Materials and Properties
2025, 39 (1):
1-5;
Abstract (
221 )
PDF (0 KB)(
11
)
Commercial trial on HDPE unit of 350 kt·a-1 Hostalen ACP process for producing ACP7000F film grade resin by BCE-H200 catalyst had been succeeded. Using melt flow rate (MFR), gel permeability chromatography (GPC) and mechanical tests to characterise general performance of catalyst, polyethylene (PE) powder and film resin. Tests result showed that BCE-H200 catalyst had higher activity, stabler hydrogen response and excellent copolymerisation ability. Compared to reference catalyst, the activity of BCE-H200 catalyst improved 87.5%, hydrogen consumption decreased 12.5%, butene-1 consumption decreased 13.1%, fines were less, and average particle size of its PE powder was bigger. Mechanical properties of film resin produced by BCE-H200 catalyst was better, less gel under high load, which met production standard of customer. Imported catalyst can be replaced by BCE-H200 catalyst for producing high performance film grade resin. Researching on gel from reference film showed that its content was PE of high molecular weight and low crystallinity.
CHEN Mingguang, LI Mengdi, YU Chen, CAO Hongzhang, YU Xiaoli, LIU Zhaogang, LUO Guoping
Abstract (
76 )
PDF (2182 KB)(
57
)
HTML (
1 )
A rare earth compound, fumaric acid pentaerythritol lanthanum (FGPE⁃La), was synthesized using fumaric acid, pentaerythritol, and lanthanum acetate as raw materials. The chemical structure and composition of the resultant FGPE⁃La were characterized, and its thermal stability and antibacterial properties when used in PVC were investigated. The results indicated that FGPE⁃La could be used as a multifunctional PVC additive with both good thermal stability and antibacterial properties. When a mixer of FGPE⁃La and ZnSt2 at a mass ratio of 3:1 was used for PVC, good initial whiteness and long⁃term thermal stability could be obtained in the modified PVC. Moreover, the thermal stability time of the modified PVC reaches 68 minutes when 4 phr FGPE⁃La was incorporated alone, indicating a significant improvement in the long⁃term stability. An antibacterial rate of 99.1 % was achieved for the modified PVC containing 6 wt.% FGPE⁃La, and its hemolysis rate was only 4.6 %, indicating good biocompatibility.
XU Qiangxiang, ZHANG Guoping, HU Yihong, YANG Fayong, ZHAO Qiongyang, LI Zhigang
Abstract (
79 )
PDF (1140 KB)(
41
)
HTML (
0 )
Aiming to address the phenomenon of high prices of commonly used styrene⁃butadiene⁃styrene (SBS)⁃modified asphalt at present, this work focuses on a reduction in the engineering cost of SBS⁃modified asphalt. The basic performance, storage stability, anti⁃aging performance of the desulfurization crumb rubber (DCR)/SBS⁃modified asphalt was studied with the purpose of improving the asphalt performance and enhancing the effective recycling of waste crumb rubber. Scanning electron microscopy and the Fourier⁃transform infrared spectroscopy were conducted to analyze and evaluate the morphological characteristics and chemical properties of the modified asphalt. The results indicated that the addition of SBS and desulfurized crumb rubber improved the high⁃ and low⁃temperature performance, storage stability, and anti⁃aging performance of the modified. The desulfurized crumb rubber and SBS as modifiers were uniformly dispersed in the asphalt matrix and crosslinked with each other. The interface at the desulfurized crumb rubber⁃SBS⁃asphalt three phases was fuzzy. Desulfurized crumb rubber and SBS were coexisting in asphalt through the physical modification and chemical reaction. This study provides a technical reference for further popularization and application by using waste crumb rubber to partly replace the SBS modifier in the road project.
