AI Article Synopsis
- Developing new polymer chemistries for on-demand controlled depolymerization can enhance various scientific and industrial applications.
- Functionalized poly(caprolactone)s (PCLs) with protected amino groups are engineered to allow complete depolymerization upon activation, leading to specific cyclic products.
- Experiments with two different protecting groups confirmed that PCL can degrade rapidly and effectively, demonstrating a promising method for speeding up polymer breakdown and improving safety in applications involving nanoparticles.
Article Abstract
Developing polymer chemistries capable of on-demand, controlled depolymerization is an important tool in a broad variety of applications in science, technology, and industry. We report functionalized poly(caprolactone)s (PCL)s designed to allow on-demand and complete depolymerization through incorporation of pendant protected amino groups that, on deprotection, trigger nucleophilic attack and yield a single cyclic product. Two cleavable protecting groups were used to cap PCL: light sensititve -nitrobenzyl alcohol (ONB) and tert-butyl carbamate (Boc) (for proof of concept). NMR confirmed that PCL-Boc degrades completely into the designed intramolecular cyclization products within a day upon deprotection. TEM visualization of particles made from PCL-ONB encapsulating iron oxide nanoparticles reveals complete disruption of nanoparticles and release of payload. This work demonstrates that intramolecular cyclization within the polymer backbone is an excellent route to accelerate polymer degradation by backbiting reactions into small fragments that should be easily cleared from the circulation.
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| http://www.ncbi.nlm.nih.gov/pmc/articles/PMC3694623 | PMC |
| http://dx.doi.org/10.1021/mz400129h | DOI Listing |
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