Applied Theory

• ZHAO Tao,DENG Daoyu,Wang Hongzhen,GUI Hongxin and XIN Zhengxiang
• Effect of Alkaline Protease Coagulation of Natural Latex on Structures and Properties of NR

• 2025 Vol. 72(8): 0572-0579

  [Abstract](39)

  [PDF](22)

• Abstract:The effect of alkaline protease coagulation of natural latex on the non-rubber component contents of natural rubber（NR） and the vulcanization characteristics，physical properties and processing properties of NR compound was studied.The results showed that with the increase of alkaline protease dosage，some proteins and phospholipids in natural latex were hydrolyzed，leading in a decrease in the nitrogen content of NR and an increase in the acetone extract content.Compared with acid coagulation NR pure compound，alkaline protease coagulation NR pure compound had an significantly faster vulcanization rate and larger crosslinking density，tensile stress at 300% elongation，tensile strength and tear strength.Compared with acid coagulation NR/carbon black N330 composite，alkaline protease coagulation NR/carbon black N330 composite had lower compression heat build-up and significantly better wear resistance，but larger Payne effect.

• LIU Xiaoxia,LI Rongxun and LI Chaoqin
• Study on stress-strain behavior of SBR Vulcanizates Reinforced with carbon black N330

• 2025 Vol. 72(8): 0580-0585

  [Abstract](34)

  [PDF](26)

• Abstract:The stress-strain behavior of styrene-butadiene rubber（SBR）vulcanizates reinforced with carbon black N330 was studies based on uniaxial tensile tests，the real stress of SBR vulcanizates was obtained by correcting the cross-sectional area of the specimens during stretching，and the BEDA model was employed to simulate the engineering stress-strain and real stress-strain curves of SBR vulcanizates.The results showed that the real stress of SBR vulcanizates was greater than the engineering stress，with the increase of carbon black N330 amount，the ratio of real stress to engineering stress gradually increased.When the carbon black N330 amount was 40 phr，the real stress of SBR vulcanizates was 248.24 MPa，and the engineering stress was 28.24 MPa.When the carbon black N330 amount ranged from 10 to 20 phr，a percolation phenomenon was observed in both the engineering stress and real stress of SBR vulcanizates.When the strain was 100%～600%，the simulated engineering stress-strain and real stress-strain curves of the BEDA model for SBR vulcanizates coincided well with the corresponding experimental curves，and the fitting parameters of the real stress-strain curve were greater than those of the engineering stress-strain curve.

Material · Compounding

• Wang Fan,Liu Weidong,Song Fang,Zhang Jinfeng,Min Huihai and Yao Weidong
• Effect of Accelerators on Properties of EPDM Compounds

• 2025 Vol. 72(8): 0586-0590

  [Abstract](40)

  [PDF](30)

• Abstract:The effects of dithiocarbamate type accelerators，thiuram type accelerators and sulfonamide type accelerators and their blending on the properties of ethylene-propylene-diene rubber（EPDM） compounds were studied.The results showed that the dithiocarbamate type accelerator ZDEC improved the overall performance of the compound.When blending with other accelerators，the thiuram type accelerator TETD had higher vulcanization activity，and the compound had better scorch safety.The sulfonamide type accelerator CBS had good scorch safety and post effect，and could be used as a secondary accelerator in rapid vulcanization systems.The accelerators ZDEC/TETD/CBS blending could effectively reduce the reaction activation energy of the compound and shorten the vulcanization time，and make the compound have good scorch safety and vulcanization flatness.The physical properties of the compound with accelerator ZDEC，TETD and CBS blending were equivalent.

