Abstract:Supported catalysts are widely used in important fields such as petrochemicals and fine chemicals, among which the support function is extremely crucial. Porous spherical alumina carriers account for the largest share in industrial carriers due to their numerous crystal forms, excellent pore structure, and stable chemical properties. However, their performance is closely related to the corresponding pore structure and its hydrothermal stability. This work mainly summarizes the recent research progress on the pore structure and the corresponding hydrothermal stability control strategies of spherical alumina both domestically and internationally. On the one hand, it focuses on the regulation rules of carrier pore structure from three aspects: Al2O3 precursor, oil ammonia column forming process, and post-treatment. On the other hand, it discusses the regulation mechanism and enhancement methods of alumina pore structure hydrothermal stability, such as surface hydroxyl passivation and γ-Al2O3 content. It may provide suggestions for the regulation of pore structure and hydrothermal stability of high-value spherical alumina industrial carriers in China, with the aim of breaking through relevant key technologies and building an independent intellectual property system.

Abstract:Liquid metal is a kind of functional materials with both electrical conductivity and fluidity, and has gained widespread attention for its excellent conductivity and deformation capabilities. Fiber materials, as the common flexible substrate, have shown broad application potential in many fields due to their excellent stretchability, breathability, and weavability. In order to solve the problem of poor flexibility of electronic components and difficulty in meeting wearable and intelligent requirements, starting from the matrix and conductive materials, combining with the advantages of stretchable deformation and flexibility of fiber materials and the high conductivity and room temperature fluidity of liquid metal (LM), LM-based fiber composite materials were prepared, which have been widely used in fields such as human motion monitoring and energy storage. Firstly, the control strategies for the LM in terms of chemical stability, electrical and thermal properties and the methods of combining with fiber materials are introduced, including coating, injection and electrospinning methods. Then, the research progress of LM-based fiber composites in sensing, electromagnetic shielding, energy harvesting and storage are emphasized. Finally, suggestions are proposed for the improving of its performance and addressing the remaining issues in current research, and future development directions are anticipated.

Abstract:With the strengthening of environmental awareness and regulations, waterborne polyurethane (WPU), as an environmentally friendly water-based resin, has been widely applied and studied. Currently, one of the main issues with WPU products in the adhesive field is the solid content. Excessive water content in the product leads to problems in drying, production efficiency, and adhesive performance. This paper provides a review of research methods for preparing high solids low viscosity WPU in recent years, including optimizing the phase inversion process, increasing space utilization, reducing hydration layer, combining internal and external emulsification methods, and hyperbranched structures. The review summarizes the impact of different factors on the phase inversion process and explains how to optimize this process through changes in techniques and equipment. Suggestions are presented for addressing factors that restrict solid content, such as limitations in emulsion particle packing density, hydration layer thickness, and viscosity. By increasing the solid content, the slow drying and insufficient bonding capacity issues in waterborne polyurethane adhesives can be resolved. This review has practical significance for optimizing the preparation and application of WPU adhesives.

Abstract:Biomass materials are materials derived from living organisms with renewable and degradable characteristics, and their structures are rich in a variety of active groups, which can produce strong interactions with electrode active materials such as hydrogen bonding, ion-dipole and chemical bonding. Traditional oil-soluble binders have poor adhesion ability, volatile solvents and a certain degree of toxicity, which is contrary to the concept of green development and environmental protection. In order to achieve carbon peak and carbon neutrality, it is of great significance to introduce biomass into battery binders to replace oil-soluble traditional binders. This paper reviews the characteristics of biomass binders, the mechanism of interaction with active materials, focuses on and summarises the application of biomass binders in lithium-ion batteries and sodium-ion batteries, and looks ahead to the direction of the development of biomass binders in the field of electrochemistry. Future research should still focus on the modification of natural biomass to combine good adhesion, dispersion, electrical conductivity and self-healing properties, in order to better utilise the structural and functional properties of biomass materials for the preparation of binders for lithium-ion batteries and sodium-ion batteries.

