Low Dielectric Constants of Soluble Polyimides Based on Adamantane

1997 ◽  
Vol 30 (16) ◽  
pp. 4646-4651 ◽  
Author(s):  
Yaw-Terng Chern ◽  
Hann-Chyan Shiue
Keyword(s):  
Dielectric Constants ◽  
Low Dielectric

ChemInform Abstract: Sol-Gel-Derived Mesoporous Silica Films with Low Dielectric Constants.

ChemInform ◽  
2001 ◽  
Vol 32 (10) ◽  
pp. no-no
Author(s):  
Seana Seraji ◽  
Yun Wu ◽  
Michael Forbess ◽  
Steven J. Limmer ◽  
Tammy Chou ◽  
...  
Keyword(s):  
Mesoporous Silica ◽  
Sol Gel ◽  
Dielectric Constants ◽  
Silica Films ◽  
Low Dielectric

Fabrication of low dielectric constant polyimide/TiO2 nanofibers with enhanced UV-light shielding properties

2018 ◽  
Vol 31 (8) ◽  
pp. 986-995
Author(s):  
Lei Wang ◽  
Guifen Gong ◽  
Junyao Shen ◽  
Jinsong Leng
Keyword(s):  
Dielectric Constant ◽  
Light Absorption ◽  
Composite Nanofibers ◽  
Uv Light ◽  
Dielectric Constants ◽  
Low Dielectric Constant ◽  
Number Density ◽  
Tio2 Nanofibers ◽  
Low Dielectric ◽  
Mechanical Tensile

Polyimide (PI)/titanium dioxide (TiO2) composite nanofibers (NFs) with average diameters of 200–250 nm were synthesized via electrospinning. The total number density of dipoles decreased significantly, owing to the porous structures and compact interface between TiO2 NPs and PI matrix. All PI/TiO2 NFs maintain low dielectric constants and losses. For example, the dielectric constants of PI/TiO2-6% NFs are all lower than 2.6, being exposed to temperatures from 25°C to 200°C. Meantime, the dielectric losses of PI/TiO2-6% NFs are below 0.005. For ultraviolet (UV)-light shielding performance, the PI/TiO2 NFs exhibited good UV-light shielding and corresponding anti-photoaging properties. The reason can be ascribed from high UV-light absorption and scattering ability in the TiO2 NPs. The best UV-light absorption (average: 3.71) and corresponding absorption decay (15.13%) were achieved for optimized PI/TiO2-6% NFs. Other fundamental characteristics, such as the thermal stability, mechanical tensile property, and hydrophobicity, were also investigated. Such low dielectric constant PI/TiO2 composite NFs can be alternatively chosen under a longtime UV-light exposing condition.

A facile method for the preparation of aliphatic main-chain benzoxazine copolymers with high-frequency low dielectric constants

2018 ◽  
Vol 9 (21) ◽  
pp. 2913-2925 ◽  
Author(s):  
Ming Zeng ◽  
Jiangbing Chen ◽  
Qingyu Xu ◽  
Yiwan Huang ◽  
Zijian Feng ◽  
...  
Keyword(s):  
Dielectric Properties ◽  
High Frequency ◽  
Main Chain ◽  
Polymerization Kinetics ◽  
Dielectric Constants ◽  
Low Dielectric

The effects of the reaction solvent on the preparation, polymerization kinetics, and high-frequency dielectric properties of aliphatic main-chain benzoxazine copolymers were investigated.

Poly(aryl ether ketone/sulfone)s containing ortho-methyl and pendant trifluoromethyl-substituted phenyl groups: Synthesis and properties

2012 ◽  
Vol 24 (8) ◽  
pp. 692-701 ◽  
Author(s):  
Chengyuan Shang ◽  
Xiaojuan Zhao ◽  
Junwei Li ◽  
Jingang Liu ◽  
Wei Huang
Keyword(s):  
Dielectric Constants ◽  
Polymer Chains ◽  
Light Transmittance ◽  
Cutoff Wavelength ◽  
Aryl Ether ◽  
Good Thermal Stability ◽  
Low Dielectric ◽  
Aryl Ether Ketone ◽  
Ether Ketone ◽  
Good Transparency

Two novel bisphenols, 1,1-bis(4′-hydroxy-3′,5′-dimethylphenyl)-1-(3′′-trifluoromethylphenyl)-2,2,2-trifluoroethane (4M6FDO) and 1,1-bis(4′-hydroxy-3′,5′-dimethylphenyl)-1-[3′′,5′′-bis(trifluoromethyl)phenyl]-2,2,2-trifluoroethane (4M9FDO), with methyl groups ortho-substituted to the phenol groups, bulky trifluoromethyl-substituted phenyl groups and trifluoromethyl groups in the structure, were synthesized and characterized. The bisphenols were polymerized with 4,4′-difluorobenzophenone and bis(4-fluorophenyl) sulfone, respectively, via a aromatic nucleophilic substitution polycondensation to afford four poly(aryl ether ketone/sulfone)s (PAEKs/PAESs) with the inherent viscosities of 0.32–0.52 dL g−1. The ortho-methyl and pendant trifluoromethyl-substituted phenyl groups endow the polymers with good solubility, the rigidity of the polymer chains increase the glass transition ( Tg) of the polymers to 197–235 °C. Flexible and tough films cast from N,N-dimethylacetamide showed good thermal stability, low dielectric constants of 2.67–2.73 and low water uptakes of 0.21–0.40%. Moreover, the polymers showed good transparency with light transmittance at 450 nm as high as 96% and cutoff wavelength as low as 285 nm. The PAEKs also exhibited low light-absorption at the optocommunication wavelengths of 1310 and 1550 nm.

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