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《Advanced Powder Technology》2023,34(1):103838
Manganese sulfide (MnS) with high specific capacitance and low-cost merits, has been investigated as a potential electroactive material for supercapacitor. However, in practical application, MnS has been suffering from some disadvantageous issues such as insufficient electrical conductivity, serious particle agglomeration as well as huge volume change during continuous charges and discharges, which resulted in a limited specific capacitance, shortened working life and inferior rate performance. Engineering electrode materials with controlled nanostructure and composition is pivotal to improve electrichemical performance of supercapacitors. This paper introduces a facile in situ sulfuration method to fabricate MnS/NSC composite with Mn-hexamethylene tetramine coordination framework as precursor. The results indicated that MnS nanoparticles were highly dispersed and incorporated into nitrogen, sulfur-doped carbon microsheets in MnS/NSC composite. Carbon matrix effectively dispersed and confined the MnS nanoparticles, thus inhibiting aggregation, relieving volume change and retaining structural integrity. Moreover, the 2D conductive carbon matrix reduced the diffusion distance for ions and ensured fast electron delivery. As a result, MnS/NSC electrode delivered a tremendously boosted electrochemical performance for supercapacitor. A large capacitance value about 1881.8F/g was achieved at 1A/g. Even cycling for 3000 loops at 40 A/g, MnS/NSC electrode retained a large capacitance of 404.3F/g. Furthermore, an asymmetric capacitor based on assembly of MnS/NSC composite cathode and activated carbon anode was fabricated. As tested under a current density of 0.1 A/g, it delivered a capacitance of ~ 110.1F/g and achieved an energy density of 12.4 Wh kg?1 along with a power density of 3.03 kW kg?1. These results demonstrate the potential utilization of MnS/NSC composite as electrodes for energy conversion and storage devices and open up a route for material design for future energy storage devices. 相似文献
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The behavior of natural rubber–epoxidized natural rubber–silica composites based on wet masterbatch technique 下载免费PDF全文
Yueqiong Wang Lusheng Liao Jieping Zhong Dongning He Kui Xu Changjin Yang Yongyue Luo Zheng Peng 《应用聚合物科学杂志》2016,133(26)
Natural rubber–epoxidized natural rubber–silica composites were prepared by the wet masterbatch technique and the traditional dry mixing method. Performances of the composites based on different preparation methods were investigated with a moving die rheometer, an electronic universal testing machine, a dynamic mechanical analyzer, a nuclear magnetic resonance crosslink density analyzer, a rubber processing analyzer (RPA), a scanning electron microscope (SEM), and a transmission electron microscope (TEM). The RPA, SEM, and TEM analyses indicated that silica has better dispersion, lower filler–filler interaction, and better filler–rubber interaction in compounds based on the wet masterbatch technique, leading to improvements in mechanical strength and the dynamic mechanical and compression properties of the composites. It also indicates that composites prepared by the wet masterbatch technique have shorter scorch time, faster curing velocity, and higher crosslink density. The composites prepared by the wet materbatch technique also have lower rolling resistance, which is an important property for their use as a green material for the tire industry. © 2016 Wiley Periodicals, Inc. J. Appl. Polym. Sci. 2016 , 133, 43571. 相似文献
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The toughening of polyamide 6 (PA 6) with β-nucleated thermoplastic vulcanizates (TPVs) based on polypropylene (PP)/ethylene–propylene–diene rubber grafted with maleic anhydride (EPDM-g-MAH) blends was studied. A series of TPVs without and with different dosage of β-nucleating agent (β-NA) were prepared and used to toughen PA 6 at the same proportion. Differential scanning calorimetry (DSC) and wide-angle X-ray diffraction (WAXD) measurements showed that β crystals of PP were effectively induced in the TPVs. The PA 6 blends toughened with β-nucleated TPVs (β-TPVs) exhibit significantly enhanced toughness, balanced mechanical properties and thermal properties compared with PA 6 toughened by TPV without β-NA or only by EPDM-g-MAH. Phase morphologies of the blends characterized by scanning electron microscopy (SEM) showed that better interfacial adhesion caused by the migration of β-NA from PP to PA 6/PP interface and PP/EPDM-g-MAH interface gives rise to more uniform dispersion and smaller size of the dispersed phase; moreover, the core–shell structure comprised of rubber particles enveloped by PP on the surface, brings about easier and stronger interference of the stress field of EPDM phase. 相似文献
