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  • Theory and Research
    HU Peng, YANG Tian-Tian, HE Long-qiang, TANG Si-Min
    Plastics Science and Technology. 2024, 52(07): 28-32. https://doi.org/10.15925/j.cnki.issn1005-3360.2024.07.006

    Water-absorbent resins have attracted widespread attention in the field of environmental treatment due to their ability to adsorb metal ions. The article utilizes corn straw and kaolin as raw materials, and acrylate and acrylamide as polymerization monomers to prepare cellulose-based superabsorbent resin through an aqueous solution polymerization method. The cellulose-based superabsorbent resin was characterized using Fourier transform infrared spectroscopy (FTIR), scanning electron microscopy (SEM), and energy-dispersive X-ray spectroscopy (EDX). The synthesized superabsorbent resin was utilized for the adsorption study of Cd2+ in simulated wastewater. The results showed that the cellulose-based superabsorbent resin exhibited excellent adsorption capacity for Cd2+. When the solution pH value was 6, the resin dosage was 0.10 g, and the adsorption time was 200 min, the effective removal rate of the superabsorbent resin for Cd2+ could reach 93.57%. The resin demonstrated good desorption performance for Cd2+ in dilute hydrochloric acid solution, with a desorption rate of 88.73%. The resin also exhibited good reusability, maintaining a Cd2+ removal rate of 79.12% after eight cycles of repeated adsorption. The cellulose-based superabsorbent resin possesses recyclable and regenerative capabilities, with good stability in repeated adsorption, and has potential value for the treatment of industrial wastewater containing Cd2+.

  • Physical and Chemical Tests
    CUI Ping, CAO Qing-feng, DING Yi -mei
    Plastics Science and Technology. 2024, 52(08): 126-131. https://doi.org/10.15925/j.cnki.issn1005-3360.2024.08.025

    This paper established a high performance liquid chromatography (HPLC) method for the determination of ultraviolet absorber UV-P in an light resistant thermoplastic polyurethane infusion device, and to carry out the research on the dissolution of ultraviolet absorber UV-P from disposable TPU infusion device. Six different types of injections were used to simulate the clinical application conditions, and after infusion with a light resistant TPU infusion device, they were analyzed by high-performance liquid chromatography. Kromasil C18 column was adopted, the mobile phase consisted of methanol-water (90∶10), the detection wavelength was 339 nm. The resuls show that calibration curves of UV-P are linear over the range of 0.061 4~1.638 0 mg/L (r=0.999 9), the average recoveries are both betwen 97.91% and 101.10%, the relative standard deviation is less than 2%, the signal-to-noise ratio is greater than 3, and the values of quantitation limit is 0.020 48 mg/L.The method is sensitive and good repeatability, which is suitable for the detection of UV-P dissolution in TPU infusion device.

  • Computer Aided Technology
    ZHANG Su-xin
    Plastics Science and Technology. 2024, 52(08): 109-112. https://doi.org/10.15925/j.cnki.issn1005-3360.2024.08.021

    In the design of plastic solutions for electronic relays, the maximum deformation after injection molding is a key parameter that needs to be controlled. This article conducts a simulation study on the injection molding and deformation of an ABS electronic relay housing. Obtain the optimal gate position through flow resistance and gate matching analysis, and establish a hot runner system based on this. Orthogonal test analysis shows that for deformation, the influence of holding time is extremely significant, the influence of barrel temperature and mold cavity temperature is significant, and the influence of injection time is not significant. The optimized process parameter combination A2B3C1D3 (mold cavity temperature 45 ℃, barrel temperature 250 ℃, holding time 14 s, and injection time 0.9 s)was obtained by observing the curve of maximum deformation changing with the process level. The simulation verification of the optimized process found that the maximum deformation was reduced from 0.341 0 mm to 0.212 8 mm, with an optimization rate of 37.6%, and the filling state, appearance, injection pressure all met the requirements.

  • Processing and Application
    LIN Yu, YU Jia-ming, HAN Meng-yao, LI Chun-feng, LIU Ming-li
    Plastics Science and Technology. 2024, 52(08): 89-94. https://doi.org/10.15925/j.cnki.issn1005-3360.2024.08.017

    In order to optimize the process parameters of the mechanical properties of PP/corn straw composites and further optimize the preparation process, the orthogonal test design of L 16(44) was used to prepare PP/corn straw composites under different process parameters. The effects of wood-plastic ratio, hot pressing temperature, hot pressing time and hot pressing pressure on the mechanical properties of PP/corn straw composites were analyzed. The results showed that the wood-plastic ratio had the greatest influence on the mechanical properties of PP/corn straw composites among the four factors of wood-plastic ratio, hot pressing temperature, hot pressing time and hot pressing pressure. Secondly, the hot pressing pressure has a great influence on the flexural strength and impact strength of PP/corn straw composites, and the hot pressing temperature has a great influence on the tensile strength of PP/corn straw composites, the hot pressing time has the least influence on the properties of PP/corn straw. When the ratio of wood to plastic is 4∶6, the hot pressing temperature is 185 ℃, the hot pressing time is 10 min, and the hot pressing pressure is 2.5 MPa, the flexural strength is the maximum value of 39.58 MPa, and the impact strength is the smallest. When the ratio of wood to plastic is 4∶6, the hot pressing temperature is 185 ℃, the hot pressing time is 15 min, and the hot pressing pressure is 2.5 MPa, the tensile strength is 17.18 MPa. When the ratio of wood to plastic is 3∶7, the hot pressing temperature is 190 ℃, the hot pressing time is 15 min, and the hot pressing pressure is 2.5 MPa, the impact strength is the maximum value of 3.94 kJ/m2, and the flexural and tensile strength are the smallest. By comparing the mechanical properties of these three processes, without considering the focus, the optimal preparation process was obtained as follows∶wood-plastic ratio 4∶6, hot pressing temperature 185 ℃, hot pressing time 15 min, hot pressing pressure 2.5 MPa.

  • Review
    XIANG Mai-qi, GONG Xiao-qin, ZHANG Gui-xiang, CAI Xing-ran, MA Zhong-jie, YANG Yan
    Plastics Science and Technology. 2024, 52(08): 151-155. https://doi.org/10.15925/j.cnki.issn1005-3360.2024.08.029

    With the increasing global plastic pollution crisis, identification methods of airborne microplastic particles have been regarded as a crucial issue. This paper reviewed the progress made in this area in recent years. Commonly used air sample collection methods were described, including passive sampling and active sampling. Sample preparation methods, such as sieving, digestion, and density separation were discussed. Besides, microplastic particle identification methods, such as microscopic observation, Fourier transform infrared spectroscopy, and Raman spectroscopy were highlighted. However, there are still some challenges in the existing identification methods, such as the number and size distribution of microplastic particles. Future researches focused on the development of sensitive detection and databases establishment to enable large-scale monitoring were suggested. It was also recommended to establish complete and standardized airborne microplastic sampling and analysis technology. The present review concludes the current status of identification methods for airborne microplastic particles and point outs an outlook on future development directions, which provides a theoretical basis for the control of atmospheric microplastic pollution.

