THE CHEMISTRY OF ETHYLENE OXIDE: III. REACTION OF ETHYLENE OXIDE IN AMINE SOLUTION

1951 ◽  
Vol 29 (7) ◽  
pp. 585-596 ◽  
Author(s):  
A. M. Eastham ◽  
B. deB. Darwent
Keyword(s):  
Ethylene Oxide ◽  
Chemical Nature ◽  
Low Dielectric Constant ◽  
Specific Rate ◽  
Low Dielectric ◽  
Wide Range ◽  
Specific Rate Constant ◽  
Solutions Of Electrolytes ◽  
Strong Acids ◽  
Basic Strength

A kinetic study has been made of the reaction of ethylene oxide in pyridine solution in the presence of strong acids. The rate has been found to be dependent upon the concentration of acid and of oxide over a wide range of concentrations at 25°C. The specific rate constant, however, varies markedly with the nature of the acid anion and appears to decrease with increasing basic strength of the anion. The absence of large salt effects seems to indicate that the anion effect is of a physical rather than chemical nature and the results are therefore tentatively attributed to the nature of solutions of electrolytes in solvents of low dielectric constant.

Dielectric Properties Of Low Dielectric Constant Polymeric Materials

1995 ◽  
Vol 381 ◽  
Author(s):  
Flora S. Ip ◽  
Chiu Ting
Keyword(s):  
Dielectric Constant ◽  
Dielectric Properties ◽  
High Performance ◽  
Metal Layer ◽  
Polymeric Materials ◽  
Signal Propagation ◽  
Low Dielectric Constant ◽  
Low Dielectric ◽  
Wide Range ◽  
Metal Insulator Metal

AbstractMultilevel interconnects for high performance ULSI need low dielectric constant materials for inter-metal layer dielectric, or ILD, to reduce signal propagation delay, power consumption and cross talk noises. We have studied the physical, dielectric and processing properties of a wide variety of promising low dielectric polymeric materials for ILD applications. This paper presents capacitance values measured over a wide range of temperature, and a summary of the measured dielectric properties. The anisotropy 1,2 of dielectric properties were determined experimentally, the vertical (out-of-plane) dielectric properties were determined by MIM (Metal-Insulator-Metal) measurements, and the horizontal (in-plane) dielectric properties were determined by intra-line measurements of sub-half micron serpentine and comb test structures.

Preparation and Properties of Polyisoimides as a Highly Dimensionally Stable Polyimide Precursor with Low Dielectric Constant

1997 ◽  
Vol 9 (3) ◽  
pp. 333-344 ◽  
Author(s):  
Hiroshi Seino ◽  
Osamu Haba ◽  
Amane Mochizuki ◽  
Masahiro Yoshioka ◽  
Mitsuru Ueda
Keyword(s):  
Dielectric Constant ◽  
Dielectric Constants ◽  
Isomerization Reaction ◽  
Low Dielectric Constant ◽  
Low Dielectric ◽  
Fluorinated Polyimides ◽  
Wide Range ◽  
Biphenyltetracarboxylic Dianhydride ◽  
Polyimide Precursor ◽  
Dipolar Aprotic Solvents

Fluorinated polyimides (PIs) with low dielectric constant and high dimensional stability have been developed using polyisoimides (PIIs) as a polyimide precursor. The PIIs were prepared by the ring-opening polyaddition of the dianhydrides pyromellitic dianhydride, biphenyltetracarboxylic dianhydride and 4, 4′-hexafluoropropylidenedi(phthalic anhydride) with the diamines 2, 2′-dimethylbenzidine and 2, 2′-bis(trifluoromethyl)benzidine, followed by treatment with trifluoroacetic anhydride/triethylamine or dicyclohexylcarbodiimide in N;N-dimethylacetamide. The PIIs were soluble in a wide range of solvents including dipolar aprotic solvents, cyclohexanone and tetrahydrofuran at room temperature, and easy to convert to corresponding PIs by high thermal treatment. The resulting PIs showed low dielectric constants of less than 3 at 1 MHz as well as low CTEs. Furthermore, during the isomerization reaction, migration of copper in the PI film was hardly observed.

scholarly journals SOLVENT EFFECT ON IODIDE EXCHANGE

1951 ◽  
Vol 29 (9) ◽  
pp. 790-803 ◽  
Author(s):  
R. D. Heyding ◽  
C. A. Winkler
Keyword(s):  
Dielectric Constant ◽  
Dissociation Constants ◽  
Hydrogen Iodide ◽  
Low Dielectric Constant ◽  
Specific Rate ◽  
Iodide Ions ◽  
Low Dielectric ◽  
The Individual ◽  
High Dielectric ◽  
Triple Ion

The exchange of iodine between hydrogen iodide and n-butyl iodide has been studied in several organic solvents. In solvents of high dielectric constant (methanol, ethanol, n-butanol), exchange occurred by reaction of iodide ions with butyl iodide. In solvents of low dielectric constant (n-hexanol, n-dodecanol, acetic acid), it appeared that exchange also occurred between butyl iodide and the associated IHI− triple ion. Orders of magnitude of the individual specific rate constants have been calculated, using approximate values for the dissociation constants of hydrogen iodide. The rate constant – dielectric constant relation developed by Laidler and Eyring for ion – neutral molecule reactions appears to hold for exchange in homologous solvents, but does not seem to represent the effect of nonhomologous solvents. This discrepancy and the small differences observed in activation energies for the various exchanges may be due to solvation effects.

Sign in / Sign up

Export Citation Format

Share Document