Solvent Diffusion in Selected Polyimide Films

1989 ◽  
Vol 167 ◽  
Author(s):  
W. P. Pawlowski ◽  
M. I. Jacobson ◽  
M. E. Teixeira ◽  
K. G. Sakorafos

AbstractThe absorption of several solvents including methylene chloride (MC), methyl chloroform (MCF), gamma-butyrolactone (BLO), dibromomethane (DBRO), 1,2-dichloroethane (DCE), and 1,2-dichloropropane (DCP) in Kapton H*, Upilex S**, and Upilex R** polyimide film was measured gravimetrically. A significant difference in the rate and amount of absorption of these chemicals by the various films was observed. Complimentary Rutherford Backscattering Spectrometry (RBS) measurements provided additional information regarding the amount of solvent absorbed and mode of transport.

1983 ◽  
Vol 27 ◽  
Author(s):  
L. Salamanca-Riba ◽  
B.S. Elman ◽  
M.S. Dresselhaus ◽  
T. Venkatesan

ABSTRACTRutherford backscattering spectrometry (RBS) is used to characterize the stoichiometry of graphite intercalation compounds (GIC). Specific application is made to several stages of different donor and acceptor compounds and to commensurate and incommensurate intercalants. A deviation from the theoretical stoichiometry is measured for most of the compounds using this non-destructive method. Within experimental error, the RBS results agree with those obtained from analysis of the (00ℓ) x-ray diffractograms and weight uptake measurements on the same samples.


2019 ◽  
Vol 37 (2) ◽  
pp. 020601 ◽  
Author(s):  
Grazia Laricchiuta ◽  
Wilfried Vandervorst ◽  
Ian Vickridge ◽  
Matej Mayer ◽  
Johan Meersschaut

1990 ◽  
Vol 23 (15) ◽  
pp. 3675-3682 ◽  
Author(s):  
Michael A. Masse ◽  
Russell J. Composto ◽  
Richard A. L. Jones ◽  
Frank E. Karasz

1997 ◽  
Vol 504 ◽  
Author(s):  
S. C. Choi ◽  
K. H. Kim ◽  
H-J. Jung ◽  
C. N. Whang ◽  
S. K. Koha

ABSTRACTPolyimide films are modified by ion assisted reaction method using various ion beams in various gases environments. Amount of ion and blown gases rate were changed from 5 × 1014 to 1 × 1017 and from 0 to 8 sccm, respectively. Wetting angles between water and polyimide films modified by Ar+ ion without oxygen blowing decrease from 67° to 400° and surface free energies increase from 46 to 64 dyne/cm2. Wetting angle of polyimide films modified by Ar+ ion in an oxygen environment decreases to 12° and surface free energy increases to 72 dyne/cm2. The lowest wetting angle was obtained by oxygen ion irradiation in the oxygen gas environment and its value was 7°. In the case of polyimide film modified by Ar+ ions in an oxygen environment, the wetting angle increases up to 65° when it kept in air and that increases up to 46° when it kept in water after 5 day. In the case of polyimide film modified by O2+ ion in oxygen environment, however, the wetting angle of polyimide film dose not increase. X-ray photoelectron analysis shows that the chemical bonds between polyimide components are severed by ion irradiation and hydrophilic groups such as CO and C=O are formed by the reaction between newly formed radicals and blown oxygen. It was found that adhesion between Cu and polyimide modified by ion assisted reaction was improved. The main reason of the enhanced adhesion is due to the reaction between Cu and C-O or C=O groups formed by ion assisted reaction on the polyimide surface.


2022 ◽  
pp. 004051752110694
Author(s):  
Hao Yu ◽  
Christopher Hurren ◽  
Xin Liu ◽  
Stuart Gordon ◽  
Xungai Wang

Comfort is a key feature of any clothing that relates significantly to softness of the fiber, yarn and fabric from which is it constructed. A known softness assessment method for fibers is the resistance to compression test. This traditional test only provides a single force value for the resistance of a loose fiber sample using a fixed mass under compression. In this research, a modified resistance to compression test was introduced to show the effects of repeated compression, providing more information about the softness and resilience of selected fibers. Three different natural fiber types, including wool, cotton and alpaca were compared using this new approach. The results showed compression profiles were quite different for different fiber types as well as for the same fibers with different diameters. While the diameters of the wool and alpaca samples were similar (18.5 μm), the modified resistance to compression values were significantly higher for wool (with a peak value at 9.5 kPa compared to 2.1 kPa for alpaca). Cotton was different from wool and alpaca but showed a similar modified resistance to compression value (10.4 kPa) to wool. During cycles of compression, modified resistance to compression peak values decreased slightly and then tended to be constant. Even though the structures of wool, cotton and alpaca were quite different, there was no significant difference in the magnitude of decline in modified resistance to compression peak values. This means that the modified resistance to compression test is able to provide additional information on the resilience characteristics of different natural fibers, and can reveal the resistance behavior of fiber samples during cyclic compression.


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