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In response to the difficulties students face in understanding abstract structures and complex reactions in organic chemistry teaching, this study explores the combination of virtual reality (VR) technology, specifically the chemistry metaverse, with organic chemistry courses. This approach allows students to learn about the molecular structure, spatial conformation, and reaction mechanisms of organic compounds through interactive learning. The integration of VR technology not only improves the quality of organic chemistry teaching, but also enhances students' interest in learning, as well as their hands-on and innovative abilities. Additionally, this research analyzes the challenges and innovations in applying VR technology to organic chemistry teaching. By addressing the gap in the use of VR technology in organic chemistry teaching and research in domestic universities, this study demonstrates its significant potential. [ABSTRACT FROM AUTHOR]

Triazolopyrimidine compounds containing carboxyl and thioether groups were synthesized using 3-amino5-mercapto-1,2,4-triazole, benzyl bromide, and diethyl ethoxymethylenemalonate (EMME) as starting materials. The synthesis involved nucleophilic substitution, cyclization, and hydrolysis reactions. The resulting products were characterized and analyzed for their structures. The experiment included techniques such as heating reflux, TLC (thinlayer chromatography) detection, filtration, and recrystallization, which aimed to enhance students' skills in multi-step organic compound synthesis and spectral analysis. Triazolopyrimidine compounds are widely found in natural products and pharmaceuticals. The synthesis of these compounds not only provides insight into societal demands but also integrates cutting-edge research and theoretical knowledge taught in the classroom, thereby improving the quality of experimental teaching and achieving excellent educational outcomes. [ABSTRACT FROM AUTHOR]

A two-step synthetic experiment to produce paracetamol from 4-hydroxyacetophenone was designed for undergraduate organic chemistry courses. The experiment begins with the condensation of 4-hydroxyacetophenone with hydroxylamine to form 4-hydroxyacetophenone oxime. This oxime then undergoes a Beckmann rearrangement catalyzed by cyanuric chloride to yield paracetamol. The experiment incorporates several essential organic laboratory techniques, such as reflux, extraction, drying, filtration, rotary evaporation, thin-layer chromatography, and column chromatography, providing students with comprehensive training in organic synthesis. By synthesizing a compound of significant medical and economic value, the experiment demonstrates practical applications of organic synthesis, thereby enhancing student interest in organic chemistry. Additionally, the use of a small molecule organic catalyst for the Beckmann rearrangement deepens students’ understanding of the principles of organic catalysis and the mechanism of the Beckmann rearrangement. [ABSTRACT FROM AUTHOR]

This article presents a comprehensive organic chemistry experiment in which salicylaldehyde, phenylboronic acid, and aromatic amines are employed as the substrates. The selective synthesis of diarylmethyl aniline and triarylmethane could be achieved through the control of substituents. The structure of the product is characterized by ¹H NMR and 13C NMR. This experiment combines theoretical knowledge to inspire students to think about mechanisms, helps them broaden their knowledge horizons, and establishes the concept of "green chemistry" and environmental awareness. [ABSTRACT FROM AUTHOR]

In order to improve the teaching quality of Organic Chemistry courses in normal universities, this study analyzes the problems in the construction of this course based on the principles of “student-centered, outcomeoriented, and continuous improvement”. The analysis is conducted from both the perspectives of student learning and teacher instruction. Moreover, targeted solutions are proposed, and the implementation of the “128” strategy for course construction is described. As a result, a distinctive and highly effective teaching system for Organic Chemistry courses has been established, leading to significant achievements in curriculum development. [ABSTRACT FROM AUTHOR]

Chlorinated polyethylene rubber (CM)/nitrile rubber (NBR) blend vulcanizates were prepared by mechanical blending method with CM and NBR as main raw materials, the cross-linking density of CM phase in CM/NBR blend vulcanizate and the stress-strain relationship of CM/NBR blend vulcaizate were characterized by regulating the dose of vulcanization system of CM phase in CM/NBR blend combined with the means of equilibrium swelling method, testing mechanical properties and theoretical calculation, and the influence of the change of cross-linking density of CM phase on matching degree of the modulus of two phase in CM/NBR blend vulcanizate and mechanical properties of CM/NBR blend vulcanizate were studied. The results showed that the change of the modulus of CM/NBR blend vulcanizate caused by the increase in cross-linking density of CM phase was greater than that of its own; with the increase of modulus, the influence of the change of cross-linking density of CM phase on the modulus of CM/NBR blend vulcanizate increased; by comparing the stress-strain relationship of CM phase and NBR phase in CM/NBR blend vulcanizate and the change of mechanical properties of CM/NBR blend vulcanizate, it was proved that the decrease of the cross-linking density of CM phase was a process of the gradual matching of the modulus of the two phase; compared with the error of the measured stress-strain relation, that of the stress-strain relationship predicted by fitting model was relatively smaller, which indicated that fitting model had certain applicability.

The ash content of rubber was determined by thermogravimetric analysis (TGA) and the effects of sample amount, sample representativeness, heating rate, combustion temperature and combustion atmosphere on the test results were studied and the repeatability and reproducibility of the method were determined. The results showed that the optimal conditions of TGA were sample mass between 10 mg and 20 mg, heating rate of 20 ℃/min or 30 ℃/min, combustion temperature for raw rubber and compounded rubber (or vulcanized rubber) of 550 ℃ and 650 ℃, respectively. The repeatability and reproducibility of TGA were all good. When ash mass fraction of 4 types of different rubbers were from 0.29% to 5.12%, the repeatability within laboratory was from 0.110% to 0.303%, and the reproducibility between laboratories was from 0.283% to 0.676%.