HUANG Qizhong
Abstract (
88 )
PDF (1978 KB)(
47
)
HTML (
2 )
The effect of two types of phosphate ester hydroxyaluminum salt nucleating agents, NA⁃21 and TD⁃531, on the crystallization process of coal⁃based impact⁃resistant copolymerization⁃type polypropylene (PP) was investigated, realizing the regulation of the mechanical properties of the PP. The results indicated that both of the nucleating agents could act as α⁃Type nucleating agents for the PP to significantly increase its crystallization peak temperature and nucleation density, thus accelerating the overall crystallization rate of the PP and improving its rigidity and processing efficiency. TD⁃531 generated a more significant effect on improving the performance of the PP in contrast to NA⁃21. When the addition amount of TD⁃531 was only 0.075 %, the crystallization peak temperature of the PP increased to 131.8 ℃, its semi⁃crystallization time decreased to 0.35 min. Compared to those of pure PP, the crystallization peak temperature increase by 10 ℃ and the semi⁃crystallization time decreased by 5.48 min. Meanwhile, the flexural modulus and impact strength of the PP increased to 1 377 MPa and 68.9 kJ/m2, respectively, which were increased by 330 MPa and 22.3 kJ/m2, respectively, compared to those of pure PP. This demonstrated a good balance between the rigidity and toughness thanks to a good dispersion effectiveness of the nucleating agent.
2025, 39 (1):
25-30;
Abstract (
28 )
PDF (0 KB)(
11
)
In order to improve the dielectric and mechanical properties of silicone rubber, zero-dimensional onion-like carbons (OLCs) and two-dimensional boron nitride nanoplates (BN) were added to the silicone rubber (SR) to prepare OLCs/BN/SR composites. Through systematic study of the prepared composites, it is found that the fillers can be uniformly dispersed in the polymer matrix, and the dielectric and mechanical properties of OLCs/BN/SR composites were obviously enhanced. When 1.2 wt% OLCs and 9 wt% BN nanoplates were added to the SR, the dielectric constant of the composite increased to 7.31, while the dielectric loss was as low as 0.00152. This is mainly because the coordination effect between the different fillers improves the dispersion of the fillers in the polymer matrix and enhances the interfacial polarization effect in the composites. The composites also showed good flexibility, i.e. the elongation at break was 748% and the elastic modulus was 227 kPa. Therefore, the coordination between low dimensional fillers of different dimensions can make the composites exhibit high dielectric constant, low dielectric loss and low elastic modulus.
HE Wenfeng, ZHAO Tongjie, XIE Yuhui, MEI Yi, XIE Delong
Abstract (
88 )
PDF (1073 KB)(
39
)
HTML (
2 )
Silicone resin is a type of high⁃temperature⁃resistant material with excellent properties and exhibit broad application prospects in the field of heat resistance. With a rapid development of silicone resin for thermal protection coating in the national defense industry, it is difficult to meet the current requirement of applications. Therefore, there is a great strategic value to improve the high temperature resistance of silicone resin. Thermally stable vinyl silicone resin containing hydrogen was successfully prepared by a simple two⁃step method under acidic conditions using the alkoxysilanes containing silicon⁃hydrogen and silicon⁃ethylene bonds as raw materials. The synthesis conditions of the modified silicone resin were investigated by infrared spectroscopy and thermogravimetry analysis, and its chemical structure, thermal stability, and thermal decomposition mechanism by thermogravimetric Fourier transform infrared analysis. The results indicated that the synthesis conditions were determined to be a pH of 1.0, a hydrolysis temperature of 30 ℃, and a hydrolysis time of 3 h by using triethoxysilane and vinyl triethoxysilane as monomers and ethanol and hydrochloric acid as organic solvents. The as⁃synthesized silicone resin obtained a char yield of 97.84 % at 800 ℃ when synthesized under the optimum conditions, and its high temperature resistance was far higher than that of the ordinary silicone resin. The thermal decomposition of the hydrogen⁃containing vinyl silicone resin included two stages: the first stage occurred at about 253 ºC due to the oxidative degradation of partial vinyl of side⁃linked branches of silicone resin; The second stage taking place at 578 ºC, which was caused by the random fracture and rearrangement of SR skeletons due to the back reaction of silicone hydroxyl end groups of silicone resin.
