Abstract
Relations between molecular design, chemical functionality, and stimulus-triggered response are important for a variety of applications of polymeric systems. Here, reactive amphiphilic block copolymers (BCPs) of poly(2-vinylpyridine)-block-poly(2-vinyl-4,4-dimethylazlactone) (PVP-b-PVDMA) were synthesized and assembled into microgels capable of incorporating functional amines. The composition of the PVP-b-PVDMA BCPs was varied to control the number of reactive sites in the spherical aggregates created by self-assembly of PVP-b-PVDMA BCPs in a 2-propanol/THF (v:v = 19:1) solvent mixture, which is selective for PVP. PVDMA and PVP segments were selectively cross-linked by 1,4-diaminobutane (DAB) or 1,4-diiodobutane (DIB) to fabricate core- and corona-cross-linked azlactone-containing microgels, respectively. Non-cross-linked aggregates of PVP-b-PVDMA and DIB-cross-linked microgels dissociate when exposed to THF, which is a good solvent for both blocks. However, the DAB-cross-linked BCP microgels swell in THF, suggesting the formation of a stable, three-dimensional network structure. Because of their ability to be reactively modified in ways that allows their stability or disassembly characteristics to be tailored, these azlactone-containing BCP microgels provide an attractive platform for applications in a wide range of fields, including catalysis, imaging, molecule separation, and guest loading for targeted delivery.
| Original language | English |
|---|---|
| Pages (from-to) | 3691-3701 |
| Number of pages | 11 |
| Journal | Macromolecules |
| Volume | 51 |
| Issue number | 10 |
| DOIs | |
| State | Published - May 22 2018 |
Funding
This research was supported in part by the National Science Foundation (Award Nos. 1131252 and 1512221) (S.M.K.II, B.A., J.D.), the Program of Qilu Young Scholars of Shandong University (X.W.), and National Natural Science Foundation of China (NSFC grant 21704057) (X.W.). A portion of this research was conducted at the Center for Nanophase Materials Sciences, which is a DOE Office of Science User Facility. Prof. Robert N. Compton, Dr. Mohammadreza Rezaee, and Dr. Weikun Li are gratefully acknowledged for assistance with photoisomerization studies, and Dr. Zhenqian Zhu is thanked for assistance with mass spectroscopy measurements. Prof. Brian Long is thanked for the helpful discussions, as are Prof. Wenshou Wang and Zongpeng Gao for their assistance with XPS studies.