With thermoplastic polyurethane (TPU) limit spring extruder head as the research object, the relevant material parameters of the constitutive equation of raw TPU were obtained by the rheological property test. Numerical simulation of the flow process of TPU in the extrusion runner was carried out based on the software Polyflow, and in the meanwhile, a second-order regression model of standard deviation of velocity (Sd) at the exit of the forming section was established by response surface method, and the influence law of extrusion runner structure on the melt flow uniformity of TPU was explored. The results showed that after optimization the structure parameters of extrusion runner were as follows: the length of the forming section of 165 mm, the expansion angle of 25°, and the number of diverter shuttles of 6. After optimization the predicted value of Sd at the exit of the forming section of extrusion runner was 0.531 m/s and was only 0.188% different from the actual value of Sd(0.532 m/s), which indicated that the model was more accurate, and the model could be used for the prediction and optimization of the structure parameters of extrusion runner.

Screw pump stator material was prepared with hydrogenated nitrile rubber as raw material, and the chemical aging damage of the screw pump stator material in different crude oil environment temperatures was studied by simulating real oil production environment and using a microscope and attenuated total reflection Fourier transform infrared spectroscopy. In addition, the chemical damage mechanism of the screw pump stator material in crude oil environment was explored. The results showed that the temperature of the crude oil and aging time had an important influence on the chemical aging damage of the screw pump stator material, and when the aging time was same, the mass change rate of the screw pump stator material increased with the increase in crude oil temperature, while at the same aging temperature, the mass change rate of the screw pump stator material increased with the prolongation of aging time and the increase rate of of mass change rate tended to slow down. The chemical damage mechanism of the screw pump stator material in the crude oil environment of 25 ℃ was mainly the fracture of molecular chains and the oxidation cross-linking reaction of carbon chains; in the crude oil environment of 60 ℃, the chemical damage mechanism included primarily the fracture of molecular chains, the oxidation cross-linking of carbon chains and the oxidation cross-linking reaction of nitrile groups; while in the crude oil environment of 100 ℃, the chemical damage mechanism consisted mainly of the fracture of molecular chains, the oxidation cross-linking reaction of carbon chains, the oxidation cross-linking reaction of nitrile groups and the cross-linking reaction between nitrile groups resulted from high temperature.

Genetic algorithm (GA) and particle swarm optimization (PSO) were used to optimize the back propagation（BP） neural network to establish the prediction model of Mooney viscosity of ethylene-propylene-diene monomer (EPDM) compound, and the error of the prediction results was compared and analyzed. The results showed that the predicted va-lues of the BP neural network model optimized by the two algorithms all maintained a high degree of fit and correlation with the measured values. Compared with the single BP neural network, the accuracy of the GA-BP neural network prediction model increased by 58.9% and the accuracy of the PSO-BP model increased by 3.57%, which indicated that the prediction accuracy of the prediction model optimized by the two algorithms, especially the BP neural network prediction model optimized by GA, improved significantly Mooney viscosity of EPDM compound.

Isobutylene polymerization was studied with the rare-earth metal scandium cationic complexes as catalysts and molecular weight and its distribution, and glass transition temperature of polyisobutylene were investigated by screening the catalyst system, adjusting the ratio of monomer to catalyst and regulating the reaction temperature and time. The results showed that the constrained-geometry-configuration scandium dialkyl catalyst which had relatively smaller steric hindrance had the highest catalytic activity for isobutylene polymerization among 5 kinds of rare-earth metal scandium cationic catalysts. The higher mole ratio of monomer isobutylene to catalyst was, the higher number-average relative molecular weight the resulting polymer had. The lower reaction temperature was, the higher numbe-average relative molecular weight of the polymer was, however, when the reaction temperature was below -60 ℃, the number-average relative molecular weight of the polymer decreased significantly. The reaction time had little effect on the change of the number-average relative molecular weight of the polymer. In addition, the polymerization reaction temperature and time had no significant effect on the glass transition temperature of polyisobutylene.

"Molecular weight and its distribution, molecular structure composition, curing characteristics, Mooney viscosity, physical and mechanical property, thermal-oxidative aging resistance, low temperature performance and catalyst residual amount of similar brand hydrogenated nitrile rubber (HNBR) products from Zannan SciTech Co Ltd and Zeon Corporation of Japan were mainly compared. The results showed that molecular weight and its distribution, molecular structure composition, Mooney viscosity of raw rubber, scorch time of compound, thermal-oxidative aging resistance and low temperature performance of HNBR ZN 35156 from Zannan SciTech Co Ltd were generally equivalent to those of Zetpol 2010 L from Zeon Corporation, and compared with Zetpol 2010 L, ZN 35156 raw rubber had somewhat lower saturation degree, and ZN 35156 compound had a little faster curing rate and slightly poorer processing performance, while ZN 35156 vulcanizate had slightly superior physical and mechanical properties such as hardness and tensile strength; molecular weight and its distribution, molecular structure composition, Mooney viscosity of raw rubber, scorch time of compound and thermal-oxidative aging resistance of HNBR ZN 35158 from Zannan SciTech Co Ltd were basically similar to those of Zetpol 2010 from Zeon Corporation, and compared with Zetpol 2010, bound acrylonitrile content of ZN 35158 raw rubber was greater, ZN 35158 compound had a little faster curing rate and slightly poorer processing performance, and ZN 35158 vulcanizate had slightly poorer low temperature performance, while ZN 35158 vulcanizate had slightly superior physical and mechanical properties such as hardness and tensile strength; hydrogenation catalysts of Zannan SciTech Co Ltd and Zeon Corporation were ruthenium-based catalyst and palladium-based catalysts, respectively, and catalyst residual amounts in HNBR products of Zannan SciTech Co Ltd were re-latively less. "

The volatile content in nitrile rubber was measured by halogen moisture meter and compared with the results obtained by the hot-roll method. The influence of different measurement conditions on the measured results of the halogen moisture meter was investigated. The results showed that using the halogen moisture meter, the volatile content in nitrile rubber raw rubber could be measured by both the preset drying time method and preset mass loss method. Under suitable conditions such as sample mass of 3 g, drying temperature of 110 ℃, preset heating time of 8 min, or preset mass loss of 1/140 mg/s, the measured results were consistent with the hot-roll method. This method reduced measure time, was easy to operate, and could be used to guide quickly actual production.