  • Review
    ZHAO Hui-ying, LI Wei, LIU Feng-jie, XIONG Jian, LÜ Xue-bin
    Plastics Science and Technology. 2024, 52(07): 141-146. https://doi.org/10.15925/j.cnki.issn1005-3360.2024.07.030

    In order to reduce the environmental pollution caused by plastic waste, research is being conducted on the photocatalytic degradation and recycling of plastics, utilizing the degradation mechanism of solar photoinitiation and photocatalysis to convert plastics into water and carbon dioxide, or further into hydrogen fuel and high-value chemicals. The article introduces the effects of catalyst characteristics, plastics, and degradation conditions on photocatalytic degradation, summarizes the applications of different types of inorganic metal, non-metal materials, and organic-inorganic composite photocatalysts in photocatalytic degradation and recycling, and aims to improve photocatalytic efficiency through catalyst modification and synergistic effects with electrocatalysis, thermocatalysis, and biocatalysis. The article points out the problems in the pre-treatment and post-treatment of photocatalytic degradation plastic recycling technology, providing a reliable basis and research direction for the recycling and treatment of waste plastics.

  • Review
    WANG Xiang-peng, GAO Yi-lun, LI Yan-ru, LIU Qing-lin, ZHANG Hao-teng, ZHENG Yun-xiang, CHEN Chun-mao
    Plastics Science and Technology. 2024, 52(07): 135-140. https://doi.org/10.15925/j.cnki.issn1005-3360.2024.07.029

    Carbon-based materials have large specific surface area, well-developed pores, and a large number of oxygen-containing functional groups on the surface, which have excellent mechanical properties. Introducing carbon-based materials into the hydrogel system can increase adsorption sites, improve mechanical properties, enrich network structure, realize complementary advantages, and overcome performance defects, which is the main idea for developing high-performance hydrogel adsorbents. In this paper, the structural characteristics of different types of carbon based composite hydrogels were summarized, and the mechanism of carbon based materials to enhance the performance of hydrogels was emphatically introduced. The preparation methods of composite hydrogels and their applications in the field of water purification were reviewed. The prospects, limitations and future research potential of carbon based composite hydrogels adsorbents were analyzed.

  • Processing and Application
    WANG Cai-hua, LIU Shuai, SHANG Ze-yang, GAO Li-bin
    Plastics Science and Technology. 2024, 52(08): 95-101. https://doi.org/10.15925/j.cnki.issn1005-3360.2024.08.018

    Epoxy resin/hollow glass beads-chopped basalt fiber (EP/HGM-CBF) composite foam materials with different fiber mass fractions of CBF were prepared. The effects of the solution corrosion environment on the compression properties of the specimens were investigated by immersing the composite foam material specimens in distilled water, seawater, and seawater with five times the concentration of the compounds, and the causes were analyzed by combining scanning electron microscope photographs and EDS energy spectrometry. The study shows that the moisture absorption rate of the specimen first increases and then decreases with the increase of fiber mass fraction, and the moisture absorption rate is the largest at 10% fiber mass fraction, and the moisture absorption rate is larger in distilled water than in seawater, and the increase of the particle concentration in the solution decreases the diffusion coefficient of the solution. In the solution-immersed corrosive environment, the compression properties of EP/HGM-CBF composite foams all increased with the increase of CBF mass fraction, and reached a maximum when the CBF mass fraction was 30%, and the greatest increase in compression strength and compression modulus was seawater with five times the concentration of the compounds, and the compression strength was increased by 28.4% compared with that of the specimens without CBF. The solution corrosive environment decreased the compressive mechanical properties of the specimens, and the damage forms of the composites were different in the distilled water and seawater environments; the distilled water environment was mainly physical damage such as the dissolution of resin leading to interfacial debonding, whereas the seawater environment was mainly chemical damage due to the dissolution of the interfacial structure by elemental Cl.

  • Process and Control
    GAI Di, FENG Xue-jian, ZHANG Lei, XU Hai, ZHAO Zheng
    Plastics Science and Technology. 2024, 52(10): 119-124. https://doi.org/10.15925/j.cnki.issn1005-3360.2024.10.024

    Mechanical connection, as the main connection method at present, holes shall be made on the surfaces of connectors and connected parts, and the mechanical properties of the structural parts containing holes will be decreased to a certain extent. In order to study the tensile properties of carbon fiber reinforced polymer (CFRP) laminates with different width-to-diameter ratios under humid-heat environments, CFRP laminates containing center penetration holes with diameters of 1, 2, 3, 4, 5 mm, respectively, were prepared, and their damage morphology, stress-strain curves, and strength degradation were analyzed at 71 ℃ and 85% RH. The results show that the CFRP laminates in the room temperature dry (RTD) environment have a flat fracture with the basic characteristics of brittle fracture; the CFRP laminates in the elevated temperature wet (ETW) environment have the phenomena of interlayer delamination and fiber adhesion fracture, and delayed fracture occurs in the tensile process of the test pieces; the tensile strengths of the test pieces in the RTD and ETW environments decrease with the increase of the pore diameters. The tensile strength of the specimens in both RTD and ETW environments decreases with increasing pore size. In order to predict the tensile properties of porous laminates under humid and hot environments, a prediction formula based on the PSC criterion is proposed.

  • Plastic Machinery and Mold
    CHEN Chong, YANG Qingliu, SONG Yunxiao, KANG Xinyu, YIN Kaimei, CHEN Zihao
    Plastics Science and Technology. 2025, 53(02): 142-145. https://doi.org/10.15925/j.cnki.issn1005-3360.2025.02.026

    The mold flow simulation technology was used to simulate the injection molding process of the filter core skeleton of the oil suction filter, and the causes of the defects such as filling and warping were analyzed and the corresponding solutions were provided. The mold cavity designtook the form of having two cavities inside a core, the raw material was selected 30% glass fiber reinforced nylon resin, and the improved scheme matched the appropriate injection molding process parameters for the filter framework. The experimental results showed that double gate and "H" runner had more advantages than single gate and "Z" runner in selecting injection type and reducing warpage of parts. In the optimization scheme, the maximum injection pressure was only 75 MPa, the filling time was only 0.94 s, and the overall deformation was 0.35 mm, which met the requirements of general product size deviation, and the optimization effect was more obvious. The simulation results of the filling process were good, and the appearance and deformation measurement results of the test pieces were qualified, which verified the feasibility of the optimization parameters.

