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Abstract Ionic liquids (ILs) have emerged as promising biomaterials for enhancing drug delivery by functionalizing polymeric nanoparticles (NPs). Despite the biocompatibility and biofunctionalization they confer upon the NPs, little is understood regarding the degree in which non‐covalent interactions, particularly hydrogen bonding and electrostatic interactions, govern IL‐NP supramolecular assembly. Herein, we use salt (0‐1 M sodium sulfate) and acid (0.25 M hydrochloric acid at pH 4.8) titrations to disrupt IL‐functionalized nanoassembly for four different polymeric platforms during synthesis. Through quantitative1H‐nuclear magnetic resonance spectroscopy and dynamic light scattering, we demonstrate that the driving force of choline trans‐2‐hexenoate (CA2HA 1:1) IL assembly varies with either hydrogen bonding or electrostatics dominating, depending on the structure of the polymeric platform. In particular, the covalently bound or branched 50:50 block co‐polymer systems (diblock PEG‐PLGA [DPP] and polycaprolactone [PCl]‐poly[amidoamine] amine‐based linear‐dendritic block co‐polymer) are predominantly affected by hydrogen bonding disruption. In contrast, a purely linear block co‐polymer system (carboxylic acid terminated poly[lactic‐co‐glycolic acid]) necessitates both electrostatics and hydrogen bonding to assemble with IL and a two‐component electrostatically bound system (electrostatic PEG‐PLGA [EPP]) favors hydrogen‐bonding with electrostatics serving as a secondary role.
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Thermodynamics and Structure–Property Relationships of Charged Block Polymers
Abstract Advancements in electronics and energy storage and conversion technologies brings with it myriads of exciting material design challenges. Charge‐containing block polymers (BPs) offer unique features which can overcome some of these challenges and have thus aroused substantial interest within the field of designer soft materials. The properties of BPs are intricately coupled to the dynamic and rich nature of the nanostructured assemblies, which result from the phase separation between blocks. The introduction of strong secondary forces, such as electrostatics and hydrogen bonding (H‐bonding), into BPs greatly influences their self‐assembly behavior, and therefore affects their physical and electrochemical properties often in nontrivial ways. In this review, some of the prevailing research, which has expanded the understanding of structure–property relationships to include several design strategies for improving ionic conductivity and modulus in charged block polymers, is presented. The profound extent to which electrostatics and hydrogen bonding impact block polymer thermodynamics, an extent which is demonstrated by recent theoretical and experimental work, is also highlight. Insights gained from the research presented here help to lay the groundwork for a long and bright future in the field of advanced soft materials.
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- Award ID(s):
- 1848454
- PAR ID:
- 10445098
- Publisher / Repository:
- Wiley Blackwell (John Wiley & Sons)
- Date Published:
- Journal Name:
- Macromolecular Chemistry and Physics
- Volume:
- 223
- Issue:
- 14
- ISSN:
- 1022-1352
- Format(s):
- Medium: X
- Sponsoring Org:
- National Science Foundation
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