Abstract:Adsorptive atmospheric water harvesting technology, which makes use of hygroscopic materials to adsorb water vapour from the air, desorb it through solar-driven desorption, and collect it through condensation to produce fresh liquid water, has been acknowledged as a promising technology for decentralized water supply in arid areas. In order to realise the practical application of this technology in daily life, industrial and agricultural production, etc. as soon as possible, researchers have carried out a lot of explorations and practices and made some breakthroughs. Based on a brief introduction of the technical process of adsorption, desorption and condensation collection in adsorption atmospheric water harvesting, this paper focuses on the desorption stage, summarises in detail the hygroscopic and desorption mechanisms of moisture-absorbing materials and seeks to elucidate the optimisation strategies to improve the desorption capacity and condensation effect based on the material structure and collector design. Finally, the paper provides an overview of the challenges faced by solar-driven atmospheric water harvesting (SAWH) from the aspects of both basic research and practical application, as well as the outlook of the future development of the technology.

Abstract:Advancements in nanotechnology have led to the emergence of magnetic polymer microspheres as a promising nanomaterial with magnetic responsiveness in the petroleum industry. This article provides a comprehensive overview of the preparation techniques and current research status of nano-magnetic polymer microspheres, highlighting their applications in oil-water separation, efficient desulfurization, catalytic modification, and intelligent oil recovery mechanisms and achievements. Future directions are proposed to address the current development status of nano-magnetic polymer microspheres, including enhancing magnetic properties, improving stability, surface modification, and studying the underlying mechanisms. This review aims to provide valuable insights and references for research and applications in related fields.

Abstract:AZIBs manganese oxide cathode materials were prepared from electrolytic manganese anode mud (EMAM) by roasting activation method, and the effects of different roasting temperatures (300, 425 and 575 ℃) on the structure, morphology and electrochemical properties of the manganese oxide cathode materials under nitrogen atmosphere were investigated by XRD, TGA, SEM, and electrochemical performance tests. The results showed that the nitrogen atmosphere roasting improved the diffractivity and crystallinity of the manganese oxide cathode materials, and the materials showed the morphology of flakes and particles, the agglomeration phenomenon was reduced, and the voids were increased. The structure of the manganese oxide cathode materials was gradually transformed from α-MnO2 to Mn2O3 and Mn3O4 with the increase of the roasting temperature. Through the roasting, the specific capacity of the manganese oxide cathode materials in first discharge, the multiplicity performance and the first discharge specific capacity, multiplicity performance and cycling performance of the manganese oxide cathode material are improved, and the material has a smaller Vaalborg coefficient and a faster diffusion rate of Zn2+. Among them, the manganese oxide cathode material (300-EMAM) prepared at a roasting temperature of 300 ℃ showed better electrochemical performance, with an initial discharge specific capacity of 232 mA·h/g at a multiplication rate of 5 C. The reversible specific capacity of the 300-EMAM was maintained at 190.0 mA·h/g after 100 cycles; the 300-EMAM electrode had a lower contact resistance ( 33.6 Ω) and charge transfer resistance (816.3 Ω).

Abstract:The amphiphilic carboxylic acid derivatives, 5-[(4-(diphenylamino)phenyl)]thiophen-2-carboxylic acid and its potassium salts (TTC-H and TTC-K), were synthesized through a Suzuki coupling reaction involving 5-bromothiophen-2-carboxylic acid and [(4-(diphenylamino)phenyl)]boric acid. The structures of the two compounds were characterized by 1HNMR and 13CNMR. The UV-Vis absorption spectroscopy was used to verify the photophysical properties of TTC-H and TTC-K, while fluorescence emission spectroscopy systematically discussed their aggregated states. Density-functional theory calculations and solvation colorimetric effects confirmed the charge transfer properties within the molecules of TTC-H and TTC-K. Their crystal structures were resolved and analyzed by Hirshfeld surface analysis, and the results showed that there were weak interaction forces between TTC-H molecules, such as C···H (31.6%, accounting for the percentage of the total interaction force, similarly hereinafter), H···H (44.6%) and O···H (14.6%). Both TTC-H and TTC-K possessed the property of aggregation-induced emission (AIE). The aqueous solution of TTC-K was proved effective in revealing the tertiary structure of latent fingerprints through chemical impregnation and atomization methods with a good stability of aging. And even at low concentrations (5×10-5 mol/L), the TTC-K aqueous solution reagent enabled rapid identification of latent fingerprints (≤5 s) by chemical impregnation method. And both old fingerprints (≤14 d) and fingerprints soaked in water (≤7 d) have good imaging effects.

