Suppression of elevated temperature space charge accumulation in polypropylene/elastomer blends by deep traps induced by surface-modified ZnO nanoparticles

2017 ◽  
Vol 153 ◽  
pp. 103-110 ◽  
Author(s):  
Bin Dang ◽  
Qi Li ◽  
Yao Zhou ◽  
Jun Hu ◽  
Jinliang He
2016 ◽  
Vol 14 (3) ◽  
pp. 785-794 ◽  
Author(s):  
Nurun Nahar Rabin ◽  
Jannatul Morshed ◽  
Hashi Akhter ◽  
Md. Saidul Islam ◽  
Md. Asjad Hossain ◽  
...  

Abstract Surface modification of Zinc oxide nanoparticles (ZnO) with γ-aminopropyltriethoxy silane (APTES) was investigated. Successful surface modification of the nanoparticles was confirmed experimentally by X-ray Photoelectron Spectroscopy (XPS) and Fourier transform infrared spectroscopy (FT-IR). The effect of the surface modifier concentration on the grafting density and surface area was studied by CHN elemental analysis and Brunauer–Emmett–Teller (BET) analysis. The photocatalytic activity and UV shielding ability of the surface-modified particles prepared in water-ethanol solvent in the presence of the surface modifiers were compared to those of non-modified particles. As a case study, It was observed by methylene blue (MB) dye degradation experiment that the photocatalytic activity in the presence of modified nanoparticles was lower than that observed with non-modified ZnO nanoparticles. Dispersion stability tests visually showed that APTES grafted nanoparticles had acquired better stability than non-modified ZnO nanoparticles in aqueous solution.


RSC Advances ◽  
2016 ◽  
Vol 6 (54) ◽  
pp. 48720-48727 ◽  
Author(s):  
Yao Zhou ◽  
Jun Hu ◽  
Bin Dang ◽  
Jinliang He

Introduction of surface modified nano-TiO2 increases shallow traps and enhances charge carrier mobility so as to suppress space charge accumulation.


2017 ◽  
Vol 416 ◽  
pp. 628-638 ◽  
Author(s):  
Mohsen Hajibeygi ◽  
Meisam Shabanian ◽  
Mehrdad Omidi-Ghallemohamadi ◽  
Hossein Ali Khonakdar

Materials ◽  
2020 ◽  
Vol 13 (6) ◽  
pp. 1333
Author(s):  
Xiangjin Guo ◽  
Zhaoliang Xing ◽  
Shiyi Zhao ◽  
Yingchao Cui ◽  
Guochang Li ◽  
...  

This paper describes the effects of α-Al2O3 nanosheets on the direct current voltage breakdown strength and space charge accumulation in crosslinked polyethylene/α-Al2O3 nanocomposites. The α-Al2O3 nanosheets with a uniform size and high aspect ratio were synthesized, surface-modified, and characterized. The α-Al2O3 nanosheets were uniformly distributed into a crosslinked polyethylene matrix by mechanical blending and hot-press crosslinking. Direct current breakdown testing, electrical conductivity tests, and measurements of space charge indicated that the addition of α-Al2O3 nanosheets introduced a large number of deep traps, blocked the charge injection, and decreased the charge carrier mobility, thereby significantly reducing the conductivity (from 3.25 × 10−13 S/m to 1.04 × 10−13 S/m), improving the direct current breakdown strength (from 220 to 320 kV/mm) and suppressing the space charge accumulation in the crosslinked polyethylene matrix. Besides, the results of direct current breakdown testing and electrical conductivity tests also showed that the surface modification of α-Al2O3 nanosheets effectively improved the direct current breakdown strength and reduced the conductivity of crosslinked polyethylene/α-Al2O3 nanocomposites.


2012 ◽  
Vol 562-564 ◽  
pp. 250-254 ◽  
Author(s):  
Lei Zhang ◽  
Hong Liang Ge ◽  
Min Zhong

ZnO nanorods and nanoparticles were successfully modified by NDZ-311w titanate coupling agent. The result of lipophilic degree showed that both ZnO nanocrystals with different morphologies were well lipophilic. Although both values of lipophilic degree firstly became larger and then smaller with the increase of modifier dosage, the different maximal lipophilic degree of ZnO nanorods and nanoparticles could be 68.8% and 77.9%, respectively. By comparing the two curves of lipophilic degree of surface modified ZnO nanocrystals with different morphologies, it could be demonstrated that the optimal dosage of NDZ-311w titanate coupling agent is inversely proportional to the grain size. TEM and XRD results showed that the grain size of ZnO nanoparticles were much smaller than that of ZnO nanorods, which can be the evidence for the equation. Otherwise, the surface modified ZnO nanoparticles displayed better dispersion than unmodified ones.


Materials ◽  
2019 ◽  
Vol 12 (21) ◽  
pp. 3540 ◽  
Author(s):  
Peng Qiu ◽  
Jun-Qi Chen ◽  
Wei-Feng Sun ◽  
Hong Zhao

To achieve high direct current (DC) dielectric performance of crosslinked polyethylene (XLPE) applied for insulated cable, the auxiliary crosslinking agent of trimethylolpropane trimethacrylate (TMPTMA) is employed in photon-initiated crosslinking process to the present polar-molecular group which will introduce deep traps for charge carriers. The space-charge accumulation and electrical conductance of XLPE are observably suppressed due to the deep traps deriving from the TMPTMA crosslinkers that are chemically connecting (grafted onto) polyethylene molecules. Thermally stimulated depolarization current tests and first-principles calculations consistently demonstrate a trapping mechanism of impeding charge injection and carrier transport in XLPE with TMPTMA crosslinkers. The characteristic cyclic anhydrides with coupled carbonyl groups are used as auxiliary crosslinkers to promote crosslinking efficiency and provide polar groups to polyethylene molecules which can be effectively fulfilled in industrial cable production. The results of infrared spectroscopy show that the auxiliary crosslinkers have been successfully grated to polyethylene molecules through the UV-initiation process. The space-charge characteristics achieve a significant improvement consistent with the theoretical estimation that deeper electronic traps can be introduced by auxiliary crosslinker and will consequently suppress space-charge accumulation through a trapping mechanism. Meanwhile, the conductivity of XLPE observably increases after using TMPTMA auxiliary crosslinkers at various temperatures of cable operation. The first-principles calculations also demonstrate that substantial electronic bound states have been introduced at the band edge of polyethylene molecules crosslinked by TMPTMA, leading to reduction in electrical conductivity. On the advantage of ameliorating DC dielectric performance by way of UV-initiated crosslinking process, the present research suggests a substantial strategy in XLPE cable industrial productions.


Sign in / Sign up

Export Citation Format

Share Document