Spontaneous Molecular Orientation of Polyimides Induced by Thermal Imidization. 2. In-Plane Orientation

1996 ◽  
Vol 29 (24) ◽  
pp. 7897-7909 ◽  
Author(s):  
Masatoshi Hasegawa ◽  
Takafumi Matano ◽  
Yoichi Shindo ◽  
Tokuko Sugimura
Keyword(s):  
Molecular Orientation ◽  
Plane Orientation ◽  
Thermal Imidization

Spontaneous molecular orientation of polyimides induced by thermal imidization (4): Casting- and melt-induced in-plane orientation

2010 ◽  
Vol 46 (1) ◽  
pp. 69-80 ◽  
Author(s):  
Junichi Ishii ◽  
Naoko Shimizu ◽  
Nobuaki Ishihara ◽  
Yasutaka Ikeda ◽  
Nobuyuki Sensui ◽  
...  
Keyword(s):  
Molecular Orientation ◽  
Plane Orientation ◽  
Thermal Imidization

scholarly journals In-plane orientation of polyimide chains induced by thermal imidization.

1994 ◽  
Vol 7 (2) ◽  
pp. 275-280 ◽  
Author(s):  
MASATOSHI HASEGAWA ◽  
TAKAFUMI MATANO ◽  
YOICHI SHINDO ◽  
TOKUKO SUGIMURA
Keyword(s):  
Plane Orientation ◽  
Thermal Imidization

Spontaneous molecular orientation of polyimides induced by thermal imidization (6). Mechanism of negative in-plane CTE generation in non-stretched polyimide films

2010 ◽  
Vol 46 (4) ◽  
pp. 681-693 ◽  
Author(s):  
Junichi Ishii ◽  
Aya Takata ◽  
Yoko Oami ◽  
Rikio Yokota ◽  
Leonid Vladimirov ◽  
...  
Keyword(s):  
Molecular Orientation ◽  
Polyimide Films ◽  
Thermal Imidization

Internal Stress Development In Spin Coated Polyimide Films

1991 ◽  
Vol 227 ◽  
Author(s):  
Michael T. Pottiger ◽  
John Coburn
Keyword(s):  
Internal Stress ◽  
Molecular Orientation ◽  
Coefficient Of Thermal Expansion ◽  
Internal Stresses ◽  
Processing Conditions ◽  
Heating Rates ◽  
Polyimide Films ◽  
Plane Orientation ◽  
Relaxation Effects ◽  
Cte Mismatch

ABSTRACTThe effect of processing on the development of internal stresses in spin coated polyimide films was investigated. The internal stresses are a result of the coefficient of thermal expansion (CTE) mismatch between the polymer and the substrate. Birefringence and CTE were used to characterize the in-plane molecular orientation. In-plane orientation was shown to be sensitive to processing conditions. Increasing the spin speed results in higher in-plane orientation as observed by an increase in birefringence and a corresponding decrease in CTE. Heating rate during cure was observed to have a significant effect on in-plane orientation. Faster heating rates during cure resulted in a lower birefringence. The lower birefringence is attributed to relaxation effects that can occur during a rapid cure. The decrease in orientation was accompanied by an increase in internal stress.

Spontaneous Molecular Orientation of Polyimides Induced by Thermal Imidization. 3. Component Chain Orientation in Binary Polyimide Blends

1997 ◽  
Vol 30 (19) ◽  
pp. 5745-5752 ◽  
Author(s):  
Masatoshi Hasegawa ◽  
Kenji Okuda ◽  
Masato Horimoto ◽  
Yoichi Shindo ◽  
Rikio Yokota ◽  
...  
Keyword(s):  
Molecular Orientation ◽  
Chain Orientation ◽  
Thermal Imidization

Spontaneous molecular orientation of polyimides induced by thermal imidization. I. Uniaxial stretching of polyamic acid film

1994 ◽  
Vol 32 (7) ◽  
pp. 1299-1303 ◽  
Author(s):  
Masatoshi Hasegawa ◽  
Yoichi Shindo ◽  
Tokuko Sugimura ◽  
Rikio Yokota ◽  
Masakatsu Kochi ◽  
...  
Keyword(s):  
Molecular Orientation ◽  
Polyamic Acid ◽  
Uniaxial Stretching ◽  
Thermal Imidization

scholarly journals In-Plane Orientation in Poly(amic acid)s during Thermal Imidization

1999 ◽  
Vol 31 (9) ◽  
pp. 707-710 ◽  
Author(s):  
Shin’ya Morino ◽  
Kazuyuki Horie
Keyword(s):  
Amic Acid ◽  
Plane Orientation ◽  
Thermal Imidization

Polarized microbeam FT-IR analysis of single fibers

1996 ◽  
Vol 54 ◽  
pp. 206-207
Author(s):  
Liling Cho ◽  
David L. Wetzel
Keyword(s):  
Molecular Orientation ◽  
Transition Point ◽  
Polymer Fibers ◽  
Single Fiber ◽  
Wire Grid ◽  
Polyester Fibers ◽  
Ft Ir ◽  
Ir Analysis ◽  
The Relationship ◽  
Wire Grid Polarizer

Polarized infrared microscopy has been used for forensic purposes to differentiate among polymer fibers. Dichroism can be used to compare and discriminate between different polyester fibers, including those composed of polyethylene terephthalate that are frequently encountered during criminal casework. In the fiber manufacturering process, fibers are drawn to develop molecular orientation and crystallinity. Macromolecular chains are oriented with respect to the long axis of the fiber. It is desirable to determine the relationship between the molecular orientation and stretching properties. This is particularly useful on a single fiber basis. Polarized spectroscopic differences observed from a single fiber are proposed to reveal the extent of molecular orientation within that single fiber. In the work presented, we compared the dichroic ratio between unstretched and stretched polyester fibers, and the transition point between the two forms of the same fiber. These techniques were applied to different polyester fibers. A fiber stretching device was fabricated for use on the instrument (IRμs, Spectra-Tech) stage. Tension was applied with a micrometer screw until a “neck” was produced in the stretched fiber. Spectra were obtained from an area of 24×48 μm. A wire-grid polarizer was used between the source and the sample.

Sign in / Sign up

Export Citation Format

Share Document