1991 Fiscal Year Final Research Report Summary
Polymer Dynamics Studies with Flow Birefringence Method
| Project/Area Number |
02453101
|
|---|
| Research Category |
Grant-in-Aid for General Scientific Research (B)
|
| Allocation Type | Single-year Grants |
|---|
| Research Field |
高分子物性・高分子材料（含機械材料）
|
|---|
| Research Institution | Kyoto University |
|---|
Principal Investigator |
OSAKI Kunihiro Kyoto University, Institute for Chemical Research, Professor, 化学研究所, 教授 (00027046)
|
|---|
| Co-Investigator(Kenkyū-buntansha) |
INOUE Tadashi Kyoto University, Institute for Chemical Research, Instructor, 化学研究所, 助手 (80201937)
NEMOTO Norio Kyoto University, Institute for Chemical Research, Associate Professor, 化学研究所, 助教授 (90027053)
|
|---|
| Project Period (FY) |
1990 – 1991
|
| Keywords | Flow Birefringence / Stress-Optical Rule / Glassy Polymer / Glass Transition / Stress Relaxation / Viscoelasticity / Polystyrene / Polycarbonate |
|---|
| Research Abstract |
(1) An optical system was equipped to a tensile tester for simultaneous measurements of stress and birefringence of a polymeric film. The range of time for relaxation measurement was 1 - 10^4s and the range of temperature was 0 - 200ﾟC. An apparatus for simultaneous measurements of viscoelasticity and dynamic birefringence was developed by adding an optical system to a dynamic rheometer. The frequency range was 1 - 20OHz and the temperature range was 0 - 250 ﾟC.
(2) A modified stress-optical rule was proposed to describe the stress and birefringence of amorphous polymers. The method was applied to polystyrene, poly- alpha -methylstyrene, polyarylate, polycarbonate, polysulfone, polyethersulfone, polyetherimide, and polyetherether ketone. For these polymers, the viscoelastic relaxation spectrum was revealed to consist of two components. The difference in temperature dependence of these components was revealed to be the origin of the complicated temperature dependence of viscoelasticity around the glass transition point.
(3) The stress and birefringence were measured after an instantaneous large deformation and during a deformation at constant speed for polystyrene and polycarbonate. The yield phenomenon of such a glassy polymer was revealed to represent the yield of the enthalpic force due to the potential energy. The entropic force did not show any sign of yield phenomenon.
|