• zhangsong and DU Wei
• Effect of Petroleum Resin Types on Properties of NR/NBR/PB-3000 Blends

• 2025 Vol. 72(8): 0591-0594

  [Abstract](27)

  [PDF](19)

• Abstract:The effect of petroleum resin types [C5 petroleum resin，C9 petroleum resin and C5/C9 copolymer petroleum resin] on the properties of natural rubber（NR）/nitrile rubber（NBR）/functional polybutadiene（Powdered maleic anhydride grafted polybutadiene）（PB-3000） blends was investigated.The results showed that petroleum resin could reduce the vulcanization rate and crosslinking density of the blend，and improve the processing performance.Compared with the blend without petroleum resin，the hardness and tensile stress of the blend with petroleum resin decreased，the elongation at break increased，and the tensile strength changed little.The influence of petroleum resin types on the hardnesses，tensile stresses and elongations at break of the blend varied significantly，while the influence on tensile strengths was not significantly different.The shear modulus and horizontal equivalent stiffness of the blend with petroleum resin decreased，and the damping performance was improved.As the benzene ring content in petroleum resin increased，the tensile stress at a given elongation of the blend decreased，the elongation at break increased，the reduction rate of the shear modulus and horizontal equivalent stiffness increased，but the influence of petroleum resin types on the damping performance of the blend was not significantly different.

Product · Design

• SUN Hongyang,WANG Wenjun,GUO Dongdong,SA Lei and LING Rongliang
• Effect of Tire Wear on Vehicle Performance

• 2025 Vol. 72(8): 0595-0601

  [Abstract](44)

  [PDF](34)

• Abstract:Under the same driving condition and mileage，the wear degrees of tire from five brands were studied，wet braking performance，dry braking performance and interior noise tests were conducted on both new and worn tires from different brands to explore the effect of tire wear on vehicle performance.The results showed that the wet braking distance of worn tire was greater than that of new tire，the dry braking distance was less than that of new tire.The interior noise of worn tire was greater than that of new tire，and with the vehicle speed increased，the noise growth rate of worn tire was greater than that of new tire，indicating that tire wear led to increase interior noise.

Technology · Equipment

• GE Fuyu,LI Li,WANG Yiyuan,LI Xiaochen,HAN Wenwen and WANG Chuansheng
• Heat Transfer Analysis of Rubber Hose during Vulcanization Process

• 2025 Vol. 72(8): 0602-0606

  [Abstract](33)

  [PDF](25)

• Abstract:The simulation and analysis of heat transfer of the rubber hose during vulcanization process by finite element analysis software were carried out.The results showed that as the extension of vulcanization time，the temperature differences of various parts of the rubber hose gradually decreased.After vulcanization for a certain period of time，the temperatures of various parts of the rubber hose were almost the same，and the heat transfer of the rubber hose reached a balanced state.Reasonably increasing the inital temperature of the rubber hose could effectively short vulcanization time of the rubber hose.

• XIN Jinwei,MA Zichen,WANG Yupeng,JIAN Ranran,ZENG Xiankui and MAIO Qing
• Optimization Design of Screw Structural Parameters of Rubber Injection Molding Machine and It’s Finite Element Simulation Analysis

• 2025 Vol. 72(8): 0607-0614

  [Abstract](32)

  [PDF](24)

• Abstract:To solve the problem of poor plasticizing quality of the compound in rubber injection molding machine，the optimization design and finite element simulation analysis of the structural parameters of the screw were carried out.Based on the structural parameters of the 522C008 screw，the optimized design 522C03901 screw maintained the same length-to-diameter ratio，while the geometric compression ratio，helix angle，pitch，groove depth and rib width were reduced.Finite element simulation analysis and test verification revealed that，compared with the 522C008 screw，during the injection molding process of the compound，the maximum plosticizing temperature，average outlet temperature and maximum outlet temperature of the 522C03901 screw increased，average outlet pressure was improved.The injection molded rubber strip displayed a smooth surface without scorching，indicating that the 522C03901 screw delivered superior plasticizing effect.

Testing · Analysis

• LI Zhaoyang,BIAN Huiguang,CHEN Hailong,CHENG KUN and WANG Chuansheng
• Online Prediction of Mooney Viscosity of NR Compound based on Convolutional Neural Network

• 2025 Vol. 72(8): 0615-0620

  [Abstract](29)

  [PDF](17)