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In this study, the effect of different levels and loadings of modified nanoclay (NC), nanoclay 1 CEC, 2 CEC and 4 CEC, cation exchange capacity on mechanical properties and adhesion strength of maleic anhydride grafted ethylene-propylene-diene terpolymer (EPDM-g-MAH)/nylon 66 systems were investigated. Fourier transform infrared (FTIR) data confirmed the reaction mechanism between maleic anhydride in the polymer backbone and the organomodifier of the nanoclay. Dynamic mechanical analysis (DMA) results showed that on increasing the levels of nanoclay modification, the storage modulus (Eʹ) increased as well as the glass transition temperature (Tg) was slightly shifted to lower temperature and the height of the damping property (tan δ) peaks decreased. The results revealed that the use of the three levels of modified clay with EPDM-g-MAH had significant effects on the tensile strength and elongation at break, especially at 5 parts per hundred rubber by weight (phr) filler content. Whereas in the case of lower nanoclay filler contents (i.e. 1 and 3 phr) the results clarified that they had little effect on tensile and elongation at break values. Pull-out adhesion tests showed that the adhesion force of NC 2 CEC nanocomposite was approximately twice that of the virgin polymer while the nanocomposite NC 4 CEC showed inferior adhesion values, especially at 5 phr filler content. Scanning electron microscopy (SEM) clarified that good wettability of elastomer took place, especially in case of NC 2 CEC which in turn led to an enhancement of the adhesion force between the elastomer and the nylon 66 cord. 相似文献
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Ding Hongda Luo Zirong Kong Na Li Zhifeng Zhao Pengfei Zhang Jizhen Tao Jinlong 《Journal of Materials Science: Materials in Electronics》2022,33(19):15563-15573
Journal of Materials Science: Materials in Electronics - Sensors, as one of the crucial components of wearable electronics, have attracted much attention due to their extensive application in... 相似文献
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Jing Chen Jieping Zhong Sidong Li Bingbing Wang Rongkan Pan Lijun Gao 《Polymer Engineering and Science》2018,58(7):1043-1052
Siliceous earth (SE), which has a special morphology and structure, was selected as filler of natural rubber (NR) and mechanical properties of compounds were analyzed. Two processes were employed to prepare SE/NR compounds described as mechanical mixing method and latex method, respectively. Cure characteristics, mechanical properties of the vulcanizates prepared from the masterbatches were compared with those prepared by mechanical mixing method. X‐ray diffraction results of NR/SE vulcanizations indicated that mechanical mixing above the latex process facilitated the intercalation of NR into the galleries of SE. The results of mechanical properties show that SE has good reinforcing properties on NR both by latex or mechanical mixing process. By comparison, H samples show slightly higher crosslink density, tensile strength, 300% modulus, and lower elongation at break than M sample in same loading. But in the aspect of dynamic properties there exist obviously difference between latex and mechanical mixing process. Rubber processing analyzer (RPA) results showed that uncured M samples showed obviously higher storage modulus than that of H samples. The heat build‐up of M30 is much lower than that of H30. These behaviors indicated better dynamitic properties when the masterbatches prepared by the predispersing method was utilized. POLYM. ENG. SCI., 58:1043–1052, 2018. © 2017 Society of Plastics Engineers 相似文献
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Nattapon Uthaipan Methakarn Jarnthong Zheng Peng Banja Junhasavasdikul Charoen Nakason Anoma Thitithammawong 《Journal of Polymer Research》2017,24(8):118
The isothermal and non-isothermal crystallizations of PP in neat form and in the TPVs EPDM/PP and EOC/PP were investigated using differential scanning calorimetry (DSC). The crystallization of PP was systematically studied by fitting mathematical models, and was later confirmed by X-ray diffraction (XRD) and by scanning electron microscopy (SEM). The experiments revealed that crosslinked elastomer particles first accelerated the primary nucleation of the PP matrix, acting effectively as a nucleating agent that reduces the induction time while increasing the nucleation efficiency. In the secondary nucleation regime (growth of spherulites), the crosslinked elastomer particles enhanced crystal growth rate, reducing the nucleation energy contribution from PP chain folding. Moreover, the crosslinked elastomer particles increased the final thickness of PP lamellae from that of neat PP, and this was corroborated by the XRD results. On comparing the two types of elastomer, it was found that the EOC particles were more effective in heterogeneous cell nucleation than the EPDM particles. The morphological study by SEM revealed completely altered PP spherulite size and shape, as well as their altered distribution, affected by heterogeneous nucleation effects of the crosslinked elastomer particles. 相似文献