GAO Ting, PENG Qiang, MA Xiuqing
Abstract (
99 )
PDF (603 KB)(
268
)
HTML (
0 )
Polycarbonate (PC) is a type of engineering thermoplastic with excellent comprehensive properties. In order to expand its application range, toughening modification is necessary to improve the toughness of PC. This paper reviewed the latest research progress in the toughening modification of PC, and its toughening modification methods were classified and summarized. These methods mainly included toughening modification using elastomers, inorganic rigid particles, and organic rigid particles. The application prospect of PC and its modified products in the fields of automobiles, building materials and aerospace was analyzed, and its development prospect in toughening and modification was also discussed.
Processing and Application
HU Kunming, WANG Di, JIN Biao, RUAN Jianbo, LIU Wanqiang, XIE Pengcheng
Abstract (
76 )
PDF (1306 KB)(
55
)
HTML (
1 )
Taking the microelectronic components based on a thermotropic liquid crystal polymer (TLCP) as a research object, the Moldflow analysis software was employed to simulate the injection molding process of the microelectronic components. The effect of different core structures on the injection molding of microelectronic components was compared, and the molding efficiency and molding quality of the microelectronic components in the injection molding process were analyzed. Through comparing the three⁃contact and two⁃contact inlay core structures, the optimal injection molding scheme was determined to be the two⁃contact inlay core structure. The two⁃contact inlay core structure had a filling time of 0.020 4 s, an ejection time of 0.123 5 s, an average volumetric shrinkage rate of 4.414 %, and a comprehensive warpage deformation of 0.011 5 mm. These were determined to be the optimal injection molding scheme for the microelectronic components. The average volume shrinkage and integrated warpage deformation were reduced by 0.149 % and 0.002 7 mm, respectively. Although the two⁃contact inlay core structure showed poorer uniformity in fiber distribution than the three⁃contact one, its volume shrinkage and warpage deformation were reduced due to the concentrated fiber distribution at the edge of the inner core. A comprehensive analysis indicated that the two⁃contact inlay core structure was the optimal scheme for the injection molding of microelectronic components.
GAO Dongming, WEI Dandan, WAN Qihao
Abstract (
75 )
PDF (1230 KB)(
110
)
HTML (
0 )
The current standards are difficult to measure the characteristics of silage polyethylene (PE) film under actual working conditions. In this study, uniaxial tensile tests at different tensile rates with a strain range within 200 % and stress relaxation tests at different initial elongations were conducted on the PE film specimens in the machine direction (MD) and transverse direction (TD). The tensile test results indicated that there was a pronounced dependency on both stretching speed and direction in the stress⁃strain (σ⁃ε) profiles, and the films exhibited a secondary yielding phenomenon in both MD and TD orientations. With an increase in the tensile rate, there was a decrease observed in the elongation at the second yield. The first and second yield strengths in the MD direction showed a good linear mapping relationship with the logarithm of tensile rate (ln v). An increase in the tensile rate could improve the yield strength of the PE film. However, the yield strength reduced the toughness of PE film after reaching a certain rate. Stress relaxation tests indicated that both the MD⁃ and TD⁃oriented films presented a rapid decrease followed by a gradual reduction in stress across a range from a low initial stretch level (10 %) to the high one (70 %). The generalized seven⁃element Maxwell model could accurately describe the stress relaxation behavior of the PE film, which offered insights into its long⁃term stress relaxation characteristics. The quantity of stress relaxation and rate of stress decay decreased with an increase in the stretch level. This indicated a reduction in the relaxation modulus as well as a more stable modulus during the slow stress decline phase. These findings suggest that to realize the optimal silage sealing, the PE films should balance stiffness with resilience to relaxation with an ideal stretch range of 50~70 % during wrapping.