• Abstract:To solve the issues of time lag and operational complexity in the detection of the Mooney viscosity [ML(1+4) 100 °C] （referred to as Mooney viscosity） of natural rubber （NR） compound，a method for online prediction of the Mooney viscosity of NR compound based on a convolutional neural network （CNN） was proposed.The parameters recorded by internal mixer during the compounding process，such as the chamber temperature，mixing time，material temperature，rotor speed and torque，Mooney viscosity of plasticated rubber were organized into a matrix as input，with the Mooney viscosity of the compound as output，the CNN prediction model for the Mooney viscosity of NR compound with complex mapping relationship from input to output was constructed.The results showed that the CNN prediction model for the Mooney viscosity of NR compound was essentially convergent，with a mean square error of 0.5 between the predicted and measured values of the Mooney viscosity.The correlation coefficient（ R²） of the CNN prediction model was 0.874 3，with a recognition rate of 88.46% for prediction errors within Root number 5 ，and with a recongnition rate of 42.30% for prediction errors within Root number 2.The CNN prediction model demonstrated high indentification accuracy in predicting the Mooney viscosity of NR compounds within the range of 45～75 of Mooney viscosity of plasticated rubber.

• ZHANG Yanlong,LI Kuiguan,CHENG Xianbin,YIN Haijian and JING Tao
• Application of Free Modal Test Analysis in Solving Shaking of All-steel Off-The-Road Radial Tire

• 2025 Vol. 72(8): 0621-0626

  [Abstract](34)

  [PDF](18)

• Abstract:The cause of the shaking of all-steel off-the-road radial tire for airport rescue fire truck during high-speed driving was analyzed，and the solutions were proposed.Through free modal test analysis and experimental verification，it was determined that the cause of the shaking of the tire was that the natural vibration frequency of the tire was consistent with vehicle traveling at a speed above 80 km·h-1，so that the tire resonated with vehicle.By adjusting the joint positioning angles of semi-finished components and optimizing material distribution，the problem of the shaking of the tire was solved，and the comfort performance of airport rescue fire truck was improved.

• LIU Qingzheng and GE Jianmin
• Simulation and Experimental research on tire near-field noise based on circular sound source

• 2025 Vol. 72(8): 0627-0631

  [Abstract](29)

  [PDF](21)

• Abstract:The simulation and experimental research of the tire near-field noise based on circular sound source was introduced.The finite element simulation calculations of the tire noise sound pressure level were respectively carried out by using the circular sound source model and the equivalent point sound source model，and the tire noise sound pressure level test was conducted.The results showed that，the error between the simulation valve of the tire noise total sound pressure level calculated by circular sound source model and the test value was －1.3 dB（A），and the error between the simulation valve of the tire noise total sound pressure level calculated by the equivalent point sound source model and the test value was ＋2.9 dB（A）.The simulation results of the tire noise by the circular sound source model were more reliable，and the finite element simulation of the circular sound source could provide guidance for the low-noise tire design.

Comprehensive and Special Review

• ZHAO Zhihui,XIAO Jianbin,ZHUANG Peng,LI Yingyu and WANG Xufeng
• Research Progress of EPDM Automobile Sealing Strips with Low Odor and Low VOC

• 2025 Vol. 72(8): 0632-0639

  [Abstract](40)

  [PDF](30)

• Abstract:Ethylene-propylene-diene rubber（EPDM） had become the main material for automotive sealing strips due to its excellent aging resistance.This paper reviewed the research progress of EPDM automotive sealing strips with low odor and low volatile organic compounds（VOC），overviewed the optimization of the compound formulas，processing techniques and post-treatments that could achieve this purpose，briefly introduced the current testing methods for odor and VOC of EPDM sealing strips，and pointed out the future research directions of EPDM sealing strips.

Special Contribution

• SUN Jiafeng,ZHU Yanming and WU Mingsheng
• Reinforcement Performance of Eucalyptus Lignin on NR

• 2025 Vol. 72(8): 0563-0571

  [Abstract](37)

  [PDF](22)

• Abstract:The reinforcement performance of eucalyptus lignin on natural rubber（NR） was studied.The results showed that eucalyptus lignin had poor reinforcement performance on NR，inferior to traditional reinforcement agents such as kaolin，calcium carbonate，carbon black N660 and silica，but its vulcanizate had a small compression set.Under the condition of keeping the total amount of reinforcing agent unchanged，replacing 10 phr of carbon black N660 or 30 phr silica with equal amounts of eucalyptus lignin did not significantly reduce the mechanical properties of the vulcanizates，but significantly reduced the compression set.