Based on the piezoresistive effect of nano conductive rubber, conductive silicone rubber composite pressure sensor was prepared using the matrix material silicone rubber, nano superconductive carbon black, silk fiber fabric, interdigital electrode, buffer polymer material and encapsulation mold by processes such as internal mixing, open mixing, vulcanization and encapsulating, and the conductive silicone rubber composite material with the optimal piezoresistive characteristics was prepared by optimizing the content of conductive filler in the silicone rubber matrix. Finally, the application performance of encapsulated pressure sensor on bridge support model was explored. The results showed that when mass faction of nano superconductive carbon black ■ was 6.11%, the conductive silicone rubber composite material reached the penetration threshold point and had the best piezoresistive characteristics; the conductive sensing composite material obtained by implanting silk fiber fabric into conductive silicone rubber was then combined with the flexible interdigital single-layer electrode and encapsulated to generate the pressure sensor with increased range, sensitive detection, and enhanced toughness; the pressure sensor had a good linear relationship between the pressure signal and the electrical signal, and could achieve pressure detection within the range of 0 to 40 MPa. In addition, the measured value of the pressure sensor in the bridge support model test were highly consistent with the theoretical value.

Zinc oxide/melamine hypophosphate (MHS)/butyl tape premix (BTP) flame-retardant composites were prepared by mixing MHS, zinc oxide and BTP using mechanical blending method and the synergistic flame retardant effect between zinc oxide and MHS was investigated. The combustion performance and thermal stability of zinc oxide/MHS/BTP composites were studied by scanning electron microscope, limited oxygen index, cone calorimetry and thermogravimetric analysis, and the effect of zinc oxide on the adhesive performance of zinc oxide/MHS/BTP composites was studied by persistent adhesion and peel strength test. The results showed that the addition of zinc oxide could adjust the carbon formation and foaming process of the MHS/BTP composite and result in the generation of a complete gas chamber structure. The limited oxygen index of the composite increased from 28.5% to 33.0%, the vertical combustion grade of UL-94 increased from V-1 to V-0, the peak of heat release rate of the MHS/BTP flame-retardant composite could decrease by 66.7% at most, the total heat release decreased by 22.0%, the peak of smoke release rate decreased by 67.3% and the total smoke release decreased by 58.5%. The mass fraction of carbon residue of the MHS/BTP flame retardant composite increased from 25.58% to 40.41% and the maximum thermal decomposition temperature increased from 344.96 °C to 394.91 °C. The addition of zinc oxide would lead to a slight reduction of persistent adhesion and peel strength of the MHS/BTP flame retardant composite.

The application of neodymium based cis-1,4-polybutadiene rubber (Nd-BR) BR 9101 N in the formula of support compound of run-flat tire was studied, and compared with those of foreign same type product Nd-BR CB 24. The results showed that Nd-BR BR 9101 N could meet the requirements for incoming inspection of Nd-BR raw material, and the basic compounding performance could be met. When Nd-BR BR 9101 N was used in the formula of support compound of run-flat tire to replace Nd-BR CB 24 with the same amount, Mooney viscosity, scorch time and curing characteristics of the former compound, and physical and mechanical property of Nd-BR BR 9101 N vulcanizate before and after aging were basically the same to those of the latter, and the aging performance of the former improved, whereas the compression fatigue temperature rise and compression set all reduced compared with those of the latter. The high-speed durability of finished tire made from Nd-BR BR 9101 N was good and could meet the product design requirements and exceeded the national standard regulations, which were basically equivalent to those of the existing production tire, in addition, the strength performance and zero-pressure durability of finished tire made from Nd-BR BR 9101 N improved compared with those of the existing production tire.

Silica/solution-polymerized butadiene-styrene rubber (SSBR)/natural rubber (NR) compo-sites were prepared by mechanical mixing method with silane coupling agent, bis[3-(triethoxysilyl)propyl]tetrasulfide (Si 69) and 3-mercaptopropyl-ethyoxyl-di(tridecyl-pentamethoxy)-silane (Si 747), as modifier and the effect of types and addtion amounts of silane coupling agent on the microstructure, curing characteristics, processing performance, physical and mechanical performance, dynamic mechanical properties, tire performance, and the relationship between structure and performance of the composite. The results showed that compared with the composite just only modified by Si 69, the incorporation of Si 747 resulted in the scorch time and optimum curing time of the composite shorten signi-ficantly, and the curing rate improved gradually with the increase in the addition amount of Si 747; the synergistic modification of Si 69 and Si 747 made the physical and mechanical properties, tensile strength, resilience and modulus at 300% of the composite all reduced; when the addition amount of Si 747 increased, the apparent activation energy which was used to characterize the temperature dependence of storage modulus of the composite reduced gradually; the dispersion of silica in the composite improved significantly after the addition of Si 747; the loss factor (tan δ) of the composite modified by Si 747 alone at 0 ℃ increased significantly and tan δ at 60 ℃ decreased significantly; the rolling resistance of the tire improved gradually with the increase in the addition amount of Si 747.

