［Objective］This study investigated the influence of different soft segment types（PPG， PCL，PTMG）on the impact resistance of polyurea，aiming to provide a theoretical basis for designinghigh-performance protective coatings and their engineering applications.［Methods］ Three spraypolyureas with different soft segment structures were synthesized via the prepolymer method. Theirchemical structures，thermal properties，dynamic mechanical behavior，energy dissipation capacity，and impact resistance were systematically characterized using Fourier transform infrared spectroscopy（FT-IR）， differential scanning calorimetry（DSC）， cyclic tensile testing，and drop-weight impact experiments.［Results］The soft segment structure significantly affected the microphase separation andmechanical properties of spray polyurea. PTMG-based spray polyurea exhibited the most pronouncedmicrophase separation，along with the highest tensile strength（28 MPa） and fracture energy（1 078. 55 kJ/m²）. However，its tendency toward brittle fracture in thick coatings（2 mm） could exacerbate substrate damage. In contrast，PCL-based spray polyurea achieved an optimal balance between strength，modulus and toughness. Under thick coating conditions，it effectively absorbed impact energy through large deformation，demonstrating superior impact protection performance. PPG-based spray polyurea was the most flexible（with the lowest T_g）. Its protective effectiveness relied on sufficiently thick coatings（≥1. 5 mm）to facilitate energy dissipation. All spray polyureas tested showed significant strain rate sensitivity，with both modulus and strength increasing with higher loading rates.［Conclusion］The impact resistance of spray polyurea was determined collectively by the chemical structure of the soft segment（which governed the microphase separation behavior and intrinsic toughness）and the coating thickness（which dictated the volume of energy absorption）. Owing to its superior overall properties，PCL-based spray polyurea represented the optimal choice for thick coatingsunder extreme impact conditions（e. g.，explosions and projectile impacts）. PPG-based spray polyureawas more suitable for vibration damping and shock absorption applications，while PTMG-based spraypolyurea was better adapted for use in thin coatings or scenarios requiring high strength under moderate（non-extreme）impact.

［Objective］As the traditional anti-corrosion coating which direct doping of corrosioninhibitor is easy to trigger the problems of early release，coating structure damage and attenuation of protective effect，this paper constructs a self-repairing epoxy composite coating system based on pH responsive intelligent nanocontainers.［Methods］ Silicone nanocontainers（HPMO） with hollow mesoporous structure were designed and synthesised by the hard template method，combined with vacuum impregnation technique to load the corrosion inhibitor 2-mercaptobenzothiazole（MBT）， the smart anticorrosion system of HPMO@MBT was then constructed. The epoxy composite coatings wereprepared by regulating the addition amount of HPMO@MBT nanocontainers. The structural characteristics of the nanocontainer，the release behaviour of the corrosion inhibitor and the anticorrosion performance of composite coating were systematically investigated.［Results］The results showed that HPMO possessed a high specific surface area and uniform mesoporous distribution，and the MBT loading reached 17. 5%，which could be released quickly in response to the acidic environment.Electrochemical impedance spectroscopy（EIS）and scratch tests revealed that the composite coatingexhibited a significantly slowed low-frequency impedance decay rate during 15 days of immersion in a
3. 5%NaCl solution，when HPMO@MBT mass fraction is 1%. Over a specific time scale，it demonstrated an evolutionary shift from decline to recovery or stabilization，reflecting the synergisticcontribution of the coating's barrier function and interfacial inhibition effect. Scratch immersion resultsrevealed enriched distributions of N and S elements within the damaged area，indicating directed migration of the corrosion inhibitor under corrosion-induced conditions and its participation in interfacial protection. Excessive HPMO@MBT addition（>1%）may weaken coating performance due to nanocontainer aggregation and increased local porosity.［Conclusion］The above results indicate that by reasonably designing the structure of the nanocontainer and the HPMO@MBT addition amount，the stable storage and environmentally responsive release of corrosion inhibitors can be achieved under thepremise of ensuring the structural integrity of the coating，the anti-corrosion stability of the coating under the condition of local damage is enhanced.

