Preparation, Characterization and Frictional Properties of Silane Self-Assembled Elastomeric Nanocomposite Polymer Layers

A novel surface modification method was proposed to improve the tribological property of Si. Multilayers were grown on Si（100） substrate by self-assembling monolayer （SAMs） method and filtered catholic vacuum arc （FCVA） technique. The film composition and structure were characterized by using x-ray photoelectron spectroscope （XPS） and Raman spectroscopy （Raman）. Surface morphology and the roughness were also analyzed by an atomic force microscope （AFM） and a scanning electron microscopy （SEM）. The frictional behaviors of the films were evaluated by a UMT tester. Results showed that elastomeric nanocomposite monolayer prepared by SAM was uniformly distributed and isotropy, and the diamond-like carbon （DLC） film was successfully deposited by the FCVA technique. The friction coefficients of the prepared samples were in the range of 0.108-0.188. Furthermore, the friction coefficient slightly increased but the surface quality of the wear trace was improved after adding the copolymer elastomeric macromolecules SEBS on aminopropyl-triethoxysilane （APS） layer due to the inherent long chain of SEBS which abated the immediate impulsion at the interface and changed the kinetic energy into elastic potential energy, and stored it in SEBS.

Boosting the cycling stability of all-solid-state lithium metal batteries through MOF-based polymeric protective layers

Solid-state electrolytes(SSEs)play a pivotal role in advancing next-generation lithium metal battery technology.However,they commonly encounter substantial interfacial resistance and poor stability when interfacing with lithium metal,hindering practical applications.Herein,we introduce a flexible metal-organic framework(MOF:NUS-6)-incorporated polymeric layer,denoted as NP,designed to protect the sodium superionic conductor(NASICON)-type Li_(1.3)Al_(0.3)Ti_(1.7)(PO_(4))_(3)(LATP)electrolyte from Li metal anodes.The NP matrix establishes a soft interface with the LATP surface,effectively reducing voids and gaps that may arise between the LATP electrolyte and Li metal.Moreover,the MOF component in NP enhances ionic conductivity,offers abundant Li^(+)transport sites,and provides hierarchical ion channels,ensuring a homogeneous Li^(+)flow and thus effectively inhibiting Li dendrite formation.Utilizing NP,we fabricate Li symmetrical cells cycled for over 1600 h at 0.2 mA cm^(-2)and all-solid-state LiINP-LATPI LiFePO_(4)batteries,achieving a remarkable 99.3%capacity retention after 200 cycles at 0.2 C.This work outlines a general strategy for designing long-lasting and stable solid-state Li metal batteries.

High-performance sandwiched hybrid solid electrolytes by coating polymer layers for all-solid-state lithium-ion batteries

Poly(vinylidenefluoride-co-hexafluoropropylene)(P(VDF-HFP))/Li_(1.3)Al_(0.3)Ti_(1.7)(PO_(4))_(3)(LATP)/P(VDFHFP) sandwiched hybrid solid electrolytes were precisely tailored and successfully fabricated to assemble into allsolid-state lithium-ion batteries,which were systematically evaluated on microstructure,morphology,thermal stability and electrochemical performance.The sandwiched hybrid solid electrolytes can achieve intimate contact with cathode and anode electrodes to present an excellent interfacial stability.Furthermore,the sandwiched hybrid solid electrolytes possess flexible surface,wide electrochemical working window of 4.7 V,high ionic conductivity of 0.763 mS·cm^(-1) and high thermal stability of 460℃,which may contribute to realizing the practical application in all-solid-state lithium-ion batteries.The assembled cells with the hybrid solid electrolytes can quickly stabilize at a specific discharge capacity of 145.4 mAh·g^(-1) at 0.1 C after only 5 cycles and present admirable rate performance.In addition,morphology characterizations of the sandwiched hybrid solid electrolytes after long-term cycles show a relatively integrated structure coating with a compact LATP layer.The investigations afford a promising strategy that the sandwiched hybrid solid electrolytes can overcome the mechanical limitations of the interface between electrodes and inorganic solid electrolytes to provide favorable properties for all-solid-state lithium-ion batteries.

