperature). The overall order of reaction was 4.07 and >1, demonstrating that the thermal degradation was complex. With the Friedman method, a comprehensive and in-depth understanding of the thermal degradation kinetics of photonically cured electrically conductive adhesives has been achieved.

In this paper, we fabricated electrically conductive adhesives using vinyl ester resin and micro silver flakes, and then cured the adhesives by heat without any catalysts or initiators. The curing temperature was above 200 °C, and the curing time about 30 min. Under these heat curing conditions, the double bonds in the adhesives reached a high conversion (α) around 98.88 % calculated from the Fourier transform infrared spectroscopy analysis. The curing kinetics of heat curing products was studied using Ozawa method and deduced by assuming a constant activation energy (E). The curing kinetic equation was obtained as dα/dt = e17.70(1 − α)1.19α0.41e(−94.32)/RT) with E = 94.32 kJ mol−1. The heat curing followed the shrinking core model from the resin-particle system. The data calculated from the kinetic equation agreed well with the experimental data, showing that the Ozawa method could evaluate the curing kinetics effectively. Furthermore, a comprehensive and in-depth understanding of the curing kinetics of heat curing electrically conductive adhesives has been achieved with this Ozawa method.

In this study, we introduced N-hydroxymethyl acrylamide and an organic montmorillonite intercalated by an octadecyl trimethyl ammonium bromide surfactant together into the in situ polymerization of polyvinyl acetate to form exfoliated nanocomposites. Wide-angle X-ray diffraction, Fourier transform infrared spectroscopy, transmission electron microscopy, power-law function equation, Newtonian fluid flow equation, Cross-Williamson model viscous equation, Hooke's law, and Poisson's ratio equation revealed the structures, dispersion, rheology, and static tensile properties. The exfoliated nanocomposites were pseudo-plastic non-Newtonian fluids, presented a good dispersion in water, a great storage stability, and a high static tensile strength at 6.78–8.06 MPa.

In this study, we synthesized a poly(N-isopropylacrylamide) (PNIPAm) through the polymerization of N-isopropylacrylamide in distilled water with azodiisobutyronitrile as the initiator and a bisadenine-functionalized poly(ethylene oxide) (A-PEO-A) from the reaction of adenine with a difunctionalized toluenesulfonyl-PEO. When blended together in distilled water, PNIPAm and A-PEO-A formed supramolecular aggregates stabilized through complementary multiple hydrogen bonds between the amide groups of PNIPAm and the adenine units of A-PEO-A. Agrawal integral equation and rheometry revealed the rheological kinetics of supramolecular assemblies, which were influenced significantly by the spherical micelles, large associated aggregates of spherical micelles, network structures, and toroid structures formed in aqueous solutions.

In this study, we used a singly azido-functionalized polyhedral oligomeric silsesquioxane (POSS) derivative and a montmorillonite intercalated by propargyldimethylstearylammonium bromide to prepare an exfoliated montmorillonite through click chemistry. This exfoliated montmorillonite was then introduced into a benzoxazine matrix prepared from paraformaldehyde, aniline, and phenol to form polybenzoxazine/exfoliated clay nanocomposites. Dynamic mechanical analysis, differential scanning calorimetry, and Agrawal integral equation revealed that the glass transition kinetics had a close relationship to the structure, assembly process, and anchoring effect of montmorillonite layers, the compatibility between polybenzoxazine and intercalator, and the methods of dynamic mechanical analysis and differential scanning calorimetry. The polybenzoxazine/exfoliated clay nanocomposites presented the same mechanism function at different weight ratios between polybenzoxazine and exfoliated clay, and the kinetic compensation effect equations revealed the nature of glass transition.

In this study, the montmorillonite (MMT) reinforced phenol formaldehyde (PF) resin intercalated nano-composite of PF–MMT was prepared from phenol, formaldehyde, and pristine MMT. We then introduced this PF–MMT into the production of plywood from Simao Pine veneers. Matrix assisted laser desorption ionization time of flight mass spectrometry (MALDI-TOF), wide-angle X-ray diffraction (XRD), differential scanning calorimetry (DSC), thermal mechanical analysis (TMA), and bonding strength revealed the related structure, curing, and mechanical properties. The thermoplastic PF with a linear structure entered the MMT layers and then formed the network structure after cured. The wet bonding strength and modulus of elasticity (MOE) of plywood were improved significantly. This preparation is simple and easy, and can be applied in the production of wood industry.

