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  • Bottlebrush Elastomers with Crystallizable Side Chains: Monitoring Configuration of Polymer Backbones in the Amorphous Regions during Crystallization
Title: Bottlebrush Elastomers with Crystallizable Side Chains: Monitoring Configuration of Polymer Backbones in the Amorphous Regions during Crystallization
Brush-like elastomers with crystallizable side chains hold promise for biomedical applications requiring the presence of two distinct mechanical states below and above body temperature: hard and supersoft. The hard semicrystalline state facilitates piercing of the body whereupon the material softens to match the mechanics of surrounding soft tissue. To understand the transition between the two states, the crystallization process was studied with synchrotron X-ray scattering for a series of brush elastomers with poly(ε-caprolactone) side chains bearing from 7 to 13 repeat units. The so-called bottlebrush correlation peak was used to monitor configuration of bottlebrush backbones in the amorphous regions during the crystallization process. In the course of crystallization, the backbones are expelled into the interlamellar amorphous gaps, which is accompanied by their conformational changes and leads to partitioning to unconfined (melt) and confined (semicrystalline) (conformational) states. The crystallization process starts by consumption of the unconfined macromolecules by the growing crystals followed by reconfiguration of macromolecules within the already grown spherulites.  more » « less
Award ID(s):
1921835 2004048
PAR ID:
10355318
Author(s) / Creator(s):
; ; ; ;
Date Published:
Journal Name:
ACS Macro Letters
Volume:
11
ISSN:
2161-1653
Page Range / eLocation ID:
1085 to 1090
Format(s):
Medium: X
Sponsoring Org:
National Science Foundation
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