Abstract:Monodisperse polystyrene(PS)@SiO2 core-shell nanometer microspheres are prepared by emulsion polymerization combined with an improved Sto ?ber method, PS@SiO2 particles are then dispersed in the precursor of poly(ethylene glycol) phenyl ether acrylate (PEGPEA), forming a fast photopolymerization capture regular array after forming a non-dense particle array, and preparing a mechanically discolored photonic crystal film. The structure, optical properties and photochromic properties of photonic crystal thin films were characterized and tested by SEM and optical fiber spectrometer. The influence of the volume fraction and particle size of PS@SiO2 particles on the structure color of photonic crystal thin films was investigated, and the mechanism of photochromic effect of PS@SiO2 particles on the structure color of photonic crystal thin films was predicted. The results show that the heat treatment by ultraviolet light changes the microstructure order of PS@SiO2 particles and causes them to form the structure of opal photonic crystal. The structure color of photonic crystals gradually changes from red to blue with the increase of PS@SiO2 particle volume fraction or the decrease of particle diameter. Photonic crystal thin film has structural color reflectivity> 60%, tensile strain 70%, sensitivity 2.16 nm/%, response speed 1.9 nm/ms, reflection wavelength tuning range(Δλ)=152 nm. After 100 stretch/release cycles and 3 d recovery at 25 ℃, the structure color of the photonic crystal film remained unchanged. The unique core-shell structure of PS@SiO2 nano-microspheres has elasticity and stretchability. PS improves the refractive index difference between the nano-microspheres and the elastomer matrix, can improve the reflectivity, and can make the structure color of the photonic crystal thin film brighter. During the stretching process, the colloidal particles can remain constant by following the position of the elongated lattice. The negligible rearrangement of the particles makes the color shift of the photonic crystal film completely reversible under strain, so the deformation is elastic and there is no residual strain.

Abstract:A superhydrophilic-underwater superoleophobic stainless steel mesh (SSM-PDA-SiO2) was prepared using a stepwise deposition and in-situ growth method for gravity-driven oil-water separation. Nano-sized silica (SiO2) was grown in situ on a polydopamine (PDA) modified stainless steel mesh to impart superhydrophilic-underwater superoleophobic properties. The chemical composition, morphology, and wettability of the modified stainless steel mesh were characterized using techniques such as FT-IR, XRD, TG, SEM, and contact angle measurement. The experimental results showed that the SSM-PDA-SiO2 obtained after eight hours of silica sol addition exhibited the highest underwater contact angle (159.6°) and the lowest rolling angle (5°), demonstrating superhydrophilic-underwater superoleophobic properties. The modified stainless steel mesh achieved an initial separation flux of 40165 Lm-2h-1 with a separation efficiency of 99.3%. Even after 50 separation cycles, it still maintained a flux of 17728 Lm-2h-1 and a separation efficiency of 98%, indicating good recyclability. Additionally, after 35 cycles of sandpaper abrasion, the modified stainless steel mesh retained a separation efficiency of over 98%, demonstrating good mechanical stability.

Abstract:In order to improve the photocatalytic degradation ability of TiO₂, TiO₂-g-C₃N₄-ZIF-67 catalysts were prepared by Co-doping g-C₃N₄, ZIF-67 with TiO₂ by sol-calcination method. The effects of g-C₃N₄, ZIF-67 on the morphology and structure of TiO₂ were investigated based on XRD, XPS, SEM, and UV-vis DRS characterization; and the photocatalytic activity of TiO₂and its composites was evaluated by the degradation rate of methyl orange. The results showed that the band gap of g-C₃N₄ doped TiO₂ could be reduced from 3.04 eV to 2.45 eV compared with that of undoped samples, and continued to be doped with ZIF-67, and the band gap was further reduced to 1.91 eV after doping, among which TiO₂-g-C₃N₄-ZIF-67-2 corresponding to a cobalt mass content of 21.50% had the highest activity and was able to degrade 79.92% of methyl orange in 40 min and 90 min. of methyl orange at 40 min and 89.50% of methyl orange at 90 min. The Co-doped samples had good cycling stability, and the TiO₂-g-C₃N₄-ZIF-67-2 catalyst had a degradation rate of 58.86% after three cycles.

