Materials
·
2021
·Vol. 14
·期 7
·1596
·
IF 3.623
Peng Zhang,Yongqi Zhang,Xuan Wang,Jiaming Yang,Wenbin Han
Blending thermoplastic elastomers into polypropylene (PP) can make it have great potential for high-voltage direct current (HVDC) cable insulation by improving its toughness. However, when a large amount of thermoplastic elastomer is blended, the electrical strength of PP will be decreased consequently, which cannot meet the electrical requirements of HVDC cables. To solve this problem, in this paper, the inherent structure of thermoplastic elastomer SEBS was used to construct acetophenone structural units on its benzene ring through Friedel–Crafts acylation, making it a voltage stabilizer that can enhance the electrical strength of the polymer. The DC electrical insulation properties and mechanical properties of acetylated SEBS (Ac-SEBS)/PP were investigated in this paper. The results showed that by doping 30% Ac-SEBS into PP, the acetophenone structural unit on Ac-SEBS remarkably increased the DC breakdown field strength of SEBS/PP by absorbing high-energy electrons. When the degree of acetylation reached 4.6%, the DC breakdown field strength of Ac-SEBS/ PP increased by 22.4% and was a little higher than that of PP. Ac-SEBS, with high electron affinity, is also able to reduce carrier mobility through electron capture, resulting in lower conductivity currents in SEBS/PP and suppressing space charge accumulation to a certain extent, which enhances the insulation properties. Besides, the highly flexible Ac-SEBS can maintain the toughening effect of SEBS, resulting in a remarkable increase in the tensile strength and elongation at the break of PP. Therefore, Ac-SEBS/PP blends possess excellent insulation properties and mechanical properties simultaneously, which are promising as insulation materials for HVDC cables.Keywords:polypropylene;voltage stabilizer;HVDC cable;thermoplastic elastomer
研究领域:
材料科学
·
电气工程
✓ 已验证
产品关联
DOI
PubMed
高影响因子
ACS Applied Energy Materials
·
2023
·
IF 6.4
Penghao Song,Surong Zheng,Zaka Ullah,Zairui Yang,Penghao Zhu,Aihua He,Cunguo Wang,Qi Li
The shuttle effect of lithium polysulfides on a positive electrode and the uncontrollable growth of lithium dendrites on a negative electrode are the two fundamental crucial problems of lithium–sulfur batteries (LSBs). These problems have led to low actual specific capacity and poor rate performance of these batteries. In order to resolve these issues at both electrodes simultaneously, we used Fe and Co bimetallic atoms to dope the three-dimensional dodecahedron material ZIF-8, which is used as a monomer to construct a functional modified separator. Owing to the porous structure, high specific surface area, notable interfacial electron conductivity after carbonization, and the synergistic catalytic effect of Fe and Co bimetallic doping, the FeCoDA-CN@PP separator suppresses the shuttle effect of lithium polysulfides (LiPSs) on the positive electrode and ensures the higher ion/electron rapid diffusion and hence efficient lithium growth during the cycling on the negative electrode. The demonstrated LSBs with the FeCoDA-CN@PP separator deliver a specific discharge capacity of 1404 mAh g–1 at 0.1C. After 500 provided cycles at a rate of 1C, it still offers a specific discharge capacity of 541 mAh g–1 and a stable Coulombic efficiency of >98% with a capacity decay rate of 0.08% per cycle. At a discharge rate of 1 mA cm–2, the symmetrical battery with the FeCoDA-CN@PP separator was still able to maintain a stable voltage distribution and an overpotential of 31 mV after 500 h. The outcomes pave an auspicious approach for the development of LSBs with long-cycle life and higher capacity, which may further promote the industrialization and commercialization of LSBs.
研究领域:
材料科学
·
电化学
·
能源存储与转换
✓ 已验证
产品关联
DOI
高影响因子
Materials Research Express
·
2019
·Vol. 6
·期 11
·115345
·
IF 1.449
Suwei Wang,Ping Xue,Mingyin Jia,Ke Chen
The foamed wood-polymer composites with polypropylene (PP) and polyolefin elastomer (POE) blends as matrix were prepared by a co-rotating twin-screw extruder and a single-screw extruder foaming system in this paper. To improve the dispersion uniformity of materials in the samples, a cavity transfer mixer was introduced to the single-screw extruder foaming system. Besides, the effects of both the nucleating agent and the coupling agent on the melt flowability, cell morphology and mechanical properties of the samples were investigated. The nanoparticles were also added to study the effect of nano-nucleating agent on the properties of the foamed samples. The experimental results show that the addition of talc and maleic anhydride grafted polypropylene (MAH-g-PP) resulted in the decrease of the melt flow rate and the increase of the Vicat softening temperature. But the addition of nanoparticles improved the melt flowability and reduced the softening temperature of the samples. Compared with talc, the addition of nanoparticles increased the impact strength of the samples by 6%. Moreover, the minimum cell size and the maximum cell density were obtained with the value of 62 μm and 2.8 × 104 cells cm−3, when the content of both talc and MAH-g-PP were 10 phr. Affected by the cell morphology, the maximum impact strength, tensile strength and flexural strength of the samples were also obtained with the value of 6.6 kJ m−2, 8.3 MPa and 22.6 MPa.
