Concerning the correlation between dielectric breakdown field strength and lattice constant in alkali halides

1976 ◽  
Vol 11 (3) ◽  
pp. 576-577 ◽  
Author(s):  
P. R. Couchman ◽  
G. R. Proto ◽  
C. L. Reynolds
Materials ◽  
2021 ◽  
Vol 14 (7) ◽  
pp. 1596
Author(s):  
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.


1989 ◽  
Vol 167 ◽  
Author(s):  
S. Jeng ◽  
M. Xu ◽  
P. L. Liu ◽  
H. S. Kwok ◽  
C. J. Lee

AbstractPolyimides are finding increased use as dielectric materials in multi-level metallization technology, which is the key to high-density packaging applications for microelectronics.Newly developed photosensitive polyimidesiloxane (SIM2000XL-RTS) has been evaluated in terms of thermal stability, photosensitivity and lithography as well as dielectric breakdown properties. The sensitivity to N2 laser exposure has been measured under optimized process conditions. We also find that SIM2000XL-RTS can be processed up to 350°C without significant decomposition. Micron-scale contact images can be successfully patterned by both N2 laser and conventional UV lamp exposure. The dielectrical breakdown field strength of SIM2000XL-RTS is about 4 MV/cm by sandwich measurements.


2014 ◽  
Vol 975 ◽  
pp. 168-172
Author(s):  
Tiago Delbrücke ◽  
Igor Schmidt ◽  
Sergio Cava ◽  
Vânia Caldas Sousa

The addition of different dopants affects the densification and electrical properties of TiO2 based varistor ceramics. The nonlinear current (I) and voltage (V) characteristics of titanium dioxide are examined when doped with small quantities (0.5-2 at.%) of strontium oxide. This paper discusses the electrical properties of such an SrO doped TiO2 system, and demonstrates that some combinations produce electrical properties suitable for use as low voltage varistors. The high value of the nonlinear coefficient (α) (6.6), the breakdown field strength (Eb) (328 V/cm) and the leakage current (Ir) (0.22 mA/cm2) obtained in a system newly doped with SrO, are all adequate properties for application in low voltage varistors.


2020 ◽  
Vol 8 (38) ◽  
pp. 13405-13414
Author(s):  
Zhi-Gang Liu ◽  
Zhen-Hua Tang ◽  
Song-Cheng Hu ◽  
Di-Jie Yao ◽  
Fei Sun ◽  
...  

Doping decreased oxygen vacancies in ceramics, resulting in high breakdown field strength and excellent energy storage performances.


Sign in / Sign up

Export Citation Format

Share Document