Abstract:W/Si emulsifier (EMCD) with UV absorption was prepared by grafting Chalcone derivative (E)-3-(4-allyloxygen)phenyl-1-(4-methoxy-phenyl)propyl-2-alkene-1-ketone (Methoxy-Cha) and allyl polyether APEG-400 onto hydrogen-containing silicone oil chains. The chemical structure of the product was determined by NMR. EMCD can stabilize the emulsion with the best stability when the ratio of silicon to water ranges from 25:75 to 17.5:82.5, and the mass fraction of EMCD is about 2%. The maximum total efficiency was 5.237% when EMCD was combined with MBBT. Compared with KF-6017, EMCD can increase the SPF value of sunscreen lotion from 21.76 to 33.29, and the average UVA/UVB ratio from 0.433 to 0.587, enhancing the broad spectrum protection capability of sunscreen lotion.

Abstract:In this study, the ultrasonic-assisted ionic liquid extraction of Artemisiae argyi leaves flavonoids was optimized using single-factor tests and the response surface method, and its antioxidant and hypoglycemic activities were determined in vitro. The results showed that the optimal process parameters for the extraction of A. argyi leaf flavonoids as follow: 8 g/L 1-Butyl-3-methylimidazolium Bromide ([C4mim]Br) as extraction solvent, ultrasonic time of 68 min, and material-liquid ratio of 1:30 g/mL. Under the optimized conditions, the yield of A. argyi leaf flavonoids was 14.36%. In vitro antioxidant assay showed that A. argyi leaf flavonoids have good scavenging abilities against 1,1-diphenyl-2-trinitrophenylhydrazine radicals (DPPH ?), 2,2-diazo-di (3-ethylbenzothiazole-6-sulfonic acid) diamine salts (ABTS+), and ?OH, with a corresponding half inhibitory concentration (IC50) of 0.15, 0.12 and 0.6 mg/mL, respectively. In vitro hypoglycemic assay showed that A. argyi leaf flavonoids have the inhibitory effect on α-amylase and α-glucosidase, with the IC50 value of 0.59 and 0.37 mg/mL, respectively. The flavonoids of A. argyi leaf had good antioxidant properties and hypoglycemic activity.

Abstract:In order to study the optimal extraction process, physicochemical properties and antioxidant and hypoglycemic activities of Conioselinum vaginatium,ultrasound-assisted extraction of Conioselinum vaginatium was carried out using 1-ethyl-3methylimidazole bromide (ionic liquid), and the optimal extraction process of polysaccharides was optimized by single-factor and response surface experiments. The crude polysaccharide (CV-1) of Conioselinum vaginatium after removing impurities such as protein, pigment and small molecules, was subjected to preliminary physicochemical property studies.The in vitro antioxidant capacity of CV-1 was evaluated by ABTS radical scavenging and hydroxyl radical scavenging, and the in vitro hypoglycemic capacity of CV-1 was evaluated by α-glucosidase and α-amylase inhibition. The results showed that the optimal extraction process of CV-1 was as follows: sonication time of 115 min, enzyme digestion time of 90 min, sonication temperature of 55 ℃, ionic liquid mass concentration of 4 g/L, material-liquid ratio of 1:50, and mass fraction of pectinase of 0.6 %, and the amount of CV-1 extracted under these conditions was (125.278 ± 0.707 mg/g).The weighted relative molecular mass of CV-1 was 17.57 CV-1 has a gravimetric relative molecular mass of 17.57 KDa, and is mainly composed of five sugar residues (mannose, glucose, rhamnose, arabinose, fucose, molar percentages of 5.94 %, 6.8 %, 28.03 %, 18.4 %, 40.83 %), is a triple-helical conformational α-constituent glycoside coexisting in an amorphous and crystalline structure, and does not contain proteins and glucuronic acid, and has an excellent thermal stability, and has an excellent thermal stability.Scanning electron microscopy revealed that CV-1 has a lamellar structure with locally flat surfaces.The half-scavenging concentrations (IC50) for ABTS radical and hydroxyl radical were 1.122 mg/mL and 1.373 mg/mL, respectively, and the IC50 for α-glucosidase and α-amylase were 14.799 mg/mL and 15.739 mg/mL.
Keywords:Conioselinum vaginatium polysaccharide; chemicalcomposition; physico chemical; antio-xidant activity; hypoglycemic activity