研究领域:
材料科学
·
高分子化学
✓ 已验证
产品关联
DOI
高影响因子
MATERIALS RESEARCH INNOVATIONS
·
2016
·
IF 0
Ling Liu,Xiuli Wang,Lisi Xie,Sile He
Shell cross-linked core–shell nanoparticles (SCCSN) with organic montmorillonite as the core and cross-linked polymethacrylate (PMMA) as the shell were prepared through seeded emulsion polymerisation. Scanning electron microscopy and transmission electron microscopy images of SCCSN show that each of the SCCSN is spherical with core–shell structure. The thermal properties and rheological behaviour of polypropylene (PP)/SCCSN composites with different proportions of SCCSN were systematically studied using a thermogravimetric analyser and an RT-2000 high-pressure capillary rheometer, respectively. The existence of SCCSN improves the thermal properties of PP, and the thermostability of the composite increases with increasing SCCSN content. The formed composite is a non-Newtonian pseudoplastic fluid with a similar processing behaviour to PP. The rheological parameters (e.g. shear stress, apparent viscosity and flow activation energy) of the composite decrease as SCCSN fills in. These data indicate that using SCCSN does not affect the processing fluidity of PP but improves its processability.
研究领域:
材料科学
·
热分析
·
高分子化学
✓ 已验证
产品关联
DOI
Nanomaterials
·
2021
·Vol. 11
·期 10
·2488
·
IF 5.076
Jian Gao,Ziming Li,Ziqi Deng,Meihua Liu,Wei Wei,Chunbai Zheng,Yifan Zhang,Shusen Chen,Pengyang Deng
Mercury is one of the most toxic heavy metals that can cause terrible disease for human beings. Among different absorption materials, MOF (metal–organic framework) materials show potential as very attractive materials for the rapid removal of mercury. However, the instability and difficulty for regeneration of MOF crystals limit their applications. Here, a continuous sulfur-modified MOF (UiO-66-NHC(S)NHMe) layer was synthesized in situ on polymeric membranes (PP non-woven fabrics) by post-synthetic modification and used for rapid mercury removal. The MOF-based membrane (US-N) showed high selectivity for mercury in different aqueous systems, which is better than sulfur-modified MOF powders. A thinner MOF layer on US-N showed a much better mercury ion removal performance. US-N with a 59.3 nm MOF layer could remove more than 85% of mercury in 20 min from an aqueous solution. In addition, the US-N can simply regenerate several times for mercury removal and maintain the initial performance (removal ratio > 98%), exhibiting excellent durability and stability. This work promotes the application of MOF materials in the rapid removal of hazardous heavy metal ions from practical environments.Keywords:metal–organic frameworks;membrane;mercury removal;rapid;regenerable
研究领域:
环境科学
·
材料科学
✓ 已验证
产品关联
DOI
PubMed
高影响因子
SEPARATION AND PURIFICATION TECHNOLOGY
·
2021
·
IF 7.312
Xiao-Han Pan,Ling-Xiao Fu,Huan Wang,Yi Xue,Jian-Hua Zu
A novel sulfydryl-functionalized adsorbent PP-g-GMA@MEA for recovery of Ag(I) was synthesized by γ-ray induced simultaneous grafting of glycidyl methacrylate (GMA) onto polypropylene (PP) non-woven fabric, followed by ring-opening processes with mercaptoethylamine (MEA). The obtained adsorbents before and after adsorption of Ag(I) were fully characterized by SEM, EDS, FT-IR spectra, XRD and XPS. Batch adsorption experiments were carried out to evaluate adsorption abilities of the adsorbents under high acidity. The adsorption kinetics of Ag(I) were well fitted with pseudo-second-order kinetics model. The maximum adsorption capacity calculated by the Langmuir isotherm model was 262.51 mg/g at 25 °C. EDS, XRD and XPS analyses confirmed the mechanism of adsorption under high acidity was chelating reaction between -SH and Ag(I) and ion exchange adsorption towards [Ag(NO 3 ) 2 ] −1 . Through competitive adsorption tests, the PP-g-GMA@MEA was found remarkably selective towards Ag(I) when it coexisted with Cu(II), Co(II), Ni(II) and Cr(III) in high acidity medium. Therefore, the developed PP-g-GMA@MEA composite would be a promising adsorbent for Ag(I) recovery from industrial effluents.