［Objective］The objective of this study is to prepare a fast-drying，medium-resistant， and tough polyamide-based aqueous epoxy curing agent.［Methods］ A polyamide intermediate containing three terminal amine groups（JXA-4D） was first synthesized in one step via a Michael addition reaction using maleic anhydride（MA）and 4，4'-diaminodicyclohexylmethane（H₁₂MDA）as raw materials. Subsequently，the polyamide waterborne epoxy curing agent（MK-165）was synthesized from JXA-4D，a composite polyamine，epoxy resin（NPEL-128）， and polyethylene glycol diglycidyl ether（PEGDGE）. The thermal properties of MK-165 were then analyzed.［Results］The FT-IR results showed that JXA-4D and MK were successfully synthesized. The prepared JXA-4D exhibited a short-chain high-branched structure with three terminal amine groups. Its low viscosity and high amine valuesignificantly improved reactivity and crosslinking density. MK-165，synthesized from JXA-4D curedNPEL-128 had a stable synthesis process and showed good universality to a variety of epoxy primers.The two-component waterborne epoxy coating prepared with MK-165 exhibited excellent mechanicalproperties，with the cured film achieving both high hardness（3H）and good flexibility（1 mm bend test）. The curing speed was fast，the working time was 4 h at room temperature，while maintaining curability in low-temperature environments. Furthermore，the coating demonstrates long-lasting media resistance，including 720 hours of salt spray resistance and 960 hours of water resistance.［Conclusion］ A polyamide curing agent was successfully prepared based on the Michael addition method. Whenapplied in two-component coatings，the hardness and curing speed of the coatings were effectively maintained. These findings provided a useful theoretical basis and research foundation for the subsequent development of novel polyamide curing agents.

［Objective］To modify moisture-curable polyurethane with silane coupling agents toimprove its thermal resistance for the conservation of cultural relics in humid environments.［Methods］A partially silane-terminated silicone-modified moisture-curable polyurethane was synthesized using polyether polyols（polyethylene glycol and polytetramethylene ether glycol）and aliphatic isocyanates（isophorone diisocyanate） as precursors，with trimethoxy（3-（phenylamino）propyl）silane as the secondary aminosilane coupling agent. The polyurethane films were characterized through chroma meter， UV-Vis spectrophotometry，Fourier-transform infrared spectroscopy（FT-IR）， thermogravimetric analysis（TGA），and thermal-oxidative aging tests to evaluate their appearance，hydrogen bonding degree， and thermal stability.［Results］The results showed that the silicone coupling agent-modified moisture-curable polyurethane films exhibited a visible light transmittance of 85%-89% with a color difference（ΔE）of <0. 4. Increasing the hard segment/soft segment mass ratio enhanced microphase separation， while increasing the dosage of the secondary aminosilane coupling agent reduced it. The activationenergies calculated by the Flynn-Wall-Ozawa（FWO）and Kissinger-Akahira-Sunose（KAS）methods increased from 77. 33-99. 71 kJ/mol to 104. 02-127. 39 kJ/mol before and after silicone modification， showing an increase of 27. 8%-34. 5%. The thermal degradation mechanisms were consistent withdiffusion models（D₁，D₂，and D₃）and the reaction order model（F_n）. The color difference upon heating was reduced.［Conclusion］ The synthesized silicone coupling agent-modified polyurethane is colorless and transparent，exhibits excellent thermal stability，and shows promising potential forapplication in the conservation of fragile organic cultural relics excavated from humid environments.

［Objective］ To further improve the etch resistance and thermal stability of printed circuit board（PCB） solder resist inks.［Methods］ Four alkaline-soluble fluorene-based epoxyacrylates modified with different anhydrides（maleic anhydride（MA）phthalic anhydride（PA），methyl nadic anhydride（MNA），andtetrahydrophthalicanhydride（THPA））were synthesized. The structuresof the four epoxy acrylates were characterized using Fourier transform infrared（FT-IR）spectroscopyand proton nuclear magnetic resonance（¹H NMR） and their basic properties were systematicallyinvestigated. Among them，the THPA-modified alkali-soluble fluorene-based epoxy acrylate（FATH） demonstrated excellent photosensitivity，thermal resistance，and mechanical properties. Therefore，the influence of FATH addition amount on the etch resistance and thermal stability of the solder resist inkwas further explored.［Results］Increasing the mass ratio of FATH could effectively improve both etchresistance and thermal stability of the solder resist ink. When the mass ratio of FATH to commercial o-cresol novolac epoxy resin（R5185）reached 3∶2，the onset thermal decomposition temperature of the solder resist ink increased from 365. 33 ℃（without FATH）to 372.67℃，while the side etching of developed lines decreased from 44. 2 μm（without FATH） to 37.4μm，achieving a development resolution of 50 μm.［Conclusion］This work will effectively promote the development of novel PCBsolder resist inks with high etch resistance and thermal stability.