Air tightness of compressed air storage energy caverns with polymer sealing layer subjected to various air pressures

During the operation of compressed air storage energy system,the rapid change of air pressure in a cavern will cause drastic changes in air density and permeability coefficient of sealing layer.To calculate and properly evaluate air tightness of polymer sealing caverns,the air-pressure-related air density and permeability must be considered.In this context,the high-pressure air penetration in the polymer sealing layer is studied in consideration of thermodynamic change of the cavern structure during the system operation.The air tightness model of compressed air storage energy caverns is then established.In the model,the permeability coefficient and air density of sealing layer vary with air pressure,and the effectiveness of the model is verified by field data in two test caverns.Finally,a compressed air storage energy cavern is taken as an example to understand the air tightness.The air leakage rate in the caverns is larger than that using air-pressure-independent permeability coefficient and air density,which is constant and small in the previous leakage rate calculation.Under the operating pressure of 4.5-10 MPa,the daily air leakage in the compressed air storage energy cavern of Yungang Mine with high polymer butyl rubber as the sealing material is 0.62%,which can meet the sealing requirements of compressed air storage energy caverns.The air tightness of the polymer sealing cavern is mainly affected by the cavern operating pressure,injected air temperature,cavern radius,and sealing layer thickness.The cavern air leakage rate will be decreased to reduce the cavern operating pressure the injection air temperature,or the cavern radius and sealing layer thickness will be increased.

Layered Foam/Film Polymer Nanocomposites with Highly Efficient EMI Shielding Properties and Ultralow Reflection

Lightweight,high-efficiency and low reflection electromagnetic interference(EMI)shielding polymer composites are greatly desired for addressing the challenge of ever-increasing electromagnetic pollution.Lightweight layered foam/film PVDF nanocomposites with efficient EMI shielding effectiveness and ultralow reflection power were fabricated by physical foaming.The unique layered foam/film structure was composed of PVDF/SiCnw/MXene(Ti_(3)C_(2)Tx)composite foam as absorption layer and highly conductive PVDF/MWCNT/GnPs composite film as a reflection layer.The foam layer with numerous heterogeneous interfaces developed between the SiC nanowires(SiCnw)and 2D MXene nanosheets imparted superior EM wave attenuation capability.Furthermore,the microcellular structure effectively tuned the impedance matching and prolonged the wave propagating path by internal scattering and multiple reflections.Meanwhile,the highly conductive PVDF/MWCNT/GnPs composite(~220 S m^(−1))exhibited superior reflectivity(R)of 0.95.The tailored structure in the layered foam/film PVDF nanocomposite exhibited an EMI SE of 32.6 dB and a low reflection bandwidth of 4 GHz(R<0.1)over the Kuband(12.4-18.0 GHz)at a thickness of 1.95 mm.A peak SER of 3.1×10^(-4) dB was obtained which corresponds to only 0.0022% reflection efficiency.In consequence,this study introduces a feasible approach to develop lightweight,high-efficiency EMI shielding materials with ultralow reflection for emerging applications.

Synthesis and Crystal Structure of a Novel Two-dimensional Layered Polymer [Zn(μ-O_2CCH=CHCO_2)(C_3H_4N_2)(H_2O)]_n

The title complex [Zn(-O2CCH=CHCO2)(C3H4N2)(H2O)]n was prepared by the reaction of zinc carbonate with maleic acid and imidazole in an aqueous-alcohol solution at 333 K, and its crystal structure has been solved by single-crystal X-ray diffraction. The complex crystallizes in the monoclinic system, space group Pc with a = 5.3858(7), b = 22.685(3), c = 7.6782(1) ? = 92.261(2)o, V = 937.4(2) 3, Z = 1, C14H16N4O10Zn2, Mr = 531.05, Dc = 1.882 g/cm3, = 2.623 mm1, F(000) = 532, the final R = 0.0372 and wR = 0.0930 for 1926 observed reflections with I>2s(I). The central zinc atom is five-coordinated in a distorted square pyramidal environment to three oxygen atoms of two different maleate ligands, a nitrogen atom of the imi- dazole ligand and an oxygen atom of water. In the complex two carboxylate groups of the maleate ligands have two coordination modes. One acts as a bidentate chelate ligand and the other a monoatomic monodentate ligand to bridge two zinc centers. As a result, 1-D infinite polymeric chains are formed, which are linked together by pairs of OH…O hydrogen bonds between the coordination water OH groups and carboxylate oxygen atoms to construct a 2-D layered polymer, and the layer structure is stabilized by p-p stacking of the imidozel ligands.