研究领域:
环境科学
·
材料科学
✓ 已验证
DOI
高影响因子
JOURNAL OF VINYL & ADDITIVE TECHNOLOGY
·
2021
·Vol. 28
·期 2
·405-417
·
IF 1.993
Zhiping Xu,Zhenhua An,Yan Ye,Rui Yang
Owing to the widespread use of polypropylene (PP) nanocomposites, their stability in the environment is becoming increasingly relevant. Accordingly, a systematic study of the relationship between the characteristics of inorganic nanofillers and the environmental aging behavior of PP is necessary to determine the service life of PP nanocomposites in outdoor environments. Therefore, in this study, we systematically investigated the effects of the chemical composition, particle size, crystalline form, and amount of inorganic filler (CaCO 3 , Al 2 O 3 , SiO 2 , and ZnO) on the outdoor aging behavior of PP. The results of outdoor aging experiments showed that the filler composition affects the aging behavior of PP. It was found that SiO 2 and ZnO nanoparticles accelerate and retard the outdoor aging of PP, respectively. In addition, PP composites containing inorganic fillers with relatively large particles or more stable crystalline forms exhibit relatively slow aging. In the case of the fillers other than ZnO nanoparticles, increasing the filler content accelerates the outdoor aging of PP. The evolution of cracks in the exposed surfaces of PP composites during outdoor aging was observed by scanning electron microscopy. The CO 2 generated by PP composites during in situ gaseous degradation product detection corresponds well with the results of the outdoor aging experiments. This study elucidates the effects of inorganic fillers on the outdoor aging behavior of PP.
研究领域:
材料科学
·
环境科学
✓ 已验证
DOI
高影响因子
POLYMER COMPOSITES
·
2025
·
IF 4.7
Jiawei Wei,Fang Wang,Ruru Liu,Xiangying Chen,Zhongjie Zhang
Based on the micro-structure of wollastonite (WS) and bamboo flour (BF), a series of PP/WS/BF ternary composite materials are prepared using blending, twin-screw melt extrusion, and injection molding processes. The experiment shows that the formulation and processing technology play a significant impact on the structure, thermal, and mechanical properties of the composites. BF has a significant impact on the nucleation and crystallization of PP, while WS has almost no effect on PP. BF improves tensile strength and enhances the strength of composites; WS improves the bending strength and flexural modulus and enhances the rigidity of composites. Taking the W-B-30-1:3 sample as an example, its tensile performance is the highest at 23.33 MPa, as well as bending strength and flexural modulus of 26.23 and 904.67 MPa, respectively. The combination of BF and WS leads to an increase in storage modulus, a decrease in loss modulus, a decrease in loss factor, an increase in glass transition temperature, and a decrease in bonding factor of ternary composite materials. This work can enrich the scope of PP composite materials, and the composite materials are expected to have potential applications in the fields of automotive interior parts with lightweight. Highlights Heterogeneous bonding among fillers enhances crystallization of composites. Wollastonite is more conducive to improving the thermal stability of composites. Adding fillers can more effectively enhance mechanical properties. The use of fillers increases interfacial compatibility and bonding performance.
研究领域:
材料科学
·
复合材料工程
✓ 已验证
产品关联
DOI
高影响因子
POLYMERS & POLYMER COMPOSITES
·
2017
·
IF 0.25
Jiuqiang Song,Yan Qin,Jia Chen,Siwen Qin
In this paper, a continuous glass fiber-reinforced polypropylene prepreg was prepared by fiber treatment with a silane coupling agent and MAH-g-PP resin. Continuous glass fiber-reinforced polypropylene sheets were made from prepreg and PP mats by hot-pressing; they displayed exceptional performance. This paper studies the effects of maleic anhydride grafting on the polypropylene crystallinity and MAH-g-PP content in the prepreg, and the mechanical properties of the composites. The results showed that modifying PP with maleic anhydride decreased the tacticity of the polypropylene molecular chain, which reduced the crystallinity and melting point. An excellent interface formed between the polypropylene and fiber after the glass fiber was treated with a silane coupling agent and MAH-g-PP resin. The mechanical properties of the polymer materials displayed more favorable properties as MAH-g-PP content increased; the ideal MAH-g-PP content was 50%.