  • Plastics Science and Technology. 2025, 53(04): 9-14. https://doi.org/10.15925/j.cnki.issn1005-3360.2025.04.002
    以4,4'-(六氟异丙烯)二酞酸酐(6FDA)和2,2'-双(三氟甲基)-4,4'-二氨基联苯(TFMB)为反应单体,通过化学-热混合亚胺化法制备聚酰亚胺(PI)薄膜。先在前驱体聚酰胺酸(PAA)中加入不同含量的乙酸酐和吡啶进行化学亚胺化,原位引入刚性酰亚胺环结构,制备不同亚胺化程度的酰胺酸-酰亚胺共聚物(PA-I)薄膜,再通过热亚胺化法制备无色透明的聚酰亚胺(PI)薄膜。采用傅里叶变换红外光谱仪(FTIR)、紫外可见分光光度计、乌氏黏度计、动态机械热分析仪(DMA)、热重分析仪(TG)和万能材料试验机等方法对薄膜进行表征。结果表明:随着乙酸酐和吡啶含量的增大,刚性酰亚胺环结构增多,PA-I共聚物薄膜亚胺化程度增大,最终经热亚胺化制备的PI薄膜分子链排列的有序程度增大;力学性能和耐热性能随着刚性酰亚胺环结构的增多而增大,光学性能随着刚性酰亚胺环结构的增多呈现先增高后降低的趋势。当共聚物薄膜的化学亚胺化程度为60%时制备的PI薄膜的综合光学性能最佳,在500 nm处的透光率达到88.66%,黄度指数仅为5.9;其力学性能较好,拉伸强度达到121.3 MPa,拉伸模量为3.11 GPa,断裂伸长率为5.165%。
  • Plastics Science and Technology. 2025, 53(04): 1-8. https://doi.org/10.15925/j.cnki.issn1005-3360.2025.04.001
    制备3种含有不同取代基的双水杨醛钴(Ⅱ)配合物,通过红外光谱、质谱以及X-射线单晶衍射对其结构进行表征。以偶氮二异丁腈(AIBN)为自由基引发剂研究含有不同取代基的水杨醛钴配合物介导的醋酸乙烯酯(VAc)聚合反应,探究[AIBN]/[Co]、单体浓度、反应时间和温度对聚合物分子量以及分子量分布的影响。结果表明:配合物1与AIBN在本体聚合与溶液聚合中均表现出较好的催化效果。当[VAc]/[AIBN]/[1]为600/2/1时,在65℃的甲苯溶液中进行聚合反应20 h,所得聚醋酸乙烯酯的数均分子量与理论分子量接近,分子量分布较窄。
  • Plastic Machinery and Mold
    YAO Lei, FAN Xin-yu, REN Jian-nan, YANG Hong-jian, LI Chen-xi, SHI Li-shuo, LI Qi-zhi
    Plastics Science and Technology. 2024, 52(08): 117-120. https://doi.org/10.15925/j.cnki.issn1005-3360.2024.08.023

    A lightweight water-soluble core mold material for hollow shell composites was prepared by hot drying process with polyvinylpyrrolidone (PVP) aqueous solution as the adhesive and hollow glass microspheres as the matrix material. The effects of the content of adhesive and different treatment methods on the flexural strength, compressive strength and dissolution rate of the core mold were studied, and the microstructure of the core mold material was observed by scanning electron microscope. The results show that adhesive dosage of 40%, the flexural strength and compressive strength could reach up to 3.346 MPa and 3.499 MPa, with a water solubilization rate of 0.238 g/s. After the coupling agent treatment and high temperature treatment, the core mold strength and dissolution rate are improved, and the modification effect is good; small filler sizes can effectively fill the gap formed by matrix materials accumulation, improve the mechanical strength and affect the water solubility rate. The properties of water-soluble core can meet the requirements of resin transfer molding (RTM) and vacuum bag molding, which provides a solution for the integrated molding of profiled hollow profiles.

  • Computer Aided Technology
    LOU Yan-hua, XU Li-li
    Plastics Science and Technology. 2024, 52(08): 113-116. https://doi.org/10.15925/j.cnki.issn1005-3360.2024.08.022

    The material used for the pipeline distributor is polyamide66 (PA66), which is made by injection molding process and analyzed by molding flow by Moldflow software, and the injection molding process is affected by many factors. In this paper, the melt temperature, injection pressure, holding pressure and cooling time are taken as the research variables, and the warpage deformation of the parts is taken as the research objective to establish the response surface model, so as to reduce the warpage deformation of the parts by obtaining a set of better combinations of molding process parameters. The results show that when the melt temperature is 238 ℃, the injection pressure is 50 MPa, the holding pressure is 30 MPa and the cooling time is 110 s, the warpage deformation of the parts is 2.264 0 mm, which is reduced by 2.118 7 mm compared with before optimization, and the overall quality is significantly improved.

  • Processing and Application
    ZHANG Guo-ping, ZHU Wen-jun
    Plastics Science and Technology. 2024, 52(08): 102-104. https://doi.org/10.15925/j.cnki.issn1005-3360.2024.08.019

    Silicon dioxide(SiO2) nanoparticles were modified using aminosilane coupling agents (GAS), and the modified SiO2 nanoparticles were used to enhance the dielectric and mechanical properties of PVC nanocomposites. The effects of the addition of modified SiO2 nanoparticles on them were studied. The results showed that with the increase of modified SiO2, the relative dielectric constant of PVC composites shows a trend of first decreasing and then increasing, and reaches the lowest value of 2.97 at 1.5% addition, which is 26.12% lower than that of pure PVC materials. The breakdown strength of PVC composites shows a trend of first increasing and then decreasing under both direct current and branch electric fields, with the highest breakdown strength reached at a addition of 1.0%. The breakdown strength under direct current and branch electric field conditions is 70.21, 60.12 kV/mm, respectively, and the breakdown strength of pure PVC materials has increased by 20.48% and 30.36%, respectively. In addition, at a addtion of 1.0%, the tensile strength, flexural strength and elongation at break of PVC composites are 49.33 MPa, 92.67 MPa and 187.34%, respectively.

  • Processing and Application
    DUAN Bing-bing, WEI Zhang-dong, WANG Lin
    Plastics Science and Technology. 2024, 52(08): 83-88. https://doi.org/10.15925/j.cnki.issn1005-3360.2024.08.016

    Microplastic pollution has become a concern around the world, when microplastics interact with other pollutants such as heavy metals in the soil system, microplastics will adversely affect the growth and development of plants, but the interaction between microplastics and heavy metals on plants is less studied. In this study maize seeds were used as the research object to explore the effects of polypropylene microplastics(PP-MPs) and heavy metal cadmium (Cd) on seed germination, seedling growth and oxidative stress of maize with different particle sizes (50 μm and 100 μm). The results showed that the germination rate, germination potential and viability index of PP-MPs+Cd treated seeds were improved, Cd treatment and PP-MPs treatment had inhibitory effects on the mean germination time (MGT), and Cd, 50 μm PP-MPs+Cd and 100 μm PP-MPs+Cd treatments all had certain inhibitory effects on MGT to varying degrees. Cd and 100 μm PP-MPs+Cd treatment inhibited the growth of maize seeding roots and shoots on both the third and the seventh days. On the third day, the fresh weight and dry weight of Cd treatment and 100 μm PP-MPs+Cd treatment decreased by 8.32%, 17.31%, 9.91% and 17.86%, respectively. Overall, PP-MPs+Cd treatment promoted catalase (CAT) and peroxidase (POD) activities in maize roots and shoots, but POD activity decreased by 2.82% at 100 μm PP-MPs+Cd treatment. This study provides a basis for the toxic effects of microplastics and heavy metals on the growth of maize and other crops.