PING Yiheng, LI Chen
Abstract (
71 )
PDF (980 KB)(
73
)
HTML (
3 )
Aiming to systematically evaluate the environmental impact of vacuum blister molding for the manufacturing of PET blister trays, a 1⁃t polyethylene terephterate (PET) blister tray was selected as a functional unit. Based on an assessment method for the whole life cycle (LCA) and the environmental impact index of climate change (GWP) as a research focus, a carbon emission calculation model was established for the vacuum blister PET tray on the eFootprint system. The material consumption, energy consumption, and environmental impact evaluation indexes of the production process were quantitatively analyzed by the LCA calculation. The results indicated that in the entire production process of PET blister trays, the treatment of non⁃methane total hydrocarbon and PET sheet extrusion were the key issues with a higher cumulative contribution to carbon emissions, accounting for 47.67 % and 30.22 % respectively. Electricity is the key AP with a higher cumulative contribution to carbon emissions, accounting for 22.80 %. Through capturing the carbon footprint of the whole life cycle of the vacuum blister PET tray, the direction of future emission reduction of this production process was given. According to the concept of energy saving and emission reduction, the two key contributing factors in the process of vacuum blister molding were improved.
JI Jiajun, ZHANG Zengping, LI Junhui, SHI En, LI Qingxu
Abstract (
69 )
PDF (2548 KB)(
94
)
HTML (
0 )
This paper summarized the research progress of epoxy resin materials used as road sealants, introduced the constituent materials and preparation processes of road epoxy resin sealants, analyzed the performance research and modification mechanism of road epoxy resin sealants, and investigated the application of epoxy resin sealants in the field of highway engineering. Finally, the existing problems and deficiencies in the research and application of epoxy resin sealant for road were put forward, and the development prospect was prospected, so as to provide the basis for the further research and promotion of epoxy resin sealant.
Additive
LI Rongnan, YIN Maoli, LIU Feng, HU Chenggong, XING Jian
Abstract (
73 )
PDF (1006 KB)(
40
)
HTML (
0 )
An organic⁃inorganic compound antioxidant (GO⁃sHP) was prepared through chemical grafting of GA⁃80 into graphite oxide (GO) sheets. The resultant GO⁃sHP was melt⁃blended with polyphenylene sulfide (PPS) by using a micro⁃twin⁃screw extruder. The structure and properties of the obtained PPS blends were intensively analyzed. The results indicate that GO⁃sHP showed high thermal stability and could well be melt⁃blended with PPS. GO⁃sHP exhibited good compatibility with the PPS matrix and could be uniformly dispersed in the matrix without any agglomerations. The introduction of GO⁃sHP could promote the crystallization of PPS to improve its crystallinity. As the GO⁃sHP content increased, the crystallization temperature of PPS increased and its supercooling degree decreased. The introduction of GO⁃sHP improved the thermal stability of PPS, and its heat resistance temperature index increased with an increase in the GO⁃sHP content. The addition of GA⁃80 improved the tensile fracture strength of PPS significantly. After thermal oxidation treatment, pure PPS presented a decrease in the tensile fracture strength by 4.1 %. However, the PPS blend containing 0.3 wt% GO⁃sHP showed a decrease in the tensile fracture strength only by 2.4 %.
Standard and Test
YE Linquan, QIAN Taotao, LI Rongbing, ZENG Le
Abstract (
84 )
PDF (806 KB)(
37
)
HTML (
1 )
In this study, a gas chromatographic method was established for the determination of the contents of terephthalic acid (IPA), ethylene glycol (EG) and diethylene glycol (DEG) in polyethylene terephthalate (PET) bottle slices. The optimized and validated method was employed to test the contents of IPA, EG, and DEG in drinking water bottles after. The results indicated that the DEG contents in 16 types of drinking water bottles from 11 different brands was in the range from 1.15 % to 1.44 % with a mean of 1.30 % and a RSD of 7.5 %. The contents of EG are distributed between 30.28% and 32.67 % along with a mean of 32.0 % and a RSD of 2.0 %. The proportion of DEG to EG means was around 4 %. The content of IPA showed a relatively large difference ranging from 0.68 % to 2.3 % along with a common value of 2.03 %±0.35 %.