In this study, we synthesized a poly( N -isopropylacrylamide) (PNIPAm) through the polymerization of N -isopropylacrylamide in distilled water with azodiisobutyronitrile as the initiator and a bisadenine-functionalized poly(ethylene oxide) (A-PEO-A) from the reaction of adenine with a difunctionalized toluenesulfonyl-PEO. When blended together in distilled water, PNIPAm and A-PEO-A formed supramolecular aggregates stabilized through complementary multiple hydrogen bonds between the amide groups of PNIPAm and the adenine units of A-PEO-A. Fourier transform infrared spectroscopy, 1 H nuclear magnetic resonance spectroscopy, transmission electron microscopy, dynamic light scattering, and rheometry revealed the thermo-sensitive behavior and viscoelastic properties of the supramolecular assemblies.

In this study, we used 3-aminopropyltrimethoxysilane, hexanedioic acid, 3-mercaptopropyltrimethoxysilane, and thioglycolic acid to functionalize the surface of micro silver flakes through in-situ replacements. Hexanedioic acid had the best effect on the functionalization. When the content of hexanedioic acid was 0.5–1 wt% of micro silver flakes, it could fully replace the long chain fatty acid and form a very thin molecular film on the surface of micro silver flakes. The micro silver flakes functionalized by hexanedioic acid played a significant role in the regards of improving the properties of electrically conductive adhesives, and letting the adhesives have low viscosity, e.g., 28,000 cPs, low bulk resistivity, e.g., 2.4×10 −4 Ω cm, and high shear strength, e.g, 10.4 MPa.

To avoid high temperatures and long curing times, both of which are impractical in the manufacture of flexible printed electronic devices, we fabricated new electrically conductive adhesives using vinyl ester resin and silver micro-flakes and introduced an intense pulse of light to cure the adhesives under an ambient atmosphere at room temperature. The electrically conductive vinyl ester resin–silver micro-flake adhesives can absorb intense pulsed light, which initializes the double bonds in the resin to successfully achieve crosslinking and curing. This curing process, known as photonic curing, can be completed within a second under an ambient atmosphere at room temperature, over a large area. A typical curing time was 140 ms without any photosensitizers or photoinitiators in the adhesives. The cured conductive adhesives had low bulk resistivity, e.g., 7.54 × 10−6 Ω cm and high bonding strength, e.g., 6.75 MPa. Thus, the combination of photonic curing and electrically conductive vinyl ester resin–silver micro-flake adhesives has great potential for printed electronics, which require low temperature and fast processes based on flexible devices.

Two bis (benzimidazoyl) monomers were synthesized, and Poly (N-arylenebenzimidazole ketone) s were prepared by N-C coupling reaction that replaced the NH sites from the bis (benzimidazolyl) derivatives with activated difluorides monomers in sulfolane at 210 °C. All the resulting polymers showed easy solubility compared with traditional polybenzimidazoles. Differential scanning calorimetry and thermogravimetric measurements showed that the polymers had high glass transition temperatures (>240 °C), good thermostability and high decomposition temperatures (>460 °C).

In this study, we presented the use of polyurethane, ethylene-vinyl acetate hotmelt, and nano hexagonal boron nitride particles to prepare high surface adhesion polymer fibers via an elertrospinning method. The shear strength, dynamic tensile properties, and surface morphology have been investigated. These polymer fibers were found to have high shear strength, high tensile stress, and high tensile strain, which may have a good potential application in the matrix materials for thermal interface materials. Polymer fibers with and without nano hexagonal boron nitride particles showed the shear strength of 6.52 MPa and 5.44 MPa respectively on being heated up at 150°C for 45 min.

In this study, we prepared exfoliated nanocomposites from polyvinyl acetate (PVAc) and organic montmorillonite (OMMT) through different synthesis processes. OMMT was exfoliated into layers or sheets of nanoparticles. They dispersed in PVAc matrix randomly. The synthesis processes influenced the dispersion and apparent viscosity significantly. PVAc and PVAc–OMMT both were pseudo-plastic Non-Newtonian fluids and had the normal stress effect (or Weissenberg effect) from pole-climbing phenomenon. By analyzing the apparent viscosity using power-law function equation, Newtonian fluid flow equation, and Cross-Williamson model viscous equation, the synthesis processes and OMMT had a combined effect on the rheology of PVAc and PVAc–OMMT. With the change of synthesis processes and the increase of OMMT content in synthesis system, the calculated molecular weight of PVAc–OMMT increased.