［Objective］ To address the erosion damage and poor interfacial adhesion betweenprotective coatings and concrete substrates for underwater concrete structures，a wet-curable concrete protective coating containing catechol groups was prepared based on the biomimetic mussel adhesionprinciple.［Methods］Epoxy resin（EP）was modified with nano-zirconium dioxide particles（ZrO₂）. Dopamine hydrochloride（DA）was then crosslinked with aminopropyl polydimethylsiloxane（PDMAS）. Subsequently，a catechol-containing epoxy coating（ZrO₂/EP/D-PDMAS）was prepared via sequential interpenetrating polymer network（IPN）technology. The molecular structure and microstructure of thecoating were characterized by Fourier transform infrared spectroscopy（FT-IR）and scanning electron microscopy（SEM）. The effect of DA content on the comprehensive performance of the coating was investigated through tests of adhesion strength，corrosion resistance，and mechanical properties.
［Results］The results showed that the ZrO₂/EP/D-PDMAS coating exhibited optimal comprehensiveperformance at a DA content of 4wt% . It achieved an adhesion strength of 4. 59 MPa on concretesurfaces in underwater environments，representing a 117. 54% increase compared with the ZrO₂/EP coating. Moreover，relative to the pure EP coating，the corrosion current density of the ZrO2/EP/D-PDMAS coating reduced from 4. 914×10^-7 A/cm² to 4. 393×10^-8 A/cm²，and the corrosion potential positively shifted from -0. 709 V to -0. 597 V.［Conclusion］ The ZrO2/EP/D-PDMAS coatingeffectively resolved the insufficient interfacial bonding strength of underwater concrete coatings throughthe biomimetic adhesion effect of catechol groups. With its simple synthesis process，low raw material cost，excellent interfacial adhesion and corrosion resistance，this coating significantly enhanced the protection of concrete substrates.

［Objective］To address issues such as sand adhesion，metal penetration，and cleaningdifficulties that commonly occur at the interface between sand molds with external chills and castings.［Methods］A suspension agent was prepared by composite modification of lithium based bentoniteusing a two-step method of "intercalation grafting" with bauxite white corundum as the composite refractory aggregate. The coating was formulated by combining a composite binder consisting of phenolic resin and polyvinyl butyral（PVB） with industrial ethanol as the solvent. Orthogonal experiments were carried out to systematically investigate the effects of the composite-modified suspending agent content，refractory aggregate gradation，and binder ratio on the coating properties. Theoptimal formulation was determined through range analysis and weight normalization.［Results］The results showed that the optimized coating achieved a 24 h suspension rate of 95%，a gas evolution value of 12. 6 mL/g，a brushing performance grade of Class Ⅰ，and excellent wear resistance. Production validation on 30-ton machine tool bed castings indicated that the chill surface coated with thedeveloped formulation exhibited a surface roughness（Ra）of 12.5μm，a sand adhesion area of less than 2%，and no obvious pores（Φ>2 mm）or metal penetration. Additionally，the surface cleaning time was significantly shortened，and the recovery rate of chills was greatly improved.［Conclusion］This study provided an effective solution for optimizing coatings used in the external chill chilling process.

［Objective］ To address the difficulty of removing oil stains caused by the surface roughness of existing matte coatings for large aircraft.［Methods］ High-solid，low-viscosity hydroxylated polyester was synthesized by using furandicarboxylic acid（FDCA）derived from lignin to replace 1，4-cyclohexanedicarboxylic acid（CHDA）. The synthesized polyester resin was characterized by gel permeation chromatography（GPC）， Fourier-transform infrared spectroscopy（FT-IR）， and differential scanning calorimetry（DSC）to determine its relative molecular weight，chemical structure， and glass transition temperature，respectively. Its viscosity was measured using a rotational viscometer.The resin was formulated as component A of a two-component aircraft skin coating and combined withan isocyanate curing agent to prepare test panels. The heat resistance，resistance to artificial contamination，impact resistance，resistance to aviation fuels，resistance to artificial UV aging，and pencil hardness of the coating were tested.［Results］The cleaning efficiency of the low-gloss coatingreached 98. 2%，and all other performance parameters met the requirements of aviation coatings.［Conclusion］ The resin prepared with FDCA exhibits superior stain resistance compared to thepolyester resin prepared with CHDA.

［Objective］The green and environmentally friendly fully bio-based flame-retardantimpregnating solution for lyocell fabrics with ultra-efficient flame-retardant and excellent wearingperformance were prepared in the water solvent.［Methods］Phytic acid（PA）and copper gluconate（CG）were used to synthesize the flame-retardant impregnating solution（PC），then the flame-retardant lyocell fabrics（Lyocell/PC） were prepared through impregnation，rolling and baking processes. Characterization was performed using X-ray photoelectron spectroscopy（XPS）and scanning electron microscopy energy dispersive spectroscopy（SEM-EDS）.［Results］The PC was successfully preparedand applied to the surface on the lyocell fabrics. When the loading of PC reached 3. 6%，the limiting oxygen index（LOI）of Lyocell/PC increased to 29. 3%. Besides，it passed the vertical burning test（VBT）， and the heat release was significantly suppressed. The flame-retardant mechanism indicatsthat PC could decompose in advance to form dense carbon layers to protect lyocell fabrics duringcombustion. Meanwhile，it produced a large amount of non-combustible gases to dilute the concentration of combustible gases in the air，achieving a good flame-retardant effect. In addition，compared with pure lyocell fabrics，Lyocell/PC fabrics had no change in strength，moisture regain，air permeability，and hand feel.［Conclusion］The fully bio-based flame-retardant impregnating solutionnot only could be prepared using a green and environmentally friendly method，but it could also endow the lyocell fabrics with excellent fire safety and wearing performance.