✓ 已验证
DOI
高影响因子
JOURNAL OF ELASTOMERS AND PLASTICS
·
2021
·
IF 1.833
Mingchao Li,Yi Wang,Chunhui Shen,Shanjun Gao
Flame retardant thermoplastic elastomer (TPE) with excellent mechanical properties and thermal oxidative aging resistance was prepared by dynamic vulcanization technology with ethylene-octene copolymer (POE) and polypropylene (PP) as raw materials. The paper first discussed the effect of the amount of vulcanizing agent on the properties of PP/POE TPE. Based on the study of tensile strength, elongation at break, cross-section morphology, processability and aging properties of TPE, it was found that the TPE prepared with 0.6 phr of bis(1-(tert-butylperoxy)-1-methylethyl)-benzene (BIPB) and 40/60 of PP/POE had the best properties. Then silicone powder (GM) is added to the traditional low-halogen bromine-phosphorus flame retardant system for flame retardant modification. The results show that the addition of GM can effectively enhance the stability of the carbon layer, prevent the material from dripping during combustion, and increase the residual carbon content of TPE at 800°C. When 3 phr of GM is combined with a bromine-phosphorus system. The comprehensive performance is the best, the limiting oxygen index (LOI) of TPE increased to 29.8%, reaching the V-0 level. At the same time, the processing fluidity and aging resistance of TPE materials have also been improved.
研究领域:
材料科学
·
高分子化学
✓ 已验证
产品关联
DOI
高影响因子
Materials
·
2018
·Vol. 11
·期 9
·1536
·
IF 2.467
Junlong Yao,Li Hu,Min Zhou,Feng You,Xueliang Jiang,Lin Gao,Qing Wang,Zhengguang Sun,Jun Wang
Multifunctional polymer composites with both high dielectric constants and high thermal conductivity are urgently needed by high-temperature electronic devices and modern microelectromechanical systems. However, high heat-conduction capability or dielectric properties of polymer composites all depend on high-content loading of different functional thermal-conductive or high-dielectric ceramic fillers (every filler volume fraction ≥ 50%, i.e.,ffiller≥ 50%), and an overload of various fillers (fthermal-conductivefiller+fhigh-dielectricfiller> 50%) will decrease the processability and mechanical properties of the composite. Herein, series of alumina/barium titanate/polypropylene (Al2O3/BT/PP) composites with high dielectric- and high thermal-conductivity properties are prepared with no more than 50% volume fraction of total ceramic fillers loading, i.e.,ffillers≤ 50%. Results showed the thermal conductivity of the Al2O3/BT/PP composite is up to 0.90 W/m·K with only 10% thermal-conductive Al2O3filler, which is 4.5 times higher than the corresponding Al2O3/PP composites. Moreover, higher dielectric strength (Eb) is also found at the same loading, which is 1.6 times higher than PP, and the Al2O3/BT/PP composite also exhibited high dielectric constant (εr= 18 at 1000 Hz) and low dielectric loss (tan δ ≤ 0.030). These excellent performances originate from the synergistic mechanism between BaTiO3macroparticles and Al2O3nanoparticles.Keywords:thermal conductivity;dielectric properties;synergistic effect;polymer composites;ceramic
研究领域:
材料科学
·
电气工程
·
复合材料
✓ 已验证
产品关联
DOI
PubMed
高影响因子
POLYMER COMPOSITES
·
2017
·
IF 2.324
Juan Chen,Zhen Huang,Wenxiao Lv,CuiCui Wang
In this study, sisal fiber (SF) was treated with graphene oxide (GO) by means of physical absorption method. Maleic anhydride grafted polypropylene (MAPP) was used to modify PP matrix. The GO-SF/MAPP-PP composites with different fiber loading were fabricated by using extrusion compounding and injection molding techniques. Scanning electron microscopy (SEM) micrographs of the fracture surface demonstrated that the interface adhesion between SF and PP matrix was enhanced by the combination treatment of GO and MAPP. X-ray diffraction (XRD) results demonstrated that GO could play a role of β-nucleating agent for PP crystallization. The combination treatment of GO and MAPP also displayed an effective enhancement on mechanical properties, melting temperature and water resistance of the GO-SF/MAPP-PP composite, which is an useful method to fabricate high performance natural fiber reinforced bio-composites. POLYM. COMPOS., 39:E113–E121, 2018. © 2017 Society of Plastics Engineers
研究领域:
材料科学
·
复合材料
✓ 已验证
产品关联
DOI
高影响因子
危险品化学品经营许可证（带存储）