Micro-nano rubber asphalt was prepared by high-temperature and high-speed shearing with micro-nano degraded rubber powder as raw material, and the micromorphology of micro-nano degraded rubber powder and miscible process of micro-nano rubber rubber and substrate asphalt were investigated by scanning electron microscopy, transmission electron microscopy and X-ray photoelectron spectrometer, and the road performance of micro-nano rubber asphalt mixture including water stability, temperature stability and cracking failure resistance were studied by the design of asphalt aggregate ratio. In addition, the application effect of micro-nano rubber asphalt mixture in practical road engineering was further evaluated. The results showed that mass fraction of sol in degraded rubber in which the size of dissociated carbon black was about 200 nm reached 65.7%, and the interaction of sulfur cross-linked bond between degraded rubber and asphalt appeared during the miscible process; the micro-nano rubber asphalt mixture showed excellent water stability, high- and low-temperature stability and cracking failure resistance; the key technical indexes of the upper layer and the lower layer in full-depth rubber asphalt pavement of test section of Jiuquan-Jiayuguan ring expressway prepared by using micro-nano rubber asphalt mixture in Gansu province all complied with the specifications and design requirements.

The combination method of numerical simulation and experimental verification was used to optimize the current evaluation method of tear strength of rubber unnicked angle test piece. Firstly, the tear energy at angle position of rubber test piece with different clamp distances was simulated by the simulation software, and then advanced video extensometer-digital image correlation analysis software was used to obtain the strain distribution cloud nephograms and the multi-location strain curves of the test piece with time. A new method was proposed to evaluate comprehensively the unnicked angle tear property by combining strain distribution cloud nephogram and corrected tear strength, and the method applicability was verified by the tear strength test of pure natural rubber and natural rubber/synthetic rubber blends. The results showed that the tensile degree of the non-effective test region and the tear energy at angle position were all different with the different clamp distances, when the other para-meters of the test piece were the same, which increased the volatility of the test results. Compared with the standard currently in effect, the variation coefficient of parallel test results could be reduced by using the corrected tear strength, and the test results was positively correlated with the carbon black dispersion in the vulcanizates.

"High trans-1,4-selective coordination chain transfer polymerization of butadiene was achieved through the catalysis of isopropoxyl neodymium/n-butyl magnesium catalyst system, the non-polar-polar diblock copolymer of trans-1,4-polybutadiene and polymethyl methacrylate （TPB-b-PMMA) was prepared after the addition of polar monomer methyl methacrylate（MMA）, and molecular weight and its distribution, microstructure, and surface morphology and micromorphology of the block copolymer thin film were characterized by gel permeation chromatography（GPC）, Fourier transform infrared spectroscopy, nuclear magnetic resonance spectroscopy, atomic force microscope, and transmission electron microscope. The results indicated that GPC curve of the obtained block copolymer showed single peak and the molecular weight distribution were relatively narrow （polydispersity index less than 2.5); the mole fraction of trans-1,4- unit of trans-1,4-polybutadiene segment in block copolymers was 95.8% and the mole fraction of MMA unit could be controlled within the range of 10.9% to 39.7%; the semicrystalline block copolymer thin film had a phase separation morphology with a cylindrical micro domain size of 25 nm. "

High- content rubber asphalt （HCRA) was prepared by using highly devulcanized rubber （DR), the effects of maleic anhydride （MAH) pre-grafted devulcanized rubber （DR) modification and direct blending modification of MAH and DR on the structure and properties of HCRA were comparatively studied by attenuated total reflection Fourier transform infrared spectrometer, gel permeation chromatography, dynamic shear rheometer and dynamic mechanical analyzer, and the modification mechanisms of two modification methods were explored. The results showed that during the pre-grafting of MAH onto DR, the free radical substitution reaction with active sites provided by olefin double bonds and allyl hydrocarbon atoms occurred, while when MAH and DR were directly blended with asphalt, there were two reactions: free radical substitution reaction and esterification, the latter being the main one. The sol components of MAH-modified HCRA were mainly composed of low and medium molecular weight components. The MAH improved significantly the high- and low-temperature rheological properties of HCRA. In addition, both the modification methods had an impact on the structure and properties of HCRA, and there were significant differences with the change of addition amount of MAH.

"With BE type rubber isolator as the research object, the hyperelastic and viscoelastic constitutive parameters of rubber materials were inverted through ABAQUS and ISIGHT joint simulation, based on the rated parameters of the isolator, and the prediction model of the rubber isolator was established using the inversion parameters. The results showed that the errors of the vertical, direction, and transverse static stiffness and three-dimensional dynamic stiffness were all less than 7%. When the prediction model was used to explore the effects of frequency, amplitude, and preload of rubber isolator on dynamic stiffness, the simulation results were basically consistent with the experimental results of similar rubber devices. When the prediction model was applied in the system level vibration simulation, the simulation results could match the vibration test results well. "

"First, a layer of inorganic self-assembled microencapsulated ammonium polyphosphate （APP) （SiO2@APP) was formed on the surface of APP using alkaline silica sol, and then grafting modified APP （KH 580-SiO2@APP) flame retardant was prepared via grafting modification of the silane coupling agent 3-mercaptopropyltriethoxysilane （KH 580) onto the surface of SiO2@APP by sol-gel method. Meanwhile, natural rubber （NR) composites were prepared by the application of KH 580-SiO2@APP to NR, and the effects of APP surface modification on the hydrophobicity, thermal stability, flame retardancy, and physical and mechanical properties of NR composite materials were studied. The results indicated that the surface modification of APP was successful. Compared with APP, the water contact angle of the resulting SiO2@APP increased by 205.7% and the thermal stability increased by about 25.7% after the modification with alkaline silica sol, and in the meantime, compared with APP/NR composite material, the tensile strength of SiO2@APP/NR composite increased by 43.7%, but the limited oxygen index （LOI) decreased. After the modification of SiO2@APP with the silane coupling agent KH 580, the water contact angle of the resul-ting KH 580-SiO2@APP increased by 9.1% and the increase in thermal stability was nearly 11.6%. In additon, the tensile strength of KH 580-SiO2@APP/NR composite was improved to 16.2 MPa, and the elongation at break increased by 539%, while the LOI decreased slightly to 24.3%. "