Abstract:A series of ZnO samples with different morphologies were synthesized by controlled preparation methods and processes,and employed as catalysts for the synthesis of diethyl oxalate (DEO) from dimethyl oxalate (DMO) and ethanol by transesterification route. The structure-activitySrelationships of this transesterification reaction over ZnO were systematically discussed with the help of XRD, N₂Sphysisorption, XPS, SEM and CO₂-TPD techniques. It was found that the catalytic activity of ZnO catalysts in the transesterification of DMO with ethanol is closely related to the ZnO morphologies. Among them, the flower-like ZnO-f is found to be the most active catalyst, and the DMO conversion over ZnO-f can reach 99.8 % with the selectivity to DEO of 75.8 % under the optimal conditions. The DMO conversion and DEO selectivity decrease from 99.1% and 68.2% to 93.9 % and 24.7 % after four cycles, respectively. This catalystSdeactivation can be ascribed to the presence of Zn(OH)₂ phase. Kinetic studies showed that the transesterification of DMO with ethanol over ZnO-f catalystSfollowsSfirst-orderSreaction with activation energy of 35.7 kJ/mol, and the abundant medium and strong basic sites over ZnO-f is responsible for its excellent catalytic activity in the transesterification reaction of the DMO reaction with ethanol.

Abstract:Palygorskite (PAL) was treated with HCl to prepare pickling palygorskite (PA), and modified PAL (PCS, PDO, PKH) were prepared by organic modification of PA (chitosan, cationic surfactant dioctadecyl dimethyl ammonium chloride, silane coupling agent KH550). Finally, modified palygorskite/sappanwood hybrid pigments (short for hybrid pigment, the same as full text) PAS, PCSS, PDOS, PKHS were prepared by PA, PCS, PDO, PKH loaded with sappanwoood dye extract. Through FTIR, XRD, TEM, BET, TG and color characterization, the effects of different modification methods on the powder properties, stability and biosafety of the prepared hybrid pigments were investigated. The results showed that organic modification and sappanwoood dye extract loading do not change the crystal structure and fiber morphology of PAL. The hybrid pigments significantly improved the thermal stability, acid-base stability and covering power of sappanwoood dye extract. Hybrid pigment (PCSS) prepared by chitosan modified PAL showed better comprehensive properties: thermal stability (ΔE<6 on exposure to 120 ℃ for 6 h), the best acid-base stability (ΔE<4 on soaking in pH=5~9 solution for 24 h), the lowest water-alcohol dissolution rate (2.13 mg/g in water and 1.02 mg/g in ethanol), high biosafety (non-irritant to vascular membrane).

Abstract:The main ingredient of the study is the leaves of the lingonberry. The liquid-liquid extraction technique was employed to analyze the primary constituents of Vietnamese kumquat leaves and to formulate pH-sensitive liposomes containing Vietnamese kumquat leaf flavonoids. The study also investigated their in vitro release at various pH levels and their inhibitory effect on HepG2 cells. Eighteen fractions were obtained using ultrasound-assisted extraction and macroporous resin purification. The optimal components were analyzed using the activity tracking method for liquid-liquid analysis. pH-sensitive liposomes were prepared using the ethanol injection method, which was combined with carboxymethyl chitosan surface modification. The liposomes were characterized using Fourier transform infrared spectroscopy, particle size analysis, polydispersity index measurement, zeta potential determination, and the dialysis method to analyze their in vitro release capability. The inhibitory effect of the liposomes on HepG2 cells was determined through analysis of cell proliferation, migration, and the cell cycle. The results showed that the macroporous resin effectively increased the purity and antioxidant capacity of the flavonoids. The concentration of purified flavonoids reached 899.44 mg/g. HPLC-MS analysis identified nine components, including epicatechin-3-O-cinnamate, catechin, dihydromyricetin, glycyrrhizic chalcone A, quercetin-3β-D-glucoside, kaempferol-3-O-L-rhamnoside, isorhamnetin-3-6-gallic acid glucoside, kaempferol 3-(6-gallic acid lactose), and quercetin 3-(2-gallic acid ellagic acid glucoside). The encapsulation efficiency of the liposomes prepared with this flavonoid is 81.77±3.02%, with a particle size of 408.30±2.23 nm and a uniform particle size distribution. When the concentration of carboxymethyl chitosan is 0.4%, the solution exhibits the highest stability, as indicated by the highest absolute value of x-potential. In vitro release experiments have shown its pH sensitivity, with a cumulative release of 98.03±3.18% in 48 hours at a release medium pH of 4.0. Additionally, it conforms to the Weibull model. Cell experiments further demonstrate that compared to liposomes without carboxymethyl chitosan encapsulation, liposomes with carboxymethyl chitosan encapsulation exhibit pH sensitivity, enhance the inhibitory ability of HepG2 cells, and block the HepG2 cells from staying in the S and G2 phases.