  • Processing and Application
    CHEN Yong, LIU Xu-feng, WEN Shui-ping, CHEN Jian, LIANG Dong, WU Jiao-yu
    Plastics Science and Technology. 2024, 52(08): 77-82. https://doi.org/10.15925/j.cnki.issn1005-3360.2024.08.015

    This article aims to prepare a nitrogen, silicon, and phosphorus multiple synergistic high-efficiency flame retardant and study its application performance. Firstly, allyl substituted melamine was synthesized by melamine powder and allyl bromide. After copolymerizing it with vinyltrimethoxysilane, a nitrogen-silicon containing melamine copolymer was obtained. Using the equal volume impregnation method, a certain mass of Type I ammonium polyphosphate (I-APP) powder is mixed with an equal volume of nitrogen-silicon containing melamine copolymer solution to prepare nitrogen silicon flame retardant copolymer coated I-APP flame retardant (MAPP). Pre mix polypropylene(PP) with a certain mass fraction of I-APP or MAPP flame retardant, and then perform melt blending, extrusion, and granulation in a twin-screw extruder to prepare PP flame retardant composites. Mechanical and vertical combustion tests were conducted on PP flame-retardant composites. The results showed that when MAPP was added up to 20%, it could reach the V-0 flame retardant level, while pure I-APP, even with 30% addition, remained below the V-0 level and had lower mechanical properties. It can be seen that the compatibility of I-APP coated with nitrogen silicon copolymer is better, and the synergistic flame retardant efficiency among nitrogen, silicon, and phosphorus is higher.

  • Theory and Research
    LI Ya-sha, PANG Meng-hao, WANG Jia-min, CHEN Jun-zhang, WANG Lu-min
    Plastics Science and Technology. 2024, 52(08): 7-11. https://doi.org/10.15925/j.cnki.issn1005-3360.2024.08.002

    As a green and recyclable thermoplastic material, polypropylene (PP) has a good application prospect in high voltage cable line. However, its thermodynamic performance is difficult to directly meet the requirements of the cable line, so the PP material needs to be modified to meet the performance requirements. Therefore, based on molecular simulation technology, a nano-CaCO3/PP composite model with doping mass fraction of 3% and 7% nano-CaCO3 and doped grafted silane coupling agent was built, the data of thermal and mechanical properties were calculated, and the changes of its properties were analyzed from a microscopic perspective. The results show that the thermal and mechanical properties of the composites model with grafting number 2 improved the best. In terms of thermal properties, the glass transition temperature (T g) value increased by 49 K, the free volume fraction decreased by 2.52%, and the thermal conductivity was the highest. In terms of mechanical properties, the rigidity decreased the most, and the toughness improved the most.

  • Theory and Research
    WU Tian-yu, BAI Shan, WANG Jun-hao, JIANG Jing-jing, MENG Xiao-yu, YE Hai-mu
    Plastics Science and Technology. 2024, 52(08): 12-17. https://doi.org/10.15925/j.cnki.issn1005-3360.2024.08.003

    Polylactic acid (PLA) is a high-modulus, high-strength biodegradable thermoplastic polyester used in the packaging, textile and medical industries. Conventional plasticizers are usually non-biodegradable, the study used low molecular polyhexanediol succinate (PHS) blended with poly (L-lactic acid) (PLLA) to obtain a fully degradable system. The compatibility, crystallization and mechanical properties of the blended system were investigated by differential scanning calorimetry, polarizing microscope and universal testing machine. The results show that the crystallinity of PLLA/PHS ratios of 100/0, 95/5, 90/10, 85/15, and 80/20 were 7.5%, 8.7%, 11.5%, 14.1%, and 14.2%, respectively. The crystallinity of the blends increased with increasing PHS content, indicating that PHS successfully promoted PLLA crystallization. In addition, the crystallization rate of 80/20 was increased 10-fold and the semi-crystallization time was halved compared to pure PLLA. The elongation at break of the blends increased from less than 10% for pure PLLA to about 60% (PHS content 20%), with a slight decrease in strength and modulus. The elastic modulus of the blends decreased continuously with the increase of the PHS content, from 2.25 GPa for pure PLLA to 1.86 GPa at 20% PHS content.

  • Theory and Research
    SHE Han-wen, ZHONG Jing-jun, GUO Wen-shuai, ZHU Jin-ping, LIU Yang-sen, XU Bai-ping, TAN Ling-cao
    Plastics Science and Technology. 2024, 52(08): 1-6. https://doi.org/10.15925/j.cnki.issn1005-3360.2024.08.001

    Polybutylene adipate-terephthalate/thermoplastic starch/organic montmorillonite (PBAT/TPS/OMMT) biodegradable materials have attracted wide attention in recent years. However, the conventional twin-screw processing technique leads to material degradation and makes it difficult to achieve good stripping of OMMT. In order to improve its mechanical properties, PBAT was chain expansion modified by ADR-4468, and PBAT/TPS/OMMT containing different contents of modified PBAT (A-PBAT) were prepared by melt extrusion using a perturbation ring dual-speed twin-screw extruder, and the effects of different contents of A-PBAT on the microstructure, rheological properties, compatibility, water absorption and mechanical properties of the composites were analyzed. The results showed that the chain extender effectively improved the mechanical properties of PBAT, and the dual-speed twin-screw could strip OMMT well and make TPS uniformly dispersed and distributed in PBAT. With the increase of A-PBAT content, TPS transforms from continuous phase to dispersed phase, the water absorption of the composite material gradually decreases, and the tensile strength gradually increases, reaching its maximum at a mass fraction of 60% A-PBAT, with a slight decrease in elongation at break. 20% A-PBAT can effectively improve the compatibility between TPS and PBAT.

