2000 Fiscal Year Final Research Report Summary
Dynamics of self-organization in crystalline polymers
| Project/Area Number |
11640378
|
|---|
| Research Category |
Grant-in-Aid for Scientific Research (C)
|
| Allocation Type | Single-year Grants |
|---|
| Section | 一般 |
|---|
| Research Field |
物性一般(含基礎論)
|
|---|
| Research Institution | Hiroshima University |
|---|
Principal Investigator |
TODA Akihiko Hiroshima University, Faculty of Integrated Arts and Sciences, Associate Professor, 総合科学部, 助教授 (70201655)
|
|---|
| Co-Investigator(Kenkyū-buntansha) |
HIKOSAKA Masamichi Hiroshima University, Faculty of Integrated Arts and Sciences, Professor, 総合科学部, 教授 (60087103)
|
|---|
| Project Period (FY) |
1999 – 2000
|
| Keywords | polymer / single crystal / self-organization / higher order structure / banded spherulite / three-dimensional shape |
|---|
| Research Abstract |
We have examined the dynamics of self-organization appearing in the higher order structure of crystalline polymers which is a typical soft-condensed matter. Crystallization of polymers organizes complex and various structures which cannot be formed by small molecules. As a typical example, it is well known that a periodic pattern of concentric banding is formed during the crystallization of polymer spherulite from the melt. In the present research, utilizing the observation by transmission electron microscopy, we have clarified the physical mechanism of twist in the lamellar crystallites of polymer, which is the basic structure producing the periodic pattern. We have examined the morphology of poly (vinylidene fluoride) (PVDF) single crystals grown from the melt and from the blend with poly (ethyl acrylate) (PEA) : PVDF/PEA = 0.5/99.5 and 30/70 by weight ratio. Three-dimensional morphology of single crystals was examined by transmission electron microscopy (bright field, dark field and diffraction) with a tilting stage. For all cases, the titling of chains by 26 degrees to the fold surface has been confirmed. Three-dimensional shape of all crystals was chair type for 30/70 blend and pure PVDF.In chair crystals, spiral terraces keep the handedness in each growth direction. From those evidences, we have proposed that the chair crystals with consecutive creation of spiral terraces of the same sense are responsible for the twisting relationship between crystallites in the radial direction of banded spherulites. Based on this conclusion, we have confirmed the consistence in the handedness of twisting in the banded spherulites by the observation with atomic force microscopy.
|
Research Products
(24 results)