The reclamation law of natural rubber reinforced with silica （SNR) swollen by a small amount of soybean oil at different temperatures and in different time was studied, and the chemical composition and micromorphology of the reclaimed pro-ducts were determined. The results showed that within the temperature range of 160 and 240 ℃, the sol content of SNR increased continuously with the increasing temperature after swollen by soybean oil of 20 phr （mass), and when reclaimed at 220 ℃ for 15 min, the mass fraction of sol in the reclaimed product increased to 50.5%, and the mass fraction of sol in the reclaimed product was only 28.7% at 200 ℃, which indicated that 220 ℃ was an important turning point temperature in the reclamation process of SNR. The increase in oxygen content in the reclaimed product was due to the violent oxidation reaction of SNR during the reclamation process. In addition, as the degree of reclamation increased, the thickness of bound rubber of loose strata on the surface of silica decreased from 25 nm to 8 nm, indicating that thermal-oxidative reclamation could achieve a high degree of detachment between nano silica and its surface bound rubber.

The effects of common vulcanization （CV) system, semi-effective vulcanization （SEV) system, effective vulcanization （EV) system, and dicumene peroxide （DCP) vulcanization system on the mechanical properties and electromagnetic shielding effectiveness of Eucommia ulmoides gum （EUG) composites were studied. The results showed that the difference in vulcanization rates of CV system, SEV system and EV system was not significant, and the DCP vulcanization system had the lowest vulcanization rate and crosslinking degree, and exhibited the highest crystallinity degree. The elongation at break of EUG composites of the sulfur vulcanization systems were all higher than that of EUG composite of the peroxide vulcanization system, but the tensile strength was lower, and when DCP was used as the vulcanization agent, the tensile strength of EUG composite could increase by up to 10.6% compared with that of EUG composites of the sulfur vulcanization systems. EUG composites of sulfur vulcanization system exhibited good conductivity and the higher crosslinking density, which was conducive to the formation of conductive network, and the electromagnetic shielding effectiveness of EUG compo-sites of the EV system was 22% higher than that of EUG composites of the unvulcanized system.

A bio-based shape memory composite was prepared with chitosan as filler and deproteinized epoxidized natural rubber （ENR) as matrix, and the microstructure, mechanical properties, and shape memory performance of the shape memory composite materials were investigated by Fourier transform infrared spectroscopy, atomic force microscope, electronic universal testing machine, etc. The results showed that the addition of chitosan dispersed the ordered crystalline phases of ENR into smaller and more uniformly sized particles throughout the system. Due to the strengthening and toughening effect of chitosan, the abrasion resistance of the shape memory composite material was enhanced and its mechanical properties improved gradually. Furthermore, the addition of chitosan further improved the shape memory performance of ENR.

The effects of conventional vulcanization （CV) system, semi-effective vulcanization （SEV) system, effective vulcanization （EV) system, peroxide 1,3-bis（tert-butylperoxyisopropyl) benzene （BIBP)/triallyl isocyanurate （TAIC) vulcanization system, and phenolic resin SP 1045 vulcanization system on properties of poly（di-n-butyl itaconate-co-butadiene) rubber were studied. The results showed that the vulcanization rate of BIBP/TAIC vulcanization system was the fastest, while the vulcanization rate of SP 1045 vulcanization system was the slowest, and the vulcanization rate of CV system, SEV system, and EV system increased gradually in sequence. The crosslinking densities of the vulcanizates of the sulfur vulcanization systems in descending order were CV system, SEV system and EV system. Tensile strength of all the vulcanizates in descending order were SEV system, SP 1045 vulcanization system, CV system, EV system and BIBP/TAIC vulcanization system, in which elongation at break and tear strength of the vulcanizate of EV system were the largest, and the wear resistance of the vulcanizate of CV system was the best. The vulcanizate of BIBP/TAIC vulcanization system had the best thermal-oxydative aging property. Compared with the sulfur vulcanization systems, the glass transition temperatures of the vulcanizates of BIBP/TAIC and SP 1045 vulcanization systems shifted significantly towards to the high-temperature direction. The loss factor at 60 ℃ and rolling resistance of the vulcanizate of CV system were both the smallest. The effective damping temperature range of the vulcanizate of EV system was the widest.

Trial production and performance evaluation of finished tires were conducted with domestically produced double-end functional solutionpolymerized styrene-butadiene rubber SSBR 2060-N and single-end functional product ■from Zeon Corporation of Japan. The results showed that the finished tires produced from SSBR 2060-N conformed to the technical standards in terms of external dimensions, and the wet-skid resistance and rolling resistance met the double B-class tire specified by the tire labeling regulations EU 2020/740, jointly enacted by the European Parliament and the Council of the European Union. The strength performance, high-speed performance, and durability of the tires were comparable to those of the finished tire prepared with ■ and met the requirements of national standards.