  • Review
    LEI Gao-wei, XU Cong-jie, CAO Shen-ao, YAO Li-min, WU Min, DAI Lu
    Plastics Science and Technology. 2024, 52(08): 144-150. https://doi.org/10.15925/j.cnki.issn1005-3360.2024.08.028

    The article reviews the latest research progress of modified cellulose filled polylactic acid composites, aiming to promote further research and application of this composites. By introducing the application of different modification methods to improve the performance of polylactic acid, such as surface modification of cellulose, functionalization research, grafting copolymerization modification, etc, the performance improvement effect of modified cellulose filled polylactic acid composites was summarized, including mechanical properties, thermal stability, degradation properties, antimicrobial properties, oxygen permeability, UV shielding, crystalline morphology, slow release behavior, etc. Finally, further research in this field was discussed, such as exploring the nucleation mechanism and composite properties of modified cellulose filled polylactic acid, as well as the synergistic mechanism of multiple modification methods and the microstructure of composites. Future research should focus on optimizing modification methods, studying filling mechanisms, and improving the microstructure of composites to achieve better modification effects and performance enhancement. At the same time, further explore more suitable modification methods and composites preparation processes, promote the development of this field and expand its application areas.

  • Review
    HAN Feng, WANG Shuo, WANG Kuan, LI Xiao-ge, FENG San-san, YANG De-liang, CAO Kuan-kuan
    Plastics Science and Technology. 2024, 52(08): 138-143. https://doi.org/10.15925/j.cnki.issn1005-3360.2024.08.027

    Microplastics (MPs), as an emerging pollutant, have attracted widespread attention from scholars both domestically and internationally due to their potential harm to the ecosystems. At present, the presences of MPs have been widely detected in the global water environment, so the removal of MPs in water bodies is particularly important. There is no treatment technology that can completely remove MPs from water presently. This article introduces typical MPs removal technologies from the aspects of methods, influencing factors, and removal results based on existing research, and looks forward to future related research. The physical technology operation process is simple and currently has relatively more practical applications. Chemical technology has a high removal efficiency, but further research and promotion are still needed; Biotechnology is relatively energy-efficient and economical, but it is not yet suitable for promotion and use in practical applications. Future research should focus more on the treatment of small-sized MPs and strengthen the combination of multiple treatment technologies. The article will provide a research foundation and direction for the removal of MPs in water bodies, in order to better solve the problem of MPs pollution.

  • Theory and Research
    LI Lian-rong, ZHENG Xiao-xi, LIU Yong-chao, JIA Guang-hai, BAI Ling
    Plastics Science and Technology. 2024, 52(08): 24-27. https://doi.org/10.15925/j.cnki.issn1005-3360.2024.08.005

    Using styrene maleic anhydride copolymer (SMA) grafted onto silica nanoparticles, polycarbonate/acrylonitrile butadiene styrene copolymer (PC/ABS) blends were prepared by a two-step method, and the effect of SMA copolymer on the coefficient of thermal expansion (CTE) and impact strength of PC/ABS blends was investigated. The results showed that the addition of SMA copolymer resulted in a decrease in the flowability of PC/ABS blends, while their heat resistance was enhanced. Meanwhile, with the increase of SMA content, the CTE of PC/ABS blends decreased to varying degrees compared to S0, among which the CTE of S1, S2, S3 and S4 respectively decreased by 19.8%, 44.5%, 43.1%, and 41.4% compared to S0. The addition of SMA copolymer effectively improved the LOI value of PC/ABS composites, with S2 sample having the highest LOI value of 28.8%, and the UL-94 measurement result was V-0, with no dripping observed. In addition, with the increase of SMA copolymer content, the tensile strength of PC/ABS blends shows a trend of first increasing and then slightly decreasing, the bending strength shows a trend of first increasing and then stabilizing, the elongation at break shows a trend of first decreasing and then stabilizing, and the notch impact strength shows a continuous upward trend. Among them, the S2 sample has the highest tensile strength, bending strength, and high notch impact strength, with values of 41.6 MPa, 102.4 MPa, and 15.3 J/m2, respectively, which are 29.6%, 10.7%, and 1.35 times higher than the corresponding parameters of the S0 sample.

  • Theory and Research
    GE Yun-peng, BAO Rui-yu, XUE Fu-qiang, LIU Yun, LUO Peng, HUI Ya-ni
    Plastics Science and Technology. 2024, 52(08): 45-48. https://doi.org/10.15925/j.cnki.issn1005-3360.2024.08.009

    Silicon carbide whiskers (SiCw) were used as reinforcing fillers in high-density polyethylene (HDPE) to prepare high-density polyethylene/silicon carbide whiskers (HDPE/SiCw) composites. By characterizing and analyzing the thermal conductivity, Vicat softening temperature, thermal and mechanical properties of HDPE/SiCw composites, the influence of SiCw content on the mechanical and thermal conductivity of HDPE composites is explored. The results showed that with the increase of SiCw content, the thermal conductivity of HDPE composites continued to increase, and the melting temperature T m and enthalpy ΔH both continued to increase. The thermal stability of HDPE composites has been effectively improved. At the same time, the Vicat softening temperature of HDPE composites shows a trend of first increasing and then slightly decreasing. The elastic modulus, yield strength, and fracture strength of HDPE composites all show a trend of first increasing and then fluctuating or stable changes, while the elongation at break shows a decreasing trend. When the SiCw content is 30%, the thermal conductivity of HDPE/SiCw composites is 0.85 W/(m·K), the melting temperature T m and enthalpy ΔH were 144.12 ℃ and 162.1 J/g, respectively. The elastic modulus, yield strength, and fracture strength of HDPE composites were 1 301.0, 36.5, 22.4 MPa, respectively, increased by 47.51%, 36.70%, 57.75%, respectively compared with pure HDPE.

  • Theory and Research
    WEI Ju, MA Zheng-lu, HUANG Kun, GAN Qiao
    Plastics Science and Technology. 2024, 52(07): 38-42. https://doi.org/10.15925/j.cnki.issn1005-3360.2024.07.008

    Tough conductive carbon black/nylon66 (CCB/PA66) antistatic composites modified by maleic anhydride-grafted ethylene-vinyl acetate copolymer (EVA-g-MAH) were prepared by twin-screw extrusion and injection molding. The mechanical, melt flow, and antistatic properties of the composites were tested, and the fracture surface morphologies and crystallization behavior of the composites were observed and studied by scanning electron microscopy (SEM) and differential scanning calorimetry (DSC), respectively. The results showed that EVA-g-MAH has good compatibility with PA66. The antistatic properties of PA66 increased with the addition of CCB, however the toughness and processing ability of the composites decreased significantly. The addition of 10% EVA-g-MAH in the 8% CCB/PA66 blend resulted in a 75.4% and 45.1% increase in impact strength and elongation at break, respectively, while maintaining relatively higher tensile strength (50.5 MPa). When the mass fraction of EVA-g-MAH was 20%, the volume resistivity and surface resistance and of 8% CCB/PA66 decreased by 2 to 3 orders of magnitude to 4.3×107 Ω∙cm and 6.5×106 Ω, respectively, due to the selective location of CCB particles in 8% CCB/EVA-g-MAH/PA66. 10% EVA-g-MAH enhanced the crystal formation of PA66 in the 8% CCB/EVA-g-MAH/PA6 composites, however 20% EVA-g-MAH inhibited the crystal formation of PA66.