Effect of Crystallinity of Fullerene Derivatives on Doping Density in the Organic Bulk Heterojunction Layer in Polymer Solar Cells

Polymer solar cells （PSCs） based on poly（3-hexylthiophene） （P3HT） and [6,6]-phenyl-C61-butyric acid methyl ester （PCBM） are fabricated by using 1,8-diiodooctane （DIO） as a solvent additive to control the doping density of the PSCs. It is shown that the processing of DIO does not change the doping density of the P3HT phase, while it causes a dramatic reduction of the doping density of the PCBM phase, which decreases the doping density of the whole blend layer from 3.7 × 10^16 cm-3 to 1.2 ×10^16 cm-3. The reduction of the doping density in the PCBM phase originates from the increasing crystallinity of PCBM with DIO addition, and it leads to a decreasing doping density in the blend film and improves the short circuit current of the PSCs.

Atomic layer deposition of ultrathin layered TiO_2 on Pt/C cathode catalyst for extended durability in polymer electrolyte fuel cells

This study shows the preparation of a TiO2 coated Pt/C（TiO2/Pt/C） by atomic layer deposition（ALD）,and the examination of the possibility for TiO2/Pt/C to be used as a durable cathode catalyst in polymer electrolyte fuel cells（PEFCs）. Cyclic voltammetry results revealed that TiO2/Pt/C catalyst which has 2 nm protective layer showed similar activity for the oxygen reduction reaction compared to Pt/C catalysts and they also had good durability. TiO2/Pt/C prepared by 10 ALD cycles degraded 70% after 2000 Accelerated degradation test, while Pt/C corroded 92% in the same conditions. TiO2 ultrathin layer by ALD is able to achieve a good balance between the durability and activity, leading to TiO2/Pt/C as a promising cathode catalyst for PEFCs. The mechanism of the TiO2 protective layer used to prevent the degradation of Pt/C is discussed.

A Polymer Flooding Pilot in Thin Layers of Non-essential Reservorirswith Medium-low Permeability and Heterogeneity in Daqing

DaqingOilfieldisalargeinlandfluvialdelta-lacustrinesedimentationreservoirwithmulti-layersandhighreservoirheterogeneity.Fromnorthtosouththereare7localstructuresinDaqingOilfield,andverticallythereare3setsofoil-bearingformations-Saertu,PutaohuaandGaotai...

Synthesis of PMA/Eu_2O_3 porous-layered nanocomposite by in situ polymerization and its morphology

The PMA/Eu2O3 porous and layered nanocomposite was prepared by in situ polymerization and characterized by means of X-ray diffraction （XRD）, transmission electron microscopy （TEM）, scanning electron microscope （SEM）, and inflared ray （IR）. Microscopic investigation of the nanocomposite was carded out by atomic force microscopy （AFM）. The results showed that the shape of the composite was layered and porous. Eu2O3 was grafted when methyl acrylate （MA） polymerized; thus Eu2O3 particles appeared on both sides of the chains of polymeric methyl acrylate （PMA）.

Cinnamate-functionalized hyperbranched polymer as liquid crystal photo-alignment layer

In this work, 4-methoxylcinnamoyl chloride was reacted with a commercial hyperbranched polymer （Boltom-TM H30） to prepare a hyperbranched photosensitive polymer （H30-Ci）. The polymer was characterized by UV absorption spectrum and 1H- NMR spectrum. After processed by Linearly Polarized Polymerization （LPP） method, the spin-coated films of H30-Ci were used as photo-alignment layers to assemble liquid crystal （LC） cells containing nematic liquid crystal （5CB）. The observation by polarized microscope showed that the H30-Ci blended with a linear polymer （BP-AN-Ci） photo-alignment layers could align LC molecules in a very uniform way.