Chlorinated polyethylene （CPE) flame retardant composites were prepared with CPE as the matrix material and sepiolite as flame retardant, and the effects of the addition amount of sepiolite on cu-ring characteristics, physical and mechanical properties, and flame retardance were studied. The results showed that with the increase in the addition amount of sepiolite, tensile strength, tear strength, modulus at 100%, modulus at 300%, and Shore A hardness of the composites increased significantly; the addition of sepiolite improved limiting oxygen index of the CPE flame retardant composites, reduced the maximum heat release rate and total heat release during combustion of the composites, prolonged the ignition time of the composites, reduced the absolute content of carbon monoxide and carbon dioxode, and decreased the smoke emission.

Silica was co-modified by silane coupling agent γ-aminopropyl triethoxysilane （APTES) and lauric acid （LA), the co-modified silica/solution-polymerized styrene-butadiene rubber （SSBR) composite was prepared, and the effects of co-modified silica by APTES and LA on curing characteristics, mechanical properties, wet skid resistance, and rolling resistance of SSBR composites were studied. The results showed that the mass loss of silica between 30 ℃ and 200 ℃ decreased by 54%, and the agglomeration was significantly improved after the co-modification. The optimum curing time of co-modified silica/SSBR composite was 20.45 min, tensile strength reached 18.8 MPa, and loss factors at 0 ℃ and 60 ℃ were 0.678 8 and 0.100 3, respectively.

Ethylene-butadiene-（5-ethylidene-2-norbornene) terpolymer （EBT)/nitrile rubber （NBR) blends were prepared by blending method, and the effects of different blending ratios on curing characteristics, physical and mechanical properties, compression set, aging resistance, low temperature resistance, glass transition temperature and oil resistance of EBT/NBR blends were studied. The results indicated that with the increase of EBT content, tensile strength, tear strength and elongation at break of the blends decreased gradually, while hardness and modulus increased gradually, and compression set got larger gradually. With the increase of EBT content, the hot-air aging resistance of the blends showed a trend of first decreasing and then increa-sing with improved ozone aging resistance and better low temperature resistance, but the oil resistance decreased. When m（EBT)/m（NBR) was 30/70, the comprehensive mechanical properties and oil resistance of the blend decreased slightly, but the low temperature resistance and ozone aging resistance improved significantly.

The causes and adverse effects of thermal problems in the polymer rubber extrusion process were analyzed, the current research status of thermal management in rubber extrusion at home and abroad in recent years were summarized from the aspects of screw structure optimization, external coo-ling improvement, internal heat transfer enhancement and application of field synergy principle on heat transfer enhancement with 48 references, and prospects were made for the development direction of thermal management in rubber extrusion.

The transfer mechanism and process characteristics of polymer devolatilization were briefly described， and the mechanism and process intensification of devolatilization mass transfer were introduced. The methods of polymer devolatilization process intensification were summarized from the devolatilization equipment and devolatilization process， and it was pointed out that the new devolatilization equipment and process were the key to realize the high-efficiency devolatilization of polymer. The research status and development trend of new technologies of polymer devolatilization， such as supercritical fluid， ultrasonic cavitation and high gravity were emphatically expounded with 62 refe-rences.

The change characteristics of production capacity, output, import and export quantity, apparent consumption of main synthetic rubber pro-ducts of China in 2023 were retrospected, the status of supply and demand of butadiene as well as price changes of main rubber varieties were introduced, and the developing trend of China′ synthetic rubber industry in 2024 was prospected.

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Organic chemistry is a fundamental course for undergraduate students majoring in clinical disciplines at our university, playing a crucial "bridge" role in their subsequent professional courses. However, organic chemistry is known for its abstract theoretical concepts and numerous knowledge points, making it challenging for students to comprehend and master. In response to the teaching issues encountered in traditional classroom settings, this paper adopts the innovative O-PIRTAS flipped classroom model, integrating the characteristics of organic chemistry education. Taking the specific topic of carboxylic acids as an example, the classroom teaching is restructured with the aim of exploring the application of this model in organic chemistry courses and subsequently improving teaching effectiveness. [ABSTRACT FROM AUTHOR]

Flame retardant ceramic silicone rubber was prepared by dehydrogenation condensation using α,ω-hydroxy-terminated polysiloxane as matrix, and composite ceramic powder and fumed silica as fillers. The effects of the amount of composite ceramic powder, type of raw rubber side groups and ablation temperatures on the properties of the flame retardant ceramic silicone rubber were investigated. The results showed that the physical and mechanical properties of 107 silicone rubber containing side methyl group were almost the best when the amount of composite ceramic powder was 120 phr (mass), the tensile strength was 4.69 MPa, elongation at break was 686%, Shore A hardness was 48 and flexural strength was 12.29 MPa. Compared with 107 silicone rubber and 108 silicone rubber containing pendant phenyl group, the ceramic silicone rubber prepared from 109 silicone rubber containing pendant methyl vinyl group had better thermal stability, and the residual carbon mass fraction of composite up to 86% at 1 000 ℃. The ceramic silicone rubber from 109 silicone rubber had better flame retardancy, the limiting oxygen index was 49.5%, and the vertical combustion grade was V-0. In addition, it had a lower ceramization temperature and a good ceramization effect at 600 ℃.

The polymerization behavior of butadiene was studied using a catalytic system composed of modified neodymium neodecanoate [m-Nd(vers)3] as the main catalyst, triisobutyl aluminum as co-catalysts and chlorine sources. The effects of amount of co-catalyst triisobutyl aluminum, chlorine source structure, polymerization temperature and amount of catalyst on the polymerization activity of butadiene, structure selectivity of cis-1,4-unit, molecular weight and its distribution of the polymer were investigated. The results showed that polybutadiene catalysized by m-Nd(vers)3/triisobutyl aluminum/sesquiethyl aluminum chloride system could be obtained with higher catalytic activity, ultra-high content of cis-1,4-unit structure (mole fraction up to 99.2%), high number-average molecular weight (1.19×105 to 4.12×105) and narrow molecular weight distribution (polydispersity index less than 2.5).