Porous BN/Si 3 N 4 ceramics with spherical-shaped pore structures were prepared by gel casting, in which polymethylmethacrylate microsphere (PMMA) was used as pore-forming agent. Effect of PMMA size on microstructure, phase composition, mechanical and dielectric properties of the porous ceramics were investigated in detail. Pore structures in the fabricated BN/Si 3 N 4 ceramics are composed of both spherical-shaped micro pores depending on the diameter of starting PMMA and irregular sub-micro pores formed by stacking ceramic particles. The micro pores are homogeneously distributed in ceramic matrix, without “pore overlapping”, and the sub-micro pores are acted as the channels between micro pores. Phase composition, mechanical and dielectric properties of the obtained ceramics can be well controlled by the diameter of starting PMMA because of the different porosity and pore size. The composite with 10 wt.% starting PMMA (with the diameter of 10 μm) show flexural strength of 71.6 ± 4.5 MPa, and the dielectric constant is about 3.35 under different frequencies. The excellent mechanical and dielectric properties of the porous BN/Si 3 N 4 ceramics may attribute to the spherical-shaped pore structure.

In this study, novel fast-curing electrically conductive adhesives were prepared from a functional epoxy, a reactive diluent, a silane coupling agent, a curing agent, and micro silver flakes. Differential scanning calorimetry, Fourier transform infrared spectroscopy, four-probe method, shear test, impact test, scanning electron microscopy, and energy dispersive spectroscopy revealed the physical, electrical, mechanical, and thermal properties of these electrically conductive adhesives. They were cured at 120°C and 150°C for 15 min, and had low bulk resistivity, high shear strength, and low water absorption. They can be used in the electronic packaging and improve the related production efficiency greatly.

In this study, an exfoliated montmorillonite was prepared through click chemistry from a singly azido-functionalized polyhedral oligomeric silsesquioxane derivative and a montmorillonite intercalated with propargyldimethylstearylammonium bromide. This exfoliated montmorillonite was then introduced into a benzoxazine matrix—prepared from paraformaldehyde, aniline, and phenol—to form polymer/exfoliated clay nanocomposites. Thermogravimetric analysis revealed that the pyrolysis kinetics had a close relationship with the structure of montmorillonite, the assembly process, the anchoring effect, the compatibility of the polymer and intercalator, and the char yield. The polymer/exfoliated clay nanocomposites had a same mechanism function, and the kinetic compensation effect equations revealed the pyrolysis essences.

By gel casting with polymethylmethacrylate microbeads (PMMA) as pore-forming agent, porous boron nitride/silicon nitride (BN/Si3N4) composite ceramics were successfully prepared. The obtained ceramic shows bimodal hierarchical structures that composed of spherical-shaped micro pores depending on PMMA content and irregular sub-micro pores formed by the stacking of ceramic particles. Porosity of the porous BN/Si3N4 ceramics can be well controlled from 53.0 to 60.6 % by the PMMA content from 10 to 40 wt%, as well as the mechanical and dielectric properties. Effect of PMMA content on phase composition and the relationship between microstructure and the basic properties of the porous BN/Si3N4 ceramics was discussed in detail. Microstructure analysis reveals that the sub-micro pores acted as channels between micro pores. BN particles have a relatively denser distribution on the wall of spherical-shaped micro pores with a window between micro and sub-micro pores, and resulting in a half-closed micro pore structure, which is meaningful for material design with concentration of BN particles on the wall of pore structure.

To develop high performance electrically conductive adhesives (ECAs), bi-modal ECAs were prepared by a matrix resin, micron silver flakes and micron silver spheres, and tri-modal ECAs were prepared by a matrix resin, micron silver flakes, micron silver spheres and acidified single wall carbon nanotube (ASWCNT). With the increase of nano silver spheres, the bulk resistivity of bi-modal ECAs decreased firstly and then increased while tri-modal ECAs' bulk resistivity firstly increased and then decreased with the increase of ASWCNT due to different electrically conductive channels were formed in them. After aged for 500 h under humid and thermal cycle of constant humidity level of 85% relative humidity at 85 °C, the contact resistance shift of bi-modal ECAs was more than 20% and that of tri-modal ECAs was less than 15% showing tri-modal ECAs had lower and more stable contact resistance. The humid and thermal surroundings had bad effect on the mechanical properties of bi- and tri-modal ECAs, after aged for 500 h, they both were reduced about 50–65%. And a bi-modal ECAs and a tri-modal ECAs were optimized and investigated in detail which can be used in electronic packaging.