Plastic and Environment
GAO Chengtao, XU Qiu, ZHANG Li, LI Jian, HUANG Wei, CHEN Jinsong, LIU Nan, HE Shengbao, CHEN Siyao, PAN Shouhui
Abstract (
105 )
PDF (1024 KB)(
210
)
HTML (
1 )
Inorganic nanoparticles have attracted extensive attention in many application fields due to their unique optical, electrical and thermal properties, low toxicity, low cost, good environmental friendliness, and high biological stability. In view of these excellent properties and broad application prospects of biodegradable composites prepared through filling inorganic nanoparticles, this paper reviews the research progress in the application of inorganic metal and inorganic non⁃metal inorganic nanoparticles in biodegradable composites, clarified the mechanism of their action in biodegradable composites, and proposed the key research directions in the future.
ZHOU Tianyu, LI Jiuchong, ZHANG Jingfan
Abstract (
76 )
PDF (653 KB)(
35
)
HTML (
0 )
Two component alcoholysis agents, ethylene glycol (EG) and diethylene glycol (DEG), were used to degrade the waste polyisocyanurate foams (PIR) to obtain polyol as the degradation product. The regenerated PIR foams were obtained through foaming the degradation product. The infrared spectrum and viscosity of the degradation product were and analyzed. The apparent density, compression strength, thermal conductivity and thermal stability of the regenerated PIR were investigated. The results indicated that the degradation of waste PIR and regeneration of PIR obtained an optimal effect at a mass ratio of mEG to mDEG of 1/2 and a NaOH catalyst amount of 1.0 g under the degradation reaction condition at 180 ºC for 1 h and then at 190 ºC for 1 h. In this case, the viscosity of the degradation product was 2 246 mPa∙s. The apparent density of regenerated PIR was 0.044 8 g/cm³, its compressive strength was 0.398 MPa, and its thermal conductivity was 0.025 W/m∙K. All performance parameters can meet a requirement of national standards.
CHEN Zhuo, HU Jie, MA Chao, LI Xiaohui, BAN Tiantian, LIU Xiaocui
Abstract (
65 )
PDF (2576 KB)(
66
)
HTML (
0 )
To explore the application effect on the biodegradable mulch films in vegetable cultivation, the breeding in greenhouse and cultivation in field were carried out by using Chinese cabbage was used as an experimental material. Taking an ordinary PE mulch film as a control, 5 different types of biodegradable mulch films with different thickness and different landfill materials were measured, and a total of 5 treatments were conducted to investigate the effect of biodegradable mulch films on the yield, soil environment, and economic benefits of the cabbage. The results indicated that the soil moisture content, PH value, cation exchange capacity, soil organic matter, soil total phosphorus, available phosphorus and available potassium contents of the degradable film treatment were higher than those of the ordinary one; however, their total salt content and bulk density were lower than those of the ordinary one. In terms of soil effects, the contents of most soil physical and chemical properties under the biodegradable plastic film treatment were higher than those under the ordinary PE plastic film treatment. In terms of the effect on the yield of Chinese cabbage, the biodegradable and ordinary PE films with the same thickness exhibited the same effect on the yield of Chinese cabbage. In terms of the benefits, the ratio of the profit and yield to investment of the cabbage growing under biodegradable mulch films were higher than that of the ordinary one. The promotion of thin⁃thickness biodegradable films in cabbage planting in Guizhou not only can keep the yield of the cabbage, but also can improve ecological benefits and increase economic benefits. This helps to realize the scientific concept that clean waters and green mountains are invaluable assets.