Dynamic vulcanized thermoplastic elastomer (TPV)/nickel (Ni) coated glass fiber (NCGF)/vitamin C(VC) composites(TPV/NCGFVC) were prepared by melt blending method. The effects of VC on micromorphology, molecular structure and mecha-nical properties of the composites before and after aging were systematically studied. The mechanism of selective protection of VC on Ni network was discussed. The results showed that the addition of VC in TPV/NCGF composites could effectively inhibit the oxidation of Ni conductive network during the aging process, so that the composites showed stable conductivity and electromagnetic shielding effectiveness with the electromagnetic shielding effectiveness retention rate of over 90%. After VC was introduced into the pure TPV matrix, it could effectively inhibit the fracture of the molecular chain of TPV after thermal oxidative aging. During the aging process of TPV/NCGFVC composite, VC reacted preferentially with the Ni network to reduce the Ni ions generated from by the oxidation of the Ni layer on the surface of NCGF to elemental Ni, indicating that VC had a selective protective effect on the Ni metal network.

"Firstly, Eucommia ulmoides gum (EUG) was epoxidized to obtain epoxidized EUG (EEUG). Then, EEUG grafted silicon dioxide (SiO2) composite (EEUG-g-SiO2) was prepared by wet graf-ting SiO2 onto EEUG. The structure and properties of EEUG-g-SiO2 composite were studied. The results showed that compared with EUG/SiO2 and EEUG/SiO2 mechanical blends, the dispersion of nano SiO2 in EEUG-g-SiO2 vulcanizate was significantly improved and the mechanical properties were greatly improved. Compared with EUG/SiO2 vulcanizates, the tear strength of EEUG-g-SiO2 vulcanizate increased by 30.9%, fatigue resistance increased by 575%, and abrasion decreased by 94%. Compared with EEUG/SiO2 vulcanizate, the tear strength of EEUG-g-SiO2 vulcanizate increased by 10.5%, fatigue resistance increased by 68.6%, abrasion decreased by 72%, and the compression heat build-up decreased significantly."

Butene-based elastomers were prepared by bulk polymerization of butene-1 and he-xene-1 using self-made supported titanium catalyst, and the optimization of polymerization process was studied. The structure of the copolymers was characterized by nuclear magnetic resonance spectrometer and differential scanning calorimetry, and the physical and mechanical properties of the copolymers were investigated. The results showed that the optimum polymerization conditions were as follow：n(monomers)/n(catalyst) was in range of 20 000 to 25 000, n(triethylaluminum)/n(supported titanium catalyst) was in range of 250 to 300, reaction tem-perature was 45 ℃, reaction time was 4 h，hydrogen pressure was in range of 0.10 to 0.15 MPa. The copolymer contained a random copolymer structure of butene-1 and hexene-1. The copolymer had no fixed melting point. The tensile strength and elastic modulus of the copolymer decreased with the increase of the amount of hexene-1, and the nominal fracture strain of the copolymer reached 534% when the mass fraction of hexene-1 was 20%.

trans-polyisoprene(TPI)/organic clay (OC) nanocomposites (TPICNs) were prepared by adding OC into TPI matrix. The crystallisation, shape memory properties, mechanical properties and micromorphology of TPICNs were investigated by X-ray diffraction, differential scanning calorimetry, dyna-mic mechanical analysis and scanning electron microscopy, respectively. The results showed that the crystallinity, tensile strength and shape recovery rate of TPICNs increased first and then decreased with increase of OC content. When the amount of OC was 1.2 phr (mass), the tensile strength of TPICNs was the highest and the shape memory behaviour was the best. The crystalline particles on the fraction surface of TPICNs were uniformly distributed.

In view of main shortcomings of common conveyor belt used in coal mine, a new type of flame retardant conveyor belt with steel mesh core was developed, and the longitudinal tensile strength, bond strength, surface resistance and flame retardant properties of the conveyor belt were studied. The results showed that the average longitudinal tensile strength of the flame retardant conveyor belt with steel mesh core was 1 214 N/mm, the average adhesive strength of working face of the conveyor belt was 13.5 kN/m, and the average adhesive strength of non-working face was 11.4 kN/m. The average surface resistance of working face of the conveyor belt was 3.3×106 Ω, and the average surface resistance of non-working face was 4.8×106 Ω. The average glowiag time and leach-resitant of the conveyor belt with complete cover were not more than 3.0 s, and the average glowiag time and leach-resistant of the conveyor belt without cover were not more than 5.0 s. The indicators of the developed conveyor belt met the relevant provisions of the current major industry standards.

A method was developed for the simultaneous analysis of trace arsine and phosphine in ethylene and propylene products by gas chromatography-atomic emission spectroscopy detector and the chromatographic analysis conditions were optimized, and the detection limit, linear range, recovery rate and repeatability of the method were investigated. The results showed that the detection limit of the method for arsine was as low as 0.02 mL/m3, the linear correlation coefficient was more than 0.999 in the volume concentration range of 0.02~2 090 mL/m3, the recovery rate was 87.60% and the relative standard deviation of the 3 parallel measurements was 1.83%. The detection limit of phosphine was as low as 0.03 mL/m3, the correlation coefficient was greater than 0.999 in the volume concentration range of 0.03~3 010 mL/m3, the recovery rate was 106.13% and the relative standard deviation of the 3 parallel measurements was 3.39%. The method can be used as a control analysis method for trace arsine and phosphine in ethylene and propylene products.