Entropy dominated behaviors of confined polymer-nanoparticle composites

Stretched polymers will lose their possible configurations if they are mixed with nanoparticles or touch a hard wall, which leads to a strong depletion attraction responsible for the enrichment of nanoparticles near substrates. Moreover, it is found that there exists a sacrifice mechanism in confined pure polymer samples or polymer-nanoparticle mixtures, that part of the polymers, in order to reach a minimum free energy for the total system, are adsorbed on hard walls even though they lose their conformation. The current study provides a simple yet effective approach for the design of thin polymer composites.

A New 2D Double-layer Network Constructed from a 2D Single Layer

Two Zn（II） coordination polymers, namely [Zn2（bpy）（aobtc）（H2O）2]·2H2O（1） and [Zn2（bpy）（aobtc）（H2O）]·4H2O（2）（bpy = 4,4＇-bipyridine, H4 aobtc = 3,3＇,5,5＇-azoxybenzenetetracarboxylic acid） have been hydrothermally synthesized through tuning the p H value of the reaction system（1, C（26）H（22）N（4）O（13）Zn2, Mr = 729.21; 2, C（26）H（24）N4O（14）Zn2, Mr = 747.23）, and their structures have been determined by single-crystal X-ray diffraction analyses. Compound 2 has been further characterized by infrared spectra（IR）, elemental analyses, thermal analyses and powder X-ray diffraction（PXRD） analyses. Additionally, the photoluminescence of 2 is also discussed. The structure demonstrates that the crystal of 2 belongs to the triclinic system, space group P1 with a = 8.41494（18）, b = 9.59838（19）, c = 17.6477（3） ？, α = 91.5098（16）, β = 98.1439（17）, γ = 90.4323（17）°, V = 1410.44（5） ^3, Z = 2, ρcalc = 1.759 g/cm^3, μ = 2.819 mm-1, F（000） = 760.0, R = 0.0311 and w R = 0.0839（I 〉 2σ（I））. Compound 1 shows a two-dimensional monolayer while compound 2 displays a novel 2D double-layered network constructed from monolayer motifs, which is similar to the single layer in 1. Further, each bilayer motif in 2 is interdigitated by two others in a parallel fashion to yield an unusual 2D → 3D interdigitated framework.

Recent progress on non-thermal plasma technology for high barrier layer fabrication

This review describes the application of non-thermal plasma（NTP） technology for high barrier layer fabrication in packaging area.NTP technology is considered to be the most prospective approaches for the barrier layer fabrication over the past decades due to unpollution,high speed,low-costing.The applications of NTP technology have achieved numerous exciting results in high barrier packaging area.Now it seemly demands a detailed review to summarize the past works and direct the future developments.This review focuses on the different NTP resources applied in the high barrier area,the role of plasma surface modification on packaging film surface properties,and the deposition of different barrier coatings based on NTP technology.In particular,this review emphasizes the cutting-edge technologies of NTP on interlayer deposition with organic,inorganic for multilayer barriers fabrication.The future prospects of NTP technology in high barrier film areas are also described.

Inverted organic solar cells with solvothermal synthesized vanadium-doped TiO2 thin films as efficient electron transport layer

We investigated the effects of using different thicknesses of pure and vanadium-doped thin films of TiO2 as the electron transport layer in the inverted configuration of organic photovoltaic cells based on poly（3-hexylthiophene） P3HT：[6-6] phenyl-（6） butyric acid methyl ester（PCBM）. 1% vanadium-doped TiO2nanoparticles were synthesized via the solvothermal method. Crystalline structure, morphology, and optical properties of pure and vanadium-doped TiO2 thin films were studied by different techniques such as x-ray diffraction, scanning electron microscopy, transmittance electron microscopy, and UV–visible transmission spectrum. The doctor blade method which is compatible with roll-2-roll printing was used for deposition of pure and vanadium-doped TiO2 thin films with thicknesses of 30 nm and 60 nm. The final results revealed that the best thickness of TiO2 thin films for our fabricated cells was 30 nm. The cell with vanadium-doped TiO2 thin film showed slightly higher power conversion efficiency and great Jsc of 10.7 mA/cm^2 compared with its pure counterpart. In the cells using 60 nm pure and vanadium-doped TiO2 layers, the cell using the doped layer showed much higher efficiency. It is remarkable that the external quantum efficiency of vanadium-doped TiO2 thin film was better in all wavelengths.

