Thermoresponsive Core-Shell Nanoparticles: Does Core Size Matter?
Abstract
:1. Introduction
2. Materials and Methods
2.1. Materials
2.2. Methods
3. Results and Discussion
3.1. Preparation and Characterization of the Core-Shell Nanoparticles
3.2. Temperature Dependence of Aggregation: Free Polymer versus Core-Shell Nanoparticles
3.3. Critical Solution Temperature and Transition Enthalpies of Polymer Grafted to Nanoparticles
3.4. Is the Aggregation of the Thermoresponsive Core-Shell Nanoparticles Fully Reversible?
3.5. Does the Curvature Influence on Internal Brush Structure Affect the CST of the Polymer Shell?
3.6. Does Nanoparticle Concentration Influence Brush CST and Thermally Induced Aggregation?
4. Conclusions
Supplementary Materials
Author Contributions
Funding
Acknowledgments
Conflicts of Interest
References
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Sample | Core-shell Particle Concentration (g L−1) | Grafted Polymer Concentration (g L−1) | Particle Molarity (mol L−1) |
---|---|---|---|
FeOx-5 | 0.07 | 0.06 | 2.7 × 10−8 |
FeOx-5 | 0.1088 | 0.1 | 4.0 × 10−9 |
FeOx-5 | 0.54 | 0.5 | 2.0 × 10−7 |
FeOx-5 | 1.088 | 1.0 | 4.0 × 10−7 |
FeOx-5 | 10.88 | 10 | 4.0 × 10−6 |
FeOx-7 | 0.114 | 0.1 | 2.2 × 10−8 |
FeOx-7 | 0.135 | 1.12 | 2.7 × 10−8 |
FeOx-7 | 0.57 | 0.5 | 1.1 × 10−7 |
FeOx-7 | 1.14 | 1.0 | 2.2 × 10−7 |
FeOx-7 | 11.4 | 10 | 2.2 × 10−6 |
FeOx-10 | 0.116 | 0.1 | 9.3 × 10−9 |
FeOx-10 | 0.324 | 0.28 | 2.7 × 10−9 |
FeOx-10 | 0.58 | 0.5 | 4.7 × 10−8 |
FeOx-10 | 1.16 | 1.0 | 9.3 × 10−8 |
FeOx-10 | 11.6 | 10 | 9.3 × 10−7 |
FeOx-21 | 0.139 | 0.1 | 2.7 × 10−9 |
FeOx-21 | 0.695 | 0.5 | 1.3 × 10−8 |
FeOx-21 | 1.39 | 1.0 | 2.7 × 10−8 |
FeOx-21 | 13.9 | 10 | 2.7 × 10−7 |
Sample | Core Diameter (nm) | TGA | |||
---|---|---|---|---|---|
Weight Loss (wt %) | Residue (wt %) | ||||
FeOx-5 | 5.1 ± 0.6 | 91.9 | 8.1 | 1.2 | 19.7 ± 4.9 |
FeOx-7 | 7.4 ± 0.5 | 87.3 | 12.7 | 1.0 | 21.4 ± 1.1 |
FeOx-10 | 10.2 ± 0.7 | 86.1 | 13.9 | 1.3 | 21.6 ± 1.6 |
FeOx-21 | 20.9 ± 1.3 | 72.1 | 27.9 | 1.1 | 30.5 ± 1.9 |
Sample | CFT (°C) | ||
---|---|---|---|
Free Polymer | 108.7 ± 5.0 | 1340.9 ± 25.1 | 38 |
FeOx-5 | 19.7 ± 1.0 | 91.7 ± 1.0 | 34 |
FeOx-7 | 21.4 ± 0.7 | 80.9 ± 0.4 | 34 |
FeOx-10 | 20.0 ± 0.3 | 65.5 ± 0.3 | 34 |
FeOx-21 | 30.5 ± 0.4 | 97.7 ± 0.5 | 33 |
Sample | Grafted Polymer Concentration (g L−1) | |||
---|---|---|---|---|
FeOx-5 | 0.06 | 3.85 | −3.16 | 82 |
FeOx-5 | 0.1 | 4.13 | −2.29 | 55 |
FeOx-5 | 0.5 | 3.86 | −2.65 | 69 |
FeOx-5 | 1.0 | 3.97 | −2.88 | 72 |
FeOx-5 | 10 | 4.05 | −3.71 | 92 |
FeOx-5 mean | 3.97 ± 0.11 | −2.94 ± 0.48 | 74 | |
FeOx-7 | 0.1 | 3.75 | −2.71 | 72 |
FeOx-7 | 0.12 | 3.76 | −2.89 | 77 |
FeOx-7 | 0.5 | 3.85 | −2.68 | 69 |
FeOx-7 | 1.0 | 3.80 | −3.33 | 88 |
FeOx-7 | 10 | 3.73 | −3.26 | 88 |
FeOx-7 mean | 3.78 ± 0.05 | −2.97 ± 0.27 | 79 | |
FeOx-10 | 0.1 | 3.47 | −1.66 | 48 |
FeOx-10 | 0.28 | 3.40 | −2.35 | 69 |
FeOx-10 | 0.5 | 3.30 | −2.37 | 72 |
FeOx-10 | 1.0 | 3.33 | −2.37 | 71 |
FeOx-10 | 10 | 3.53 | −3.08 | 87 |
FeOx-10 mean | 3.41 ± 0.09 | −2.37 ± 0.45 | 69 | |
FeOx-21 | 0.1 | 3.64 | −1.78 | 49 |
FeOx-21 | 0.5 | 3.70 | −2.00 | 54 |
FeOx-21 | 1.0 | 3.67 | −2.55 | 69 |
FeOx-21 | 10 | 3.58 | −3.23 | 90 |
FeOx-21 mean | 3.65 ± 0.04 | −2.39 ± 0.56 | 65 | |
Free polymer | 0.1 | 4.46 | −1.75 | 39 |
Free polymer | 0.5 | 4.76 | −2.66 | 56 |
Free polymer | 1 | 4.85 | −5.06 | 104 |
Free polymer | 10 | 4.81 | −3.04 | 63 |
Free polymer mean | 4.72 ± 0.15 | −3.13 ± 1.21 | 66 |
Sample | ||
---|---|---|
FeOx-5 | 19.7 ± 1.0 | 23.4 ± 0.7 |
FeOx-7 | 21.4 ± 0.7 | 25.5 ± 0.5 |
FeOx-10 | 20.0 ± 0.3 | 23.1 ± 0.6 |
FeOx-21 | 30.5 ± 0.4 | 33.9 ± 0.4 |
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Schroffenegger, M.; Reimhult, E. Thermoresponsive Core-Shell Nanoparticles: Does Core Size Matter? Materials 2018, 11, 1654. https://doi.org/10.3390/ma11091654
Schroffenegger M, Reimhult E. Thermoresponsive Core-Shell Nanoparticles: Does Core Size Matter? Materials. 2018; 11(9):1654. https://doi.org/10.3390/ma11091654
Chicago/Turabian StyleSchroffenegger, Martina, and Erik Reimhult. 2018. "Thermoresponsive Core-Shell Nanoparticles: Does Core Size Matter?" Materials 11, no. 9: 1654. https://doi.org/10.3390/ma11091654
APA StyleSchroffenegger, M., & Reimhult, E. (2018). Thermoresponsive Core-Shell Nanoparticles: Does Core Size Matter? Materials, 11(9), 1654. https://doi.org/10.3390/ma11091654