Chloroprene rubber was vulcanized with 1,2-ethylenethiourea as accelerator, zinc oxide and magnesium oxide as vulcanizing agents. The non-isothermal vulcanization kinetics of chloroprene rubber was studied by differential scanning calorimetry, the kinetic parameters of vulcanization reaction were calculated by Kissinger and Crane equations, and the kinetics of isothermal vulcanization reaction was studied by vulcanizer method and the apparent activation energy at the thermal vulca-nization stage was calculated. The results showed that the n-order kinetic model could describe the non-isothermal vulcanization process of chloroprene rubber effectively. The apparent activation energy of the vulcanization reaction was 92.78 kJ/mol and the reaction order was 0.93. The isothermal vulcanization process of chloroprene rubber could be divided into 3 stages: scorching stage, thermal vulcanization stage and flat vulcanization stage. The thermal vulcanization stage followed the first-order reaction kinetics and the apparent activation energy of the thermal vulcanization stage was 53.38 kJ/mol.

Tea polyphenol stearate was prepared by esterification of tea polyphenols and stearic acid, and its anti-aging behavior of cis-1,4-polybutadiene rubber (BR) was studied. The results showed that the compatibility between tea polyphenol stearate and BR matrix was good, and the blooming effect was inhibited. Compared with tea polyphenols, the initial tensile strength and elongation at break of BR were increased by tea polyphenol stearate, while the Shore A hardness and crosslinking density were decreased, and the physical and mechanical properties of BR after aging for 10 d were similar to those of BR with aniline antioxidant 4010 NA. Tea polyphenols before and after modification could inhibit significantly the cis- and trans- isomerization effect of BR in the aging process, and its effect was much better than that of antioxidant 4010 NA.

High fluorine content fluororubber (FKM) was used as the research object, the high temperature medium resistance of high fluorine content FKM vulcanizates in a variety of aero-engine lubricanting oils was investigated, and the changes in physical and mechanical properties of high fluorine content FKM vulcanizates caused by different types of lubricanting oils were studied. The results showed that the high fluorine content FKM vulcanizates could still maintain good compression resilience after aging in lubricating oil at 200 ℃ for 72 h, the volume change rate was lower than 12%, the mechanical properties declined slightly, and the Shore A hardness decreased significantly. The mechanical pro-perty attenuation and volume change rate of high fluorine content FKM vulcanizate were different for different kinds of oil. The corrosion of lubricating oil on high fluorine content FKM vulcanizate at high temperature included physical infiltration and che-mical corrosion.

The effects of bound acrylonitrile content, curing system, reinforcing system and plastici-zing system on the corrosion resistance of nitrile rubber (NBR) to common chemical media in the field of petroleum exploitation were studied. The results showed that with the increase of bound acrylonitrile content, the physical and mechanical properties and thermal air aging resistance of NBR vulcanizates increased, the resistant to non-polar media such as kerosene and submarine control fluid was better, the resistance to methanol, distilled water and ethylene glycol aqueous solution decreased gradually, and the resistant to acid, alkali and brine had little diffe-rence. The curing system affected mainly the physical and mechanical properties and heat air aging resistance of NBR vulcanizates, and had little effect on the resistance of NBR vulcanizates to various petroleum exploitation media. For the high hardness NBR vulcanizates, the physical and mechanical properties of the vulcanizates were the best when small particle size carbon black was used as reinforcing system, and the effect of different reinforcing system on the heat air aging resistance of NBR vulcanizates was not obvious. However, the vulcanizates had better resistance to methanol and kerosene when large particle size carbon black was used as a reinforcing filler, and inert reinforcing filler should be selected. The physical and mechanical properties of NBR vulca-nizates added with macromolecule ester plasticizer were better than those with small molecule ester plasticizers and liquid NBR plastici-zer, and the heat air aging properties were similar, but the volume change of resistance to various media was larger, and the resistance to methanol, kerosene and 10% sodium hydroxide solution were poor, while the resistance to other petroleum exploitation media were less affected.

The effects of self-made nano particles titanium dioxide (TiO2) and iron-doped titanium dioxide (TiO2/Fe2O3) as heat-resistant additives on thermal stability and tensile properties of fluorosilicon rubber after hot air aging were studied. The decomposition products of fluorosilicon rubber at 5% weight loss in air and the content of characteristic groups of fluorosilicon rubber before and after thermal aging were analyzed. The effects of commercial heat-resistant additives, such as nano ceria (CeO2), ferric oxide (Fe2O3) and aluminum trioxide (Al2O3) on fluorosilicone rubber were compared. The results showed that when the mass fraction of nano heat- resistant additive was 2%, the 5% weight loss temperature of fluorosilicone rubber in air from high to low was TiO2/Fe2O3, TiO2, Fe2O3, CeO2, Al2O3 samples and blank sample. The 5% weight loss temperature of fluorosilicone rubber with nano-TiO2/Fe2O3 heat-resistant additive reached 453 ℃, which was 47 ℃ higher than that of blank sample. Nano-TiO2/Fe2O3 heat-resistant additive could significantly inhibit oxidation of fluorine-containing side groups of fluorosilicone rubber, which was the main reason for improvement of the heat resistance of fluorosilicone rubber.

The evolution of structure and properties of natural rubber (NR) for vibration damping products during storage was studied by long-term storage method and accelerated aging method. The results showed that the hardness, modulus at 100%, modulus at 300%, storage modulus and loss modulus of NR vulcanizates increased gradually with increase of aging temperature and aging time, and the overall change trend was similar to that of crosslinking density. The change rates of tensile strength and elongation at break decreased while the loss factor decreased rapidly and tended to be stable. The ratio of dynamic stiffness and static stiffness decreased first and then increased slowly. Hot air aging had little effect on the vibration reduction performance of NR vulcanizates.