Letter:
In-Situ X-Ray Analyses of Structural Change During Drawing and Shrinking of Linear Low-Density Polyethylene Film
Hiroaki Yoshizawa*, Ayaka Takazawa*, Masaki Kakiage*, Takeshi Yamanobe*, Naoki Hayashi**, Maki Hiraoka**, Hiroyasu Masunaga***, Kouki Aoyama***, and Hiroki Uehara*
*Division of Molecular Science, Faculty of Science and Technology, Gunma University
1-5-1 Tenjin-cho, Kiryu, Gunma 376-8515, Japan
**Panasonic Corporation
3-1-1 Yagumonakamachi, Moriguchi, Osaka 570-8501, Japan
***Japan Synchrotron Radiation Research Institute (JASRI) / SPring-8
1-1-1 Kouto, Sayo-cho, Sayo-gun, Hyogo 679-5198, Japan
Structural changes during the drawing and shrinking of linear low-density polyethylene (LLDPE) film are analyzed through in-situ X-ray measurements. A synchrotron radiation source enables simultaneous analyses combining small-angle X-ray scattering (SAXS) and wide-angle X-ray diffraction (WAXD). During drawing, the original unoriented SAXS and WAXD patterns transformed into line and spot patterns, indicating the orientation of both lamellar stacking and the molecular axis along the drawing direction. During the subsequent shrinking these patterns are retained, suggesting the tilted lamellar and molecular chains. A possible model for structural changes indicates that tie molecules between lamellae effectively transmit drawing and shrinking stresses, which contributes to desirable actuation properties.
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