| Project/Area Number |
15550109
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| Research Category |
Grant-in-Aid for Scientific Research (C)
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| Allocation Type | Single-year Grants |
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| Section | 一般 |
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| Research Field |
Polymer chemistry
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| Research Institution | Japan Synchrotron Radiation Research Institute (JASRI/SPring-8) (2004-2005)
Kyushu University (2003) |
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Principal Investigator |
SASAKI Sono Japan Synchrotron Radiation Research Institute, Materials Structure Group I, Researcher, 利用研究促進部門・動的構造チーム, 副主幹研究員 (40304745)
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| Co-Investigator(Kenkyū-buntansha) |
KIKUCHI Hirotsugu Kyusyu University, Institute for Materials Chemistry and Engineering, Professor, 先導物質化学研究所 融合材料部門, 教授 (50186201)
TANAKA Keiji Kyusyu University, Graduate School of Engineering, Associate Professor, 大学院・工学研究院, 助教授 (20325509)
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| Project Period (FY) |
2003 – 2005
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| Project Status |
Completed (Fiscal Year 2005)
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| Budget Amount *help |
¥3,700,000 (Direct Cost: ¥3,700,000)
Fiscal Year 2005: ¥800,000 (Direct Cost: ¥800,000)
Fiscal Year 2004: ¥900,000 (Direct Cost: ¥900,000)
Fiscal Year 2003: ¥2,000,000 (Direct Cost: ¥2,000,000)
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| Keywords | Crystallization polymer films / SR-GIXD method / SR-GISAXS method / SPring-8, the large synchrotron radiation facility / Paracrystalline lattice distortion / Lamellar stacking structure / Higher-order structure / Annealing Effect / SR-GISAXS法 / 高密度ポリエチレン / 放射光視斜角入射X線回折(SR-GIXD)法 / 結晶構造 / 高分子-基板間の熱応力 / 結晶性高分子固体表面構造解析 / ポリエチレン / 視斜角入射X線回折(GIXD)法 / 放射光X線回折 / パラクリスタル解析 |
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| Research Abstract |
We have successfully investigated chain and lamellar packing structures peculiar to crystalline polymers confined to narrow space, such as the surface and the thin film, by synchrotron grazing-incidence X-ray diffraction (SR-GIXD) and grazing-incidence small-angle X-ray scattering (SR-GISAXS) measurements. Thin films with a thickness of ca. 400 nm were prepared on silicon wafers from a p-xylene solution of high-density polyethylene (HDPE) by a dip-coating method. The dip-coated films and HDPE bulk samples were isothermally crystallized from the melt or annealed at various temperatures under nitrogen atmosphere.
In order to detect Bragg diffractions from the near-surface and bulk regions of the thin films, in-plane GIXD measurements were carried out at incident angles (α_i) of X-rays smaller and lager than the critical angle (α_c) at the BL13XU beamline of SPring-8 (Hyogo, Japan). It was revealed that the lattice constants a and b of orthorhombic unit cell in the near-surface region of t
… More
he thin film were smaller than those in the bulk region but larger than those of the bulk samples. This implied that the unit cell especially in the interfacial region between PE and silicon was distorted during sample preparation due to large mismatching between their thermal expansion coefficients. On the other hand, pracrystalline lattice analysis for the thin films indicated that long and short-range lattice distortion was larger in the near-surface region than in the bulk region. This might be related with the surface free energy of the film and/or releasing the latent heat from the surface.
SR-GISAXS measurements were carried out at α_i of X-rays smaller and lager than the α_c at the BL40B2 beamline of SPring-8. The 2D-GISAXS patterns from the films placed in a vacuum cell were detected at 300K with an imaging intensifier and a CCD detector or an imaging plate. Strong scattering in the in-plane direction near Yoneda peak were detected for all of the films. From the peak position of the scattering, it was found that the long period, the average distance between stacked crystalline lamellae, was ca.25-30 nm. From the GIXD data, it was implied that chains were relatively oriented parallel to the surface in the lamellae. Combination of GIXD and GISAXS data indicated that relatively edge-on oriented lamellae were stacked in the parallel direction to the surface. By annealing, partial melting and recrystallization might occur remarkably in the near-surface region. Less
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