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Monitoring the Effects of Illumination on the Structure of Conjugated Polymer Gels Using Neutron Scattering
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Phase-Separated Structure of NBR/PVC Blends with Different Acrylonitrile Contents Investigated Using STEM-EDS Mapping
Yuka Komori1,2, Aoi Taniguchi2, Haruhisa Shibata1
1Materials Engineering R & D Division, DENSO CORPORATION, Kariya-shi 448-8661, Aichi, Japan.
Polymers
|August 26, 2023
Summary
This study examined nitrile butadiene rubber/polyvinyl chloride blends. Higher acrylonitrile content increased blend miscibility, altering phase separation structures.
Area of Science:
- Polymer Science
- Materials Science
- Physical Chemistry
Background:
- Nitrile butadiene rubber (NBR) and polyvinyl chloride (PVC) blends are widely used.
- Understanding their phase-separated structure is crucial for tailoring material properties.
- The influence of acrylonitrile (AN) content in NBR on blend morphology requires detailed investigation.
Purpose of the Study:
- To investigate the phase-separated structure of NBR/PVC blends with varying AN content in NBR.
- To correlate miscibility changes with AN content using dynamic mechanical analysis and microscopy.
- To analyze the domain morphology and component distribution within the blends.
Main Methods:
- Dynamic mechanical analysis (DMA) to measure tan delta peaks.
- Scanning-transmission-electron-microscopy (STEM) coupled with energy-dispersive-X-ray-spectroscopy (EDS) for elemental analysis.
- Characterization of phase separation and component distribution.
Main Results:
- Two distinct tan delta peaks at low AN content (18.0%) indicated significant phase separation.
- A single broad tan delta peak at higher AN contents (29.0% and 33.5%) suggested increased miscibility.
- STEM-EDS revealed large PVC domains at low AN content and nanoscale dispersed domains at higher AN content.
- Increasing AN content reduced the concentration difference between PVC domains and the NBR matrix.
Conclusions:
- Higher AN content in NBR enhances miscibility in NBR/PVC blends.
- AN content significantly influences the phase-separated morphology and component distribution.
- The observed changes in mechanical properties and morphology are consistent with increased polymer blend miscibility.
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