Abstract:Using polyvinyl alcohol ( PVA ) and soluble starch as film-forming matrix, glycerol as plasticizer, and sweet corncob polysaccharide ( SCP ) as raw material, silver nanoparticles ( AgNPs ) were added to enhance the comprehensive packaging performance and prepare composite film materials. The tensile strength was used as an index to optimize the single factor and response surface experiments, and the film materials were characterized by SEM and Fourier transform infrared spectroscopy. The results showed that the tensile strength of PVA-AgNPs film was ( 14.08 ± 0.58 ) MPa, and it had degradable ability. Compared with PVA film, the water resistance and barrier ability of PVA-AgNPs film were enhanced. In addition, the use of PVA-AgNPs film as a packaging material at 4 °C storage conditions reduced the weight loss rate, spoilage rate, soluble solids and VC content loss of strawberries, and effectively slowed down the softening and decay of strawberries. The amount of silver migration in the fruit after storage was 0.00188 mg / kg, which was much lower than the national standard.

Abstract:A organic-inorganic composite membrane sealing agent was synthesized using modified nano SiO2 as rigid particles, acrylamide, 2-acrylamido-2-methylpropane sulfonic acid, styrene, and vinyl acetate as polymerization monomers, OP-10 and sodium dodecyl sulfonate as emulsifying agents, and ammonium persulfate and sodium bisulfite as initiators. The morphology and structure of the product were characterized using FTIR, TGA, DLS, and SEM. The effects of the sealing agent on the rheological properties, filtration properties, and sealing performance of water-based drilling fluids were studied. The results indicate that the composite film-forming sealing agent is spherical and maintains a nanoscale distribution. At a temperature of 340 ℃, the mass loss is approximately 14% of the total mass. After aging at 120 ℃ for 16 hours, the viscosity performance increases compared to before aging. When the amount of sealing agent added is 3% (based on the total mass of the system, the same below), the API filtration loss is 10mL. When the dosage of sealing agent is greater than 2%, the filtration loss of the sand bed is 0mL. When the dosage is 4%, the high-temperature and high-pressure filtration loss is reduced from 104 mL to 29mL, and the sealing rate is 90.7%.

Abstract:Three typical polyester-based particles, polylactic acid (PLA), polyglycolide (PGA) and polybutylene adipate-terephthalate (PBAT), were used as representatives to investigate the degradation law and hydrolysis mechanism of polyester-based particles as temporary plugging agents and evaluate their blocking performance. The results showed that the larger the mass concentration of hydrochloric acid and sodium hydroxide, the higher the temperature, the shorter the complete degradation time, and at the same mass concentration, the degradation in sodium hydroxide solution was faster, and the complete degradation time of PLA, PGA and PBAT in 100 g/L sodium hydroxide solution at 90 ℃ was 15h, 12h and 18d, respectively. The hydrolysis mechanism of polyester particle plugging agent was elucidated with the help of FTIR, XRD and SEM: at the early stage of degradation, the ester group began to hydrolyze, holes appeared on the surface of the particles, and the volume of the particles was slightly reduced; as the degradation proceeded, the hydrolysis preferentially took place in the amorphous zone, the crystallinity increased, the carbonyl index decreased, the hydroxyl index increased, and the holes on the surface of the particles increased and the volume was further reduced; at the late stage of degradation, the hydrolysis of crystalline zone started, the crystallinity decreased, and a large number of polymer molecular chains were broken until the complete degradation. The blocking experiment shows that the larger the mass concentration of the injected polyester particles plugging agent is, the denser the blocking layer is, the stronger the pressure-bearing capacity is, and the pressure-bearing capacity is PLA, PGA, PBAT in descending order.