  • Processing and Application
    JIN Chen, HE Wei
    Plastics Science and Technology. 2024, 52(08): 65-70. https://doi.org/10.15925/j.cnki.issn1005-3360.2024.08.013

    This study utilized glucose as the main raw material to prepare carbon nanospheres (CNs) using a hydrothermal method. Polyvinylpyrrolidone (PVP) was employed to modify the CNs, resulting in PVP grafted CNs (PVP-g-CNs). The structural morphology and functional group changes of the CNs before and after modification were characterized using Fourier transform infrared spectroscopy (FTIR), scanning electron microscopy (SEM), and X-ray diffraction (XRD). Additionally, the dispersibility and adsorption performance of the modified CNs for methylene blue (MB) were tested. The results showed that the modified CNs exhibited an increased size and altered surface structure, while the amorphous crystal structure remained unchanged. PVP-g-CNs demonstrated good dispersibility in water, and adsorption tests revealed that when the PVP addition amount was 0.50 g and the MB solution mass concentration was 30 mg/L, the maximum adsorption capacity of PVP-g-CNs for MB reached 155.03 mg/g, with the adsorption capacity increasing with the pH of the solution. The fitting results of the adsorption model showed conformity to the pseudo-second-order kinetic model and the Langmuir model, with a theoretical maximum adsorption capacity of 238.095 2 mg/g, thus demonstrating excellent adsorption performance.

  • Theory and Research
    ZHOU Huang-wei, LI Meng-jue, CAO Jian-fei, CHEN De-ping
    Plastics Science and Technology. 2024, 52(07): 47-51. https://doi.org/10.15925/j.cnki.issn1005-3360.2024.07.010

    The composite electrolyte membranes were fabricated using sulfonated polyether ether ketone (SPEEK) as the precursor material and supercritical carbon dioxide extraction technology, resulting in enhanced ionic conductivity, water absorption, and low methanol permeability. The water absorption of polyether ether ketone (PEEK) electrolyte membranes was enhanced by the sulfonation process, attributed to the formation of efficient ion pathways. The results showed that the ion exchange capacity(IEC) value of the SPEEK electrolyte membrane increased to 1.38 meq/g as the sulfonation time was extended from 3 h to 12 h, concurrently resulting in an increase in the degree of sulfonation to 46%. After sulfonation, the decomposition temperature of the electrolyte membrane decreased, reaching a lower value of 420 ℃. As the sulfonation time increased, the ionic conductivity exhibited an increase from 1.37×10-10 S/cm to 1.16×10-4 S/cm, meanwhile the methanol diffusion coefficient demonstrated a decrease to 2.183×10-7 cm2/s. The study indicates that using sulfonation and supercritical carbon dioxide fluid extraction processes can prepare SPEEK electrolyte membrane with high ionic conductivity and low methanol permeability.

  • Theory and Research
    MA Ke-ming, YANG Hong-jian, LI Chen-xi, ZHENG Shuang, REN Jian-nan
    Plastics Science and Technology. 2024, 52(07): 18-22. https://doi.org/10.15925/j.cnki.issn1005-3360.2024.07.004

    A lightweight and high-strength water-soluble core mold for composites was prepared by hot-air drying method using aqueous solution of polyvinylpyrrolidone as the adhesive and hollow glass beads, gypsum and graphite as the matrix materials. The effects of adhesive content and matrix material on the mechanical properties and dissolution rates of the water-soluble core mold were investigated. The effect of modification methods on the mechanical properties of water-soluble core molds was investigated, and the microscopic morphology of the modified water-soluble core mold was observed by scanning electron microscopy (SEM), and its modification mechanism was initially explored. The results shows that the density of water-soluble core mold is 0.46~0.58 g/cm3, and the high-temperature treatment and the compounding of glass beads with different scales of particle size are the effective means of modification. The flexural strength of the water-soluble core can reach 7.46 MPa, the compression strength reaches 7.45 MPa, and the dissolution rate is 1.11 g/min before the modification, while the flexural strength of the modified core mold can reach 13.21 MPa, the compression strength reaches 13.45 MPa, and the dissolution rate is 6.34 g/min. The comprehensive performance of the water-soluble core mold can meet the requirements of the composite molding process, and it provides a solution for the integrated molding of the hollow profiled composites.

  • Theory and Research
    YANG Xing-cheng, WANG Yi, CHEN Jie
    Plastics Science and Technology. 2024, 52(07): 33-37. https://doi.org/10.15925/j.cnki.issn1005-3360.2024.07.007

    POE was used to modify polypropylene (PP) to improve paint adhesion on the surface of PP material for automotive interior. By means of differential scanning calorimetry, scanning electron microscope, Dyne pen, Paints Cross-cut test and mechanical property test, the effects of POE on crystallization property, dispersion ability, surface tension, paint adhesion and mechanical properties of modified PP were investigated. The results show that with the increase of POE, the tensile yield strength and bending modulus of modified PP decrease, and the notch impact strength increases. The higher melt flow rate (MFR) of POE, the greater the reduction of rigidity. The higher the content of POE, the more favorable it is to improve the surface adhesion of modified PP. When the POE content is not less than 15%, the Paints Cross-cut test level of the template reaches 0. The higher the MFR of POE, the more conducive to the orientation and dispersion of the rubber phase on the surface of the template, which is conducive to the immersion of the paint and the improvement of the paint adhesion. When the paint film thickness is less than 26 μm, it is difficult to form an effective and dense paint film on the surface of the template, resulting in poor paint adhesion of the template. When the paint film thickness is not less than 26 μm, the template paint adhesion is better.

  • Processing and Application
    ZHENG Yong-juan
    Plastics Science and Technology. 2024, 52(07): 105-108. https://doi.org/10.15925/j.cnki.issn1005-3360.2024.07.023

    The effects of single and compound fly ash and plastic waste on the mechanics and durability of concrete modified with fly ash and polypropylene particles are studied. The results show that the appropriate amount of fly ash has no obvious effect on the mechanical properties of concrete at late age, and the appropriate amount of fly ash can improve the durability of concrete at late age. Single-doped polypropylene plastic particles reduce the mechanical properties and durability of concrete. The mechanical properties and durability of concrete in the late stage can be effectively improved by adding fly ash and polypropylene particles in appropriate amount. When the mass ratio of fly ash and polypropylene particles is 1∶1, the mechanical properties and durability of concrete are better under the condition that the total content is 30%.