Tethering of Homo and Block Glycopolymer Chains onto Montmorillonite Surface by Atom Transfer Radical Polymerization

Well-defined homo glycopolymer/montmorillonite (MMT) nanocomposite (gly1) was prepared successfully by the “grafting from” technique from the modified surface of MMT via surface initiated atom transfer radical polymerization (SI-ATRP) of 3-O-methacryloyl-1,2:5,6-di-O-isopropylidene-α-D-glucofuranose (gly) in the presence of Cu(I)Br/ bi- pyridyl at 90?C in xylene. Well-defined diblock copolymers (gly2, gly3, gly4 and gly5) were also synthesized via the same technique by using comonomers of methylmethacrylate (MMA) or styrene (St) with glycomonomer (gly) using the same catalytic system. The formed nanocomposites showed both intercalated and exfoliated structures, as judged by XRD and TEM measurements. Further analyses were performed on such nanocomposites to confirm their formation such as TGA and DSC. The structures of the attached polymers to MMT were characterized by 1H NMR.

界面聚合法聚酰胺分离层形成过程的模拟研究进展

近年来通过界面聚合(IP)法制备的聚酰胺(PA)薄层复合(TFC)膜广泛应用于纳滤、反渗透等水处理领域.采用IP法制备的PA分离层的形成机理及其动力学研究对TFC膜材料的设计和调控具有关键作用.本文从历史发展和聚合方法两个维度综述了PA分离层形成过程的模拟研究,具体涉及全原子分子动力学(MD)、粗粒化分子动力学(CGMD)和耗散粒子动力学(DPD)等3种方法.其中,全原子MD模拟采用链交联、单体交联及分级交联等3类方法,以距离准则为成键依据,构建了PA的聚合过程;CGMD方法减少了体系的自由度,得到的构型更加合理;DPD引入了反应概率,得以在更大的时空尺度中研究IP扩散与反应的竞争关系.重点关注IP反应的构建,总结了各模拟方法的特点、发展及其在IP法形成PA分离层中机理解读和性能预测方面的应用.

中间层构建及其反渗透复合膜性能的探讨

自制了聚氯乙烯(PVC)超滤基膜,通过多元胺(二乙烯三胺-DETA和哌嗪-PIP)和多元酸(衣康酸-IA、马来酸酐-MAH和柠檬酸-CA)反应形成了基膜表面中间层,采用间苯二胺(MPD)和均苯三甲酰氯(TMC)界面聚合(IP)制备了反渗透(RO)复合膜,讨论了多元胺/多元酸种类(DETA/CA,DETA/MAH,DETA/IA,PIP/IA)、反应次数等对中间层性能和RO膜性能的影响.结果表明,当50℃时,利用3 mol/L二乙烯三胺和0.5 mol/L衣康酸在基膜表面反应4次的中间层所制备的RO复合膜,在2.0 MPa压力下对质量浓度1800 mg/L的氯化钠水溶液脱盐率为97.58%,其水通量为34.8 L/(m^(2)·h·MPa),与空白对照RO膜相比水通量提升41.3%,因此,这种中间层构建的方法为高通量RO复合膜的制备提供了理论依据.

Layered coordination polymer with two-dimensional covalent bismuth-organic networks:Semiconductor and lithium ion storage

Single crystals of a bismuth-based coordination polymer(CP)with carboxyl-thiol ligands,[Bi(C_(8)H_(2)O_(4)S_(2))(C2H8N)]n(Bi-DSBDC-DMA,DMBDC=2,5-disulfur-1,4-dicarboxylate,DMA=dimethylamine),have been successfully synthesized.X-ray diffraction analysis reveals that Bi-DSBDC-DMA possesses a layered structure,with two-dimensional(2D)Bi-DSBDC networks alternating with layers composed of dimethylamine ions.This material demonstrates semiconducting properties,featuring an optical bandgap of 2.2 eV and an electrical conductivity of 2×10^(-8) S/cm.Furthermore,electrodes based on this material exhibit a capacity of 250 mAh/g after 200 cycles for lithium-ion storage.