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Multiscale Relaxation Behavior of Amorphous Plasticized Poly(vinyl butyral)
Changzhu Lv1,2, Hang Guo1,2, Erjie Yang1,2
1National Synchrotron Radiation Laboratory, University of Science and Technology of China, Hefei, 230026, China.
Macromolecular Rapid Communications
|June 21, 2023
Summary
Plasticized polyvinyl butyral (PVB) exhibits stretch-induced phase separation. This study investigates its multiscale relaxation behavior using ultrasmall angle X-ray scattering (USAXS) and birefringence, revealing contributions from chain segments and hydrogen bonds.
Area of Science:
- Materials Science
- Polymer Physics
- Nanotechnology
Background:
- Plasticized polyvinyl butyral (PVB) is a crucial impact-resistant polymer in laminated glass.
- Recent studies revealed stretch-induced phase separation in PVB at the nanoscale using ultrasmall angle X-ray scattering (USAXS).
- Understanding the relaxation behavior of PVB is essential for optimizing its performance.
Purpose of the Study:
- To investigate the multiscale relaxation behavior of plasticized PVB under deformation.
- To explore the relationship between macroscopic stress, mesoscopic structure, and microscopic chain dynamics.
- To elucidate the roles of chain segments and hydrogen bonding clusters in PVB relaxation.
Main Methods:
- Combined ultrasmall angle X-ray scattering (USAXS) and birefringence measurements.
- Utilized an in situ stretching device to study deformation dynamics.
- Analyzed relaxation behavior across macroscopic, mesoscopic, and microscopic scales.
Main Results:
- Observed and characterized multiscale relaxation phenomena in deformed plasticized PVB.
- Demonstrated the formation of stretch-induced phase-separated structures at the nanoscale.
- Identified contributions from both polymer chain segments and hydrogen bonding clusters to the relaxation process.
Conclusions:
- The multiscale relaxation behavior of plasticized PVB is complex, involving contributions from different structural levels.
- USAXS and birefringence are effective techniques for probing these phenomena.
- Understanding these relaxation mechanisms is key for designing advanced PVB materials for laminated glass applications.
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