  • Theory and Research
    QIN Fei-fei, SHENG Dong-fa
    Plastics Science and Technology. 2024, 52(07): 12-17. https://doi.org/10.15925/j.cnki.issn1005-3360.2024.07.003

    Based on the integral equations of internal strain fields in elastic bodies containing inclusions, the deformation coordination tensor of inclusions in three-phase composites is derived. Compared with the traditional Mori-Tanaka method (M-T method), the deformation coordination tensor takes into account the distribution characteristics and interactions of inclusions from the perspective of micromechanics, leading to a modified M-T method for predicting the effective elastic properties of composites. Combining with the two-step homogenization model, a method for predicting the effective performance of hybrid fiber composites is derived. Additionally, a prediction model for the tensile strength of hybrid fiber composites is established based on the damage mechanics theory. This method is used to predict the effective elastic properties and tensile strength for coconut husk fiber/glass fiber reinforced phenolic resin composites reported in the literature, and compared the predicted results with experimental data. The results show that the proposed modified M-T method has better predictive ability than the traditional M-T method, with the predicted results and experimental data differing by less than 10.485%. The method is used to quantitatively analyze the effect of the content of coconut husk fiber and glass fiber on the effective elastic properties and tensile strength of hybrid fiber composites. The results show that the effective elastic properties and tensile strength of hybrid fiber composites increase with the increase of glass fiber content.

  • Biological and Degradable Material
    WU Jing, HUANG Jia-yuan, LAN Jun-feng, CHEN Yan-meng, YE You-ming, WEI Zhou-qiao
    Plastics Science and Technology. 2024, 52(07): 121-124. https://doi.org/10.15925/j.cnki.issn1005-3360.2024.07.026

    In this study, polyethylene (PE) was used as the raw material, and polyhydroxyalkanoate (PHA), modified nano-CaCO3 and bagasse fiber(BF) were used as the composite fillers, and the nano-CaCO3/BF/PHA/PE composites were prepared by melt extrusion and injection molding. The effects of the optimal ratios of PHA, modified nano-CaCO3 and BF and their contents on the internal structure and properties of the composites were investigated by mechanical property tests, Fourier transform infrared spectroscopy (FTIR) analysis, thermogravimetric (TG) analysis, scanning electron microscopy (SEM) and other characterization methods. The results show that with 5% PHA, 5% BF, and 5% nano-CaCO3, the mechanical properties of the composites were optimal at 12.9 MPa, and the maximum thermal decomposition temperature of the nano-CaCO3/BF/PHA/PE composites reached 437 ℃ at this ratio, which was higher than the thermal decomposition temperature (453 ℃) of the composites before modification. The study provides ideas for the green development of degradable polymer materials.

  • Theory and Research
    QI Yi-xin, JU Su
    Plastics Science and Technology. 2024, 52(07): 1-6. https://doi.org/10.15925/j.cnki.issn1005-3360.2024.07.001

    In order to study the differences of structure, orientation and energy changes during the interfacial formation of single-walled carbon nanotube/crystalline and amorphous thermoplastic resin composites, built the bridge between microstructure and macroscopic properties, molecular models of single-walled carbon nanotubes/polypropylene (SWCNT/PP), single-walled carbon nanotubes/polyethylene (SWCNT/PE) crystalline, single-walled carbon nanotubes/polystyrene (SWCNT/PS), single-walled carbon nanotubes/polymethyl methacrylate(SWCNT/PMMA) amorphous thermoplastic resin composite systems were established by molecular dynamics simulation. The forming process of the interphase was simulated, radial distribution function, interface energy and total energy were calculated. The simulation results showed that the formation process of the interphase of the SWCNT/PS and SWCNT/PMMA were mainly adsorption. While the formation process of the interphase of the SWCNT/PP and SWCNT/PE were divided into adsorption and orientation. The g(r) of the SWCNT/PP and SWCNT/PE firstly decreased sharply in the range of r, then the value of the g(r) increased sharply, therefore the interphase crystallized, forming a short-range ordered structure. At 2 000 ps, the interfacial energy of the SWCNT/PP and SWCNT/PE were -620.1 kcal/mol and -791.7 kcal/mol, which were smaller than that of the SWCNT/PS and SWCNT/PMMA, so the interface bonding were better. The total energy of the SWCNT/PP and SWCNT/PE decreased gradually, which were -1 654.9 kcal/mol and -1 211.2 kcal/mol at 2 000 ps. Compared to the SWCNT/PS and SWCNT/PMMA, the total energy of the SWCNT/PP and SWCNT/PE were smaller, and the composite system were more stable.

  • Theory and Research
    SUN Xiao-jie, REN Yue-qing, CHEN Lan-lan
    Plastics Science and Technology. 2024, 52(07): 23-27. https://doi.org/10.15925/j.cnki.issn1005-3360.2024.07.005

    Crosslinking modification is one of the important methods of polyethylene modification. The effects of crosslinking degree and resin structure on rheological properties, crosslinking properties, crystallization properties and mechanical properties of crosslinked high density polyethylene (XHDPE) were studied. The results show that when the mass fraction of crosslinking agent increases from 0 to 1.2%, the maximum energy storage modulus (G'max) and gel content of XHDPE increase, and the minimum value of loss factor (tanδ min) decreases gradually. With the increase of the content of crosslinking agent, the crystallinity and grain size of XHDPE decreases, and the crystallization capacity decreases. After the addition of crosslinking agent, the tensile yield strength of XHDPE decreases gradually, the elongation at break increases first and then decreases, and the impact strength increases significantly. With the same content of crosslinking agent, the energy storage modulus of XHDPE and the viscoelasticity of macromolecular network increase gradually with the increase of molecular weight of base resin. When the elongation at break of high molecular weight HDPE reaches the maximum, the content of crosslinking agent required is lower. High molecular weight HDPE base resin is beneficial to improve the mechanical properties of crosslinked samples.

  • Processing and Application
    WANG Shuang, LIU Xiang-yu, QI Hong-gang
    Plastics Science and Technology. 2024, 52(07): 84-87. https://doi.org/10.15925/j.cnki.issn1005-3360.2024.07.018

    In order to improve the application performance of chromium-based single-peak high density polyethylene(HDPE) special material HD5502S for small-sized hollow containers, it was extruded and granulated according to the different blending mass ratio with HDPE DGDA6098 for film with good toughness. The physical, mechanical and rheological properties of the mixture were analyzed and compared. The results showed that the processing performance of the mixtures was better when the blending mass ratio of DGDA6098 was less than 40%. When the blending mass ratio of HD5502S/DGDA6098 was in the range of 90/10~70/30, the bending modulus of the mixtures was higher than 1 400 MPa, and the impact strength was also higher than 13 kJ/m2, which had a good rigidity and toughness balance. At different temperatures, with the increase of the blending mass ratio of DGDA6098, the shear viscosity (η) and shear stress(τ) of the blends increased, and the critical shear rate (γc ) decreased. When the processing temperature was 190 ℃, the rheological properties of HDPE mixtures for small-sized hollow containers were the best. The appropriate blending mass ratio was conducive to the formation of a physical bimodal distribution, and the comprehensive performance of the HD5502S mixtures were the best when the blending mass ratio of HD5502S/DGDA6098 was 70/30 and the processing temperature was 190 ℃.