Abstract:Using acrylic acid (AA), butyl acrylate (BA), methyl methacrylate (MMA), hydroxypropyl acrylate (HPA), hydroxyethyl methacrylate (HEMA) as the base monomers, ethylene glycol dimethacrylate (EGDMA) and glycidyl methacrylate (GMA) as the cross-linking monomers, self-crosslinking core-shell acrylic emulsions were prepared by two-step emulsion polymerization, and it was further used as a water-based ink linker to prepare water-based ink. The significance factors of the core-shell properties affecting the water resistance and adhesion of the inks were investigated by interactive orthogonal tests, and the optimum formulation for preparing self-crosslinking core-shell acrylic emulsion was determined by exploring the significance factors. The structure and properties of the self-crosslinked core-shell acrylic emulsions and the prepared latex films were characterized and tested by using TEM, FTIR, TG, DSC, water absorption, water contact angle, and universal materials testing machine, etc. The effects of the mass fraction of GMA in the shell layer monomer on the emulsion particle size, stability, and the adhesion and water resistance of the prepared inks were investigated. The results show that the AA mass ratio (core-shell acrylic acid ratio) between the core-layer mixed monomer and the shell-layer mixed monomer has a significant effect on ink adhesion, and the MMA mass ratio (core-shell softness/hardness ratio) between the core-layer mixed monomer and the shell-layer mixed monomer has a significant effect on the water resistance of the ink. The optimal formulation of the self-crosslinking core-shell acrylic emulsion is as follows: the mass ratio of the core layer mixed monomer to the shell layer mixed monomer (core-to-shell mass ratio) 2:3, the core-to-shell softness ratio 3:0.75, the core-to-shell acrylic ratio 0.5:2.5, and the amount of internal crosslinking monomer EGDMA is 0.75 g. When the mass fraction of GMA in the shell layer monomer was 1.5%, the average particle size of the self-crosslinked core-shell acrylic emulsion was 112.2 nm, the PDI was 0.108, the maximum thermal decomposition rate was at 409 ℃, and the glass transition temperatures (Tg) of the core and shell layers were 28.5 and 51.7 ℃, respectively. The dispersion stability of the emulsion was optimal, and the water absorption rate of the prepared latex film was 34.55%, and the adhesion of the prepared ink was 99%, and the water resistance was 50 times.

Abstract:Traditional light curing or heat curing adhesives are difficult to meet the needs of 3D printing molding. Thermal dual curing strategy is a hot research direction in the field of explosive 3D printing molding. In this paper, under the photothermal dual-curing strategy, a new type of acrylic ester hydroxyl-terminated polyether adhesive with the characteristics of rapid curing and complete curing in a short time was designed and synthesized. The obtained target adhesive has lower viscosity and better mechanical properties at low temperature. The optimum curing process parameters and the optimal material ratio as well as the elasticity of the photothermal double curing system were determined. The mechanical properties, thermal stability and tensile properties of the polymer were investigated. The experimental results showed that the target MAPTHF based adhesive system could be cured quickly within 5 s under ultraviolet light and completely cured within 3 h under heating. The tensile strength and elongation of the elastomer film formed by MAPTHF based photothermal dual curing were 3.15 Mpa and 350%. Compared with elastomer film formed by photo curing and thermal curing alone, it has better mechanical properties. Both thermodynamic properties and viscosity of the target adhesive meet the need of the 3D printing molding process and have been verified by 3D printing experiments. This kind of photothermal dual–curing adhesive solves the problem of slow curing speed and incomplete curing of traditional photo curing. It not only provide support for promoting the application of 3D printing in explosive formula but also lay solid foundations for solving the difficulty of precise rapid prototyping and accurate performance control of traditional explosive column molding process.