［Objective］To address the long-term corrosion protection requirements for Q235 steelstructures in coastal environments with high salinity and humidity，a comparative study was conducted on the protective performance evolution of two coating systems—bare steel with a primer/intermediate/topcoat system and galvanized steel with another primer/intermediate/topcoat system—under accelerated neutral salt spray and ultraviolet aging conditions. The differences in corrosion resistance behavior and failure mechanisms between the two systems were systematically evaluated，providing an experimental basis for the rational selection of coating systems for steelstructures in coastal regions.［Methods］Through surface analysis，chemical structure changes，and electrochemical tests，the failure mechanism of the two coating systems under accelerated corrosion testconditions were elucidated.［Results］The results showed that the bare steel coating system exhibited superior corrosion resistance and stability compared to the galvanized steel coating system under bothneutral salt spray and UV aging tests. The failure of the bare steel coating system was mainly attributedto chloride ion penetration and photo-oxidation，whereas the failure of the galvanized steel coatingsystem was closely associated with insufficient interfacial stability and localized reactions between thegalvanized layer and penetrating species from the coating.［Conclusion］Considering the performance and failure mechanism of the two coating systems，the bare steel with primer/intermediate/topcoatsystem was recommended for coastal and other highly corrosive environments to improve protectiveperformance，reduce maintenance costs，and ensure the long-term stable operation of coastal infrastructure. 

［Objective］In response to the increasingly prominent corrosion issue at door hemming positions，this study focuses on the frequent filiform corrosion failures of zinc-aluminum-magnesiumcoated steel sheets at the hemming of door inner panels. It aims to systematically evaluate the corrosionresistance of the coated steel sheets，clarify the induction mechanism of filiform corrosion，and propose efficient prevention and control technical schemes.［Methods］ Systematic corrosion resistance assessment of zinc-aluminum-magnesium coated steel sheets was conducted from three core dimensions：uniform corrosion，sharp-edge corrosion，and crevice corrosion. Combined with actual service conditions，the structural characteristics of the hemming，material surface state，and environmental factors were analyzed emphatically to explore the formation path of filiform corrosion in depth.［Results］ There exists an electrochemical potential difference in the zinc-aluminum-magnesium coating. Combined with the structural defect of insufficiently filled hemming adhesive at the door hemming and poor quality of the pretreatment film，acetic acid medium remains in the hemming cavity. These three factors act synergistically in a high-temperature and high-humidity environment，ultimately triggering filiform corrosion. The adoption of combined protective measures such as full-cavity adhesive sealing，improving the quality of the pretreatment film，removing residual acetic acid，and spraying anti-corrosion wax can significantly reduce the incidence of this corrosion problem.［Conclusion］The corrosion resistance of zinc-aluminum-magnesium coated steel sheets should bedefined through multi-dimensional comprehensive evaluation. The filiform corrosion at the hemming ofdoor inner panels is the result of the combined action of electrochemical potential difference，hemming adhesive filling defects，pretreatment film quality，medium residue，and environmental factors. The application of targeted combined protective technologies can effectively improve the corrosion reliabilityand service life of this key position.

［Objective/Significance］ Poly（vinylidene fluoride）（PVDF），a high-performance fluoropolymer，is witnessing increasing demand across diverse applications，particularly in specialized coatings and new energy sectors. However，the polymerization of vinylidene fluoride（VDF）presentssignificant challenges due to its inherent heterogeneous nature and highly exothermic reaction，which lead to a strong coupling between the polymerization kinetics and multiphase mass transfer. This complex interplay creates substantial hurdles for industrial-scale reactor design and scale-up.［Analysis/Discussion/Progress］ This review summarizes the advancements in VDF polymerization processes（including emulsion，suspension，solution，and supercritical polymerization），reactor design（covering batch reactor，tubular reactor and other new types of reactors），and associated modeling studies.［Conclusion/Prospect］ Our aim is to provide valuable insights for the efficient，safe，and industrial-scale production of high-performance PVDF，while also promoting the continuous upgrade of related engineering technologies.