In this study, we incorporated micro-silver flakes and nano-hexagonal boron nitride (BN) particles into a matrix resin to prepare electrically conductive adhesives (ECAs). The humid and thermal aging results under a constant relative humidity level of 85% at 85 °C revealed that the aged ECAs containing 3 wt% of nano-hexagonal BN particles had high reliability. The contact resistance was low and the shear strength high. Nano-hexagonal BN particles have a good effect on the reliability of ECAs that can be used to improve the properties of ECAs.

Five different processes were designed based on the polymerization time and water amount to investigate their influence on the properties of exfoliated nanocomposites synthesized by vinyl acetate (VAc) and montmorillonite-octadecyl trimethyl ammonium bromide (MMT-STAB). The violent stirring, low MMT-STAB content, high polymerization temperature, favorable polymerization time and suitable water amount were very important. PVAc-MMT-STAB had high static tensile and good dispersion. PVAc's linear macromolecular chains were formed in MMT-STAB layers that was exfoliated into layers or sheets of nanoparticles and dispersed randomly. They dispersed together to form the structures of “Strawberry,” “Swallow,” “Tactoids,” “Half Core-Shell” and “Similar Core-Shell”.

In this study, a matrix resin containing a functional epoxy, a reactive diluent, a silane-coupling agent, and a curing agent was used to fabricate three modal electrically conductive adhesives (ECAs) with micron silver flakes, nano silver spheres, and treated single-wall carbon nanotubes (CNT). Results showed that too many micron silver flakes reduced the bulk resistivity and adhesion strength of uni-modal ECAs (matrix resin and micron silver flakes). As the nano silver spheres increased, the bulk resistivity of bi-modal ECAs (matrix resin, micron silver flakes, and nano silver spheres) firstly decreased, and then increased again. The adhesion strength decreased also. The bulk resistivity and adhesion strength of tri-modal ECAs (matrix resin, micron silver flakes, nano silver spheres, and treated CNT) both were reduced by the treated CNT greatly. These ECAs could be cured at 120°C or any higher temperature than this with different curing time. They all had high temperature stability with a pyrolysis temperature above 350°C and a glass transition temperature around 180°C.

h-BN/Si3N4 composite ceramics were fabricated by gel-casting method and pressureless sintering using Si3N4 and h-BN as raw materials. The effect of h-BN on the microstructure and comprehensive properties of h-BN/Si3N4 ceramic were investigated. The results showed that the introduction of h-BN hindered the densification of h-BN/Si3N4 ceramic as well as the transformation of α-Si3N4 to β-Si3N4. The mechanical properties of Si3N4 based ceramics decreased with the increase of h-BN content, while the thermal property, dielectric properties and machinability increased.

It is very helpful to guide design production and processing conditions for polymer-based inorganic or organic nano-composites by investigating their rheology. In this study, an intercalated nano-composite of montmorillonite (MMT)-dioctadecyl dimethyl ammonium bromide (DOAB) was added and reacted with vinyl acetate (VAc) to form the exfoliated nano-composite of polyvinyl acetate (PVAc)–MMT–DOAB through five different synthesis processes. The MMT–DOAB was exfoliated into nano-particles of layers or sheets and dispersed randomly in PVAc matrix. The different synthesis processes affected the dispersion and apparent viscosity of PVAc and PVAc–MMT–DOAB. With the polymerization time shortening and the water decreasing, the dispersion got bad and the apparent viscosity increased. PVAc and PVAc–MMT–DOAB were pseudo-plastic non-Newtonian fluids and both possessed the normal stress effect (Weissenberg effect) that is also called the pole-climbing phenomenon. By the help of the apparent viscosity analyzed using the power-law function equation, Newtonian fluid flow equation and Cross-Williamson model viscous equation, the different synthesis processes and MMT–DOAB had a certain effect on the rheology of PVAc and PVAc–MMT–DOAB. With the change of different synthesis processes and the increase of MMT–DOAB content in the synthesis system, the estimated molecular weight of PVAc–MMT–DOAB was also increased accordingly.