Abstract:A viscosity-reducing polycarboxylate superplasticizer (VR-PCE-TR) with narrow molecular distribution was synthesized by thermally initiated reversible addition-fragmentation chain transfer (RAFT) polymerization in continuous tubular reactor, using isoprenyl-PE-PPG and maleic anhydride as main raw materials. The molecular structure of VR-PCE-TR was determined by 1H NMR、FTIR and GPC. Then, the surface tension, uniformity, concrete experiment and mechanical strength have been measured to compare working performance and rheological properties with various viscosity-reducing polycarboxylate superplasticizers, which are synthesized by conventional free radical polymerization. The results show that when the mass fraction of polycarboxylate superplasticizer is 10%, VR-PCE-TR has a lower surface tension (30.65 mN/m); When polycarboxylate superplasticizers content are 8 mg/g, the cement slurry with VR-PCE-TR has a higher adsorption capacity (2.803 mg/g); When the dosage of polycarboxylate superplasticizers are 0.13%, the cement slurry with VR-PCE-TR has better dispersion and dispersion retention performance; When the dosage of polycarboxylate superplasticizers are 0.4%, the cement slurry with VR-PCE-TR has a lower yield stress (1.3 Pa) and lower plastic viscosity (0.26 Pa·s).Furthermore, the synthesis of VR-PCE-TR by thermally initiated RAFT polymerization in continuous tubular reactor without degassing process, are able to maintain the polymerization speed and control, achieving narrower molecular distribution (PDI=1.19), better viscosity reduction effect and application performance.

Abstract:To cope with the corrosion problem of metal equipment caused by sudden temperature changes and abundant precipitation in the Northeast region of China and to improve the dispersibility and corrosion protection ability of graphene oxide (GO) doped in waterborne acrylic resin (AP), GO was modified using hexamethylene diisocyanate (Tri-HDI), p-phenylenediamine, polyethylene pyrrolidone (PVP) and 3-aminopropyltriethoxysilane (APTES) to improve the dispersibility, layer spacing and strength of GO, and obtain reinforced dispersion graphene oxide (RDGO). Finally, RDGO and AP were combined using wet transfer method to prepare waterborne anti-corrosion coating RDGO/AP. The physical properties and corrosion resistance of RDGO/AP coating were investigated using FTIR, Raman, XRD, SEM characterization, TGA testing, as well as electrochemical and corrosion experiments. The results showed that GO introduced new C—N groups and RDGO exhibited a two-dimensional crystal structure. The interlayer spacing was increased from 0.0761 nm to 0.1045 nm, and thus the aggregation phenomenon of GO was avoided. The starting temperature for weight loss of RDGO was 259.16 ℃ and RDGO had good thermal stability. Compared with AP coating, the water contact angle (98°) of RDGO/AP coating increased by 4°, the hardness (4H) increased by 2H, and the adhesion (level 1) increased by 2 levels. After soaking in a 3.5% NaCl solution for 14 days, the corrosion voltage of RDGO/AP coating increased by 0.479 V and the corrosion current density decreased by 1.172×10-5 A/cm2 compared with AP coating. The protection efficiency of RDGO/AP coating was up to 99.90%. The reason why RDGO/AP had good corrosion resistance was that after binding with AP, carbonyl groups on the surface of RDGO were prone to grafting with the hydrogen atoms in AP, improving the dispersibility of RDGO in the acrylic resin, strengthening the interfacial adhesion, increasing the toughness and shear strength of the coating, and elevating the adhesion between RDGO and the film-forming substrate, thereby enhancing the anti-corrosion effect of the coating.

Abstract:Organic urea compounds were prepared directly using CO2 and organic amines as raw materials without any dehydrating agent participating in the reaction process, the optimal reaction conditions were obtained by optimizing factors such as temperature, pressure, concentration, time, solvent, type and dosage of catalysts and additives. The reaction conditions were as follows: at a temperature of 190℃, carbon dioxide pressure of 4.5 MPa, inorganic base Cs2CO3 as catalyst, Bu4NBr as additive, and N-methyl pyrrolidone (NMP) as solvent, reaction concentration of 6.67mmol/mL, after 6 hours of reaction, 15 symmetric organic urea compounds with different alkyl or aryl substitutions were prepared in good yields, with yields ranging from 55% to 80%. Their structures were characterized using 1H NMR and 13C NMR, and possible reaction mechanisms were analyzed. This method has the characteristics of convenience, efficiency, environmental friendliness, and atomic economy.