Review
MA Fengan, ZHAO Guanghui, TIAN Cheng, JIA Yuzhe, LIU Tao
Abstract (
105 )
PDF (1232 KB)(
100
)
HTML (
1 )
This paper analyzed the common defects and their causes in the continuous⁃fiber⁃reinforced ⁃polymer⁃matrix composites and reviewed the latest research progress in the non⁃destructive testing methods of defects and their effect on the mechanical properties of the composites. In the aspect of defect detection, improving detection accuracy, accelerating detection data processing, and developing detection technology for special defects are the hotspots of the current research. The effect of macroscopic defects on the mechanical properties of the composites was qualitatively and quantitatively analyzed. The influencing factors mainly included the in⁃plane size, buried depth and shape of delamination defects, porosity, distribution concentration and shape of pore defects, and the direction, convexity and wrinkle angle of wrinkle defects. This paper provides a basis for the design and reliability evaluation of fiber⁃reinforced⁃polymer⁃matrix composites.
WANG Shilin, ZHU Jiawei, ZHANG Peng, WEI Xingyue, YANG Huaguang, ZENG Xiankui, YANG Weimin, JIAN Ranran
Abstract (
107 )
PDF (1102 KB)(
115
)
HTML (
3 )
As a mainstream technology for 3D printing, fused deposition modeling (FDM) has been received a wide application range. However, the insufficient strength of printing parts and slow molding speed are still the bottleneck for its development. Therefore, the researchers at home and in foreign countries have conducted in⁃depth research on this issue. This article explored various ways to improve printing strength from the perspectives of optimizing printing parameters and improving interlayer bonding, material modification, and process innovation. Meanwhile, the paper also analyzed the key factors that affect the molding efficiency of FDM from the two aspects of improving the printing method and optimizing the printing equipment and proposed the corresponding improvement methods. Finally, the comprehensive applications for improving printing strength and printing rate through artificial intelligence from the perspectives of printing path optimization and quality inspection were summarized.
WANG Yaomin, TIAN Huafeng, OUYANG Yuge, CAO Weiwei
Abstract (
90 )
PDF (3207 KB)(
164
)
HTML (
2 )
Polyvinyl alcohol (PVA) has great potential in the field of supramolecular material research. This paper introduced various supramolecular materials with different properties prepared using PVA through reversible covalent bonds and reversible non covalent bonds in recent years. The molecular design, synthesis methods, and potential mechanisms involved were discussed and analyzed. Finally, the problems in the research field of PVA⁃based supramolecular materials were summarized and analyzed, and the relevant suggestions and prospects were proposed.
WANG Bo, ZHANG Qian, GAO Yan, WU Longkun, LEI Ying, LIU Nianjie
Abstract (
93 )
PDF (1722 KB)(
120
)
HTML (
2 )
At present, there are two main ways to modify epoxy resin from silicone, including physical blending and chemical copolymerization. Chemical copolymerization modification has been widely used and studied because of its excellent high⁃temperature and corrosion resistances. This paper introduced the new development process of silicone chemical copolymerization⁃modified epoxy resin and briefly described its reaction mechanism. The research progress in different modification methods was analyzed, and the applications for electronic and electrical packaging materials, adhesives, coatings and other fields were briefly described. Finally, the current problems in the silicone⁃modified epoxy resin were proposed, and its future development direction was prospected.
GUO Sanci, WANG Lei, YUAN Hongyue, YANG Yidan, LIU Xianhu, PAN Yamin
Abstract (
120 )
PDF (3718 KB)(
151
)
HTML (
3 )
With the intensification of global warming and the frequent occurrence of extremely high temperature weather, there is an increasingly urgent demand for the cooling of human body, buildings, equipment, etc. However, traditional cooling methods such as air conditioning systems consume a large amount of energy, leading to a significant increase in greenhouse gas emissions and seriously hindering the achievement of the goals for "Carbon peaking and carbon neutrality". The radiative cooling technology based on structural and material design provides a zero⁃energy consumption and eco⁃friendly cooling strategy for sustainable carbon neutrality through the selective and precise regulation of sunlight and mid⁃infrared spectrum. This article reviewed the research status and progress in the radiative cooling materials used in different fields and discussed their application prospects from different perspectives.