Effect of Different Methods to Synthesize Polyol-Grafted-Cellulose Nanocrystals as Inter-Active Filler in Bio-Based Polyurethane Foams
Abstract
:1. Introduction
2. Materials and Methods
2.1. Materials
2.2. Preparation of Modified CNCs via Freeze-Drying and Solubilization in DMA/LiCl (FD-CNCs)
2.3. Preparation of Modified CNC via Solvent Exchange (SE_CNCs)
2.4. Preparation of Bio-Based PUR Foams
2.4.1. CNCs and Polyols Characterizations
2.4.2. Bio-Based PURs Characterizations
3. Results and Discussions
3.1. Filler Characterization
3.2. Foam Characterization
4. Conclusions
Author Contributions
Funding
Institutional Review Board Statement
Data Availability Statement
Acknowledgments
Conflicts of Interest
References
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Modified-CNCs | Polyol | Modification |
---|---|---|
FD_CNC1 | NX9203 | Freeze drying/Solubilization in DMA/LiCl/Sylanization |
FD_CNC2 | NX9201 | Freeze drying/Solubilization in DMA/LiCl/Sylanization |
SE_CNC1 | NX9203 | Solvent Exchange/Sylanization |
SE_CNC2 | NX9201 | Solvent Exchange/Sylanization |
Components | PUR Pristine (%) | PUR_FD_0 (%) | PUR_SE_0 (%) | PUR_SE_1 (%) | PUR_SE_2 (%) | PUR_FD_1 (%) | PUR_FD_2 (%) |
---|---|---|---|---|---|---|---|
Component A | |||||||
BI6121 | 40.8 | 38.3 | 38.3 | 38.3 | 38.3 | 38.3 | 38.3 |
Niax PM 40 | 0.4 | 0.4 | 0.4 | 0.4 | 0.4 | 0.4 | 0.4 |
CH3COOK | 0.4 | 0.4 | 0.4 | 0.4 | 0.4 | 0.4 | 0.4 |
Niax L6900 | 0.4 | 0.4 | 0.4 | 0.4 | 0.4 | 0.4 | 0.4 |
TCPP | 4 | 4 | 4 | 4 | 4 | 4 | 4 |
H2O | 0.4 | 0.4 | 0.4 | 0.4 | 0.4 | 0.4 | 0.4 |
Filler * | - | 5.1 | 5.1 | 5.1 | 5.1 | 5.1 | 5.1 |
Component B | |||||||
MDI | 53.5 | 51.0 | 51.0 | 51.0 | 51.0 | 51.0 | 51.0 |
Samples | λ (W/mK) |
---|---|
PUR pristine | 0.039 ± 0.002 |
PUR_FD_0 | 0.041 ± 0.005 |
PUR_FD_1 | 0.027 ± 0.007 |
PUR_FD_2 | 0.034 ± 0.009 |
σ (10%) (MPa) | E (MPa) | ρ (kg m−3) | σ (10%)/ρ (MPa/kg m−3) | E/ρ (MPa/kg m−3) | |
---|---|---|---|---|---|
PUR pristine | 0.42 ± 0.03 | 8.03 ± 0.53 | 85.19 ± 3.02 | 4.93 | 94.27 |
PUR_FD_0 | 0.28 ± 0.02 | 3.74 ± 0.16 | 82.57 ± 1.11 | 3.39 | 45.29 |
PUR_FD_1 | 0.70 ± 0.05 | 9.26 ± 0.41 | 94.19 ± 3.97 | 7.43 | 98.31 |
PUR_FD_2 | 0.39 ± 0.04 | 5.77 ± 0.39 | 91.18 ± 4.13 | 4.28 | 63.28 |
Material | E/ES | ρ/ρS | n | C | C’ | φ |
---|---|---|---|---|---|---|
PUR_Pristine | 0.0050 | 0.0710 | 2.0015 | 1.0041 | 0.0707 | 0.9959 |
PUR_FD_0 | 0.0023 | 0.0688 | 2.2637 | 2.0255 | 0.0340 | 0.4937 |
PUR_FD_1 | 0.0058 | 0.0785 | 2.0246 | 1.0646 | 0.0737 | 0.9393 |
PUR_FD_2 | 0.0036 | 0.0760 | 2.1826 | 1.6009 | 0.0475 | 0.6247 |
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Fontana, D.; Recupido, F.; Lama, G.C.; Liu, J.; Boggioni, L.; Silvano, S.; Lavorgna, M.; Verdolotti, L. Effect of Different Methods to Synthesize Polyol-Grafted-Cellulose Nanocrystals as Inter-Active Filler in Bio-Based Polyurethane Foams. Polymers 2023, 15, 923. https://doi.org/10.3390/polym15040923
Fontana D, Recupido F, Lama GC, Liu J, Boggioni L, Silvano S, Lavorgna M, Verdolotti L. Effect of Different Methods to Synthesize Polyol-Grafted-Cellulose Nanocrystals as Inter-Active Filler in Bio-Based Polyurethane Foams. Polymers. 2023; 15(4):923. https://doi.org/10.3390/polym15040923
Chicago/Turabian StyleFontana, Dario, Federica Recupido, Giuseppe Cesare Lama, Jize Liu, Laura Boggioni, Selena Silvano, Marino Lavorgna, and Letizia Verdolotti. 2023. "Effect of Different Methods to Synthesize Polyol-Grafted-Cellulose Nanocrystals as Inter-Active Filler in Bio-Based Polyurethane Foams" Polymers 15, no. 4: 923. https://doi.org/10.3390/polym15040923
APA StyleFontana, D., Recupido, F., Lama, G. C., Liu, J., Boggioni, L., Silvano, S., Lavorgna, M., & Verdolotti, L. (2023). Effect of Different Methods to Synthesize Polyol-Grafted-Cellulose Nanocrystals as Inter-Active Filler in Bio-Based Polyurethane Foams. Polymers, 15(4), 923. https://doi.org/10.3390/polym15040923