  • Biological and Degradable Material
    LIU Zhi-gang, BIAN Jun-jia, HUAN Yue-wei, LI Jun-wen, SUN Li-na, ZHOU Wei-hua, YAN Xiang-yu
    Plastics Science and Technology. 2024, 52(07): 115-120. https://doi.org/10.15925/j.cnki.issn1005-3360.2024.07.025

    The study was to improve the heat resistance of polylactic acid (PLA) through blending modification. Ethylene-methyl acrylate-glycidyl methacrylate (E-MA-GMA) and poly(butylene succinate) (PBS) and talc powder (talc) were added to PLA matric to prepare PLA/E-MA-GMA/PBS/talc blends. The effects of PLA/E-MA GMA/PBS/talc content on the mechanical properties, flowability, rheological properties, heat resistance of the blends were studied. The results show that with the change of PLA/EMAGMA/PBS/ talc blend system, the tensile strength of the blends gradually decreases, while the toughness and impact strength gradually increase, indicating the existence of partial toughening and compatibility between the blend materials. Theheat deflection temperature of the untreated blends remains relatively stable at around 55 ℃, while the heat deflection temperature of the crystallized blends is generally higher than 90 ℃.

  • Additives
    LI Chun-hui, HAO Chun-bo, YAO Xiu-chao, ZHAI Xu-peng, ZHUANG Song, YU Hong-yang, LIU Quan-zhong
    Plastics Science and Technology. 2024, 52(07): 131-134. https://doi.org/10.15925/j.cnki.issn1005-3360.2024.07.028

    In this paper, the effects of four different types of nucleating agents, namely, α-nucleating agent CH-6N, HPN-715, TMP-7 and β-nucleating agent TMB-5, as well as the effects of compounding of different types of nucleating agents on the mechanical, optical and crystalline properties of polypropylene were investigated. The results show that the nucleating agent can effectively increase the crystallization temperature and crystallinity. α-nucleating agent CH-6N has the best rigidity effect. The bending modulus and bending strength of polypropylene are 2 390 MPa and 60.6 MPa respectively with the addition of 0.2% CH-6N. The α nucleating agent can reduce the toughness of polypropylene. Adding 0.2% CH-6N, the impact strength of polypropylene is only 2.7 kJ/m2. The β-nucleating agent TMB-5 can effectively improve the toughness of polypropylene, but reduce the rigidity. The toughening effect of 0.1 % TMB-5 is the best. The impact strength of polypropylene is 20.7 kJ/m2, and the elongation at break is 530%. In terms of optical properties, α nucleating agent CH-6N has the best modification effect, and after the addition of 0.1% CH-6N, the yellow index of polypropylene is only 0.46. The combination of α nucleating agent and β nucleating agent can not only improve the toughness of polypropylene, but also improve its rigidity, and achieve the balance of rigidity-toughness. The compound modification effect of 0.1% CH-6N and 0.1% TMB-5 is good, and the impact strength of polypropylene is 5.5 kJ/m2, the bending modulus is 2 140 MPa, and the tensile strength is 41.1 MPa.

  • Plastic Machinery and Mold
    DING Ligang, CHENG Guofei, CHEN Xianxuan, HUANG Chujie, LIN Xu
    Plastics Science and Technology. 2025, 53(01): 147-151. https://doi.org/10.15925/j.cnki.issn1005-3360.2025.01.027

    Based on the analysis of the structure characteristics and material properties of the fixing seat of automobile rearview mirror, the structure scheme and design key points of the injection mould were worked out. Then, an injection mould with two cavities and angle ejector of the front mould was designed. A gating system that combines hot runners with conventional runners, insert-molded forming components, and precise positioning mechanisms were designed to ensure that the mold cavity can be filled and formed smoothly and achieve accurate positioning. A lateral core-pulling mechanism with the combination of the angle pin core-pulling and the angle ejector core-pulling, and the compound push-out mechanism with the combination of the push rod and the push pipe were designed to ensure the smooth core-pulling and demoulding of the plastic parts. In addition, a three-dimensional cooling circuit was designed to shorten the molding cycle of plastic parts. The results show that the mold structure is reasonable and the action is reliable, which can provide a reference for the design of the same type of injection mold.

  • Computer Aided Technology
    ZHANG Shouhui, MENG Fantao
    Plastics Science and Technology. 2025, 53(01): 142-146. https://doi.org/10.15925/j.cnki.issn1005-3360.2025.01.026

    Combined with the experimental data from previous study, a bilinear isotropic hardening model of glass fiber reinforced polyamide 6 (PA6/GF) composites was established, and the effect of glass fiber (GF) content on the mechanical properties of the composites was studied, which can provide a reference for the simulation analysis and experimental design of PA6/GF composites. Firstly, based on the finite element analysis of Ansys, the element model of PA6/GF composites was established from a microscopic perspective, and the results showed that the composites had isotropic characteristics. Then, the bilinear isotropic hardening model was used to simulate and analyze the bending performance and yield performance of the splines, and the results showed that the bending strength was basically consistent with the experimental data, and the yield strain was smaller than the engineering strain, which was in line with the theoretical law. Finally, the effect of GF content on the mechanical properties of PA6/GF composites was studied through the simulation results. The results showed that with the increase of GF content, the tensile strength of the composites gradually increased, when the GF mass fraction reached 40%, the tensile strength reached 207.5 MPa, which was about three times that of pure PA6, and the impact strength of the composites increased first and then decreased with the increase of GF content, and when the GF mass fraction was 35%, the impact strength of the composites reached 21.6 kJ/m².

  • Theory and Research
    ZHANG Kefeng, LI Lu, DUAN Jiaqi, LIANG Jingyuan, YANG Mengjiao
    Plastics Science and Technology. 2025, 53(01): 68-75. https://doi.org/10.15925/j.cnki.issn1005-3360.2025.01.012

    To clarify the curing mechanism of hyperbranched polymer modified carbon nanotubes/epoxy resin composite materials and the influence mechanism of different hyperbranched polymers on the curing behavior of epoxy resin matrix, a moving window two-dimensional correlation infrared analysis method was used, and a comparative analysis was conducted on the changes in characteristic functional groups of hyperbranched polyester modified carbon nanotubes/epoxy resin composite material (EP/MWCNTs H204) and hyperbranched polyamide modified carbon nanotubes/epoxy resin composite material (EP/MWCNTs N103) during the heating and curing process. The sequence of changes in each functional group was discussed in detail using generalized two-dimensional correlated infrared analysis. The influence of the introduction of different hyperbranched polymers on the curing behavior of epoxy resin composites was reasonably explained.