We report tert-butoxycarbonyl (t-BOC) is a thermally labile moiety that can be used to protect hydroxyl groups on polymers. In this study, t-BOC was appended onto a polyimide consisting of 2,2'-bis-(3,4-dicarboxyphenyl) hexafluoropropane dianhydride (6FDA) and 3,3'-dihydroxy-4,4'-diamino-biphenyl (HAB), after which the polymer was formed into self-standing films. Solid-state thermal treatments were performed to systematically remove t-BOC moieties to alter the physical packing structure and concomitant gas transport properties of the polymer. Despite performing deprotection reactions well below the glass transition temperature of 6FDA-HAB (~300 °C), this free volume manipulation (FVM) approach produced only subtle differences in polymer density, fractional free volume, average free volume element size, and gas transport properties relative to the unprotected polymer. While these findings suggest that thermally removing covalently bound functional groups from polymer films can be used to manipulate free volume and gas transport performance for glassy polymers, more robust polymer systems than linear polyimides are required to preserve the nascent free volume architecture generated from this approach.
Lin, Sharon, et al. "Free volume manipulation of a 6FDA-HAB polyimide using a solid-state protection/deprotection strategy." Polymer, vol. 212, no. C, Oct. 2020. https://doi.org/10.1016/j.polymer.2020.123121
Lin, Sharon, Joo, Taigyu, Benedetti, Francesco M., Chen, Laura C., Wu, Albert X., Mizrahi Rodriguez, Katherine, Qian, Qihui, Doherty, Cara M., & Smith, Zachary P. (2020). Free volume manipulation of a 6FDA-HAB polyimide using a solid-state protection/deprotection strategy. Polymer, 212(C). https://doi.org/10.1016/j.polymer.2020.123121
Lin, Sharon, Joo, Taigyu, Benedetti, Francesco M., et al., "Free volume manipulation of a 6FDA-HAB polyimide using a solid-state protection/deprotection strategy," Polymer 212, no. C (2020), https://doi.org/10.1016/j.polymer.2020.123121
@article{osti_1852807,
author = {Lin, Sharon and Joo, Taigyu and Benedetti, Francesco M. and Chen, Laura C. and Wu, Albert X. and Mizrahi Rodriguez, Katherine and Qian, Qihui and Doherty, Cara M. and Smith, Zachary P.},
title = {Free volume manipulation of a 6FDA-HAB polyimide using a solid-state protection/deprotection strategy},
annote = {We report tert-butoxycarbonyl (t-BOC) is a thermally labile moiety that can be used to protect hydroxyl groups on polymers. In this study, t-BOC was appended onto a polyimide consisting of 2,2'-bis-(3,4-dicarboxyphenyl) hexafluoropropane dianhydride (6FDA) and 3,3'-dihydroxy-4,4'-diamino-biphenyl (HAB), after which the polymer was formed into self-standing films. Solid-state thermal treatments were performed to systematically remove t-BOC moieties to alter the physical packing structure and concomitant gas transport properties of the polymer. Despite performing deprotection reactions well below the glass transition temperature of 6FDA-HAB (~300 °C), this free volume manipulation (FVM) approach produced only subtle differences in polymer density, fractional free volume, average free volume element size, and gas transport properties relative to the unprotected polymer. While these findings suggest that thermally removing covalently bound functional groups from polymer films can be used to manipulate free volume and gas transport performance for glassy polymers, more robust polymer systems than linear polyimides are required to preserve the nascent free volume architecture generated from this approach.},
doi = {10.1016/j.polymer.2020.123121},
url = {https://www.osti.gov/biblio/1852807},
journal = {Polymer},
issn = {ISSN 0032-3861},
number = {C},
volume = {212},
place = {United States},
publisher = {Elsevier},
year = {2020},
month = {10}}
Massachusetts Inst. of Technology (MIT), Cambridge, MA (United States)
Sponsoring Organization:
USDOE Office of Science (SC), Basic Energy Sciences (BES); Society of Energy Fellows at MIT; National Science Foundation (NSF); National Academies of Science Engineering and Medicine
Nuclear Instruments and Methods in Physics Research Section A: Accelerators, Spectrometers, Detectors and Associated Equipment, Vol. 374, Issue 2https://doi.org/10.1016/0168-9002(96)00075-7