Influence of Functionalization Degree on the Rheological Properties of Isocyanate-Functionalized Chitin- and Chitosan-Based Chemical Oleogels for Lubricant Applications
Abstract
:1. Introduction
2. Experimental Section
2.1. Materials
2.2. General Methods
2.3. Functionalization Reaction of Chitosan and Chitin with HMDI
Functionalized Polymer & | Starting material [equiv.] * | HMDI [equiv.] * | Et3N [equiv.] * | Toluene [mL] |
---|---|---|---|---|
CSAN-1 | 1.00 (Chitosan) | 0.50 | 1.00 | 100 |
CSAN-2 | 1.00 (Chitosan) | 0.25 | 0.50 | 100 |
CSAN-3 | 1.00 (Chitosan) | 0.13 | 0.25 | 100 |
CSAN-4 | 1.00 (Chitosan) | 0.06 | 0.13 | 100 |
CTIN-1 | 1.00 (Chitin) | 0.50 | 1.0 | 100 |
CTIN-2 | 1.00 (Chitin) | 0.25 | 0.50 | 100 |
CTIN-3 | 1.00 (Chitin) | 0.13 | 0.25 | 100 |
CTIN-4 | 1.00 (Chitin) | 0.06 | 0.13 | 100 |
2.4. Preparation of Oleogels
2.5. Thermogravimetric Analysis (TGA)
2.6. Fourier Transform Infrared (FTIR) Spectroscopy
Thickener agent | Concentration [%, w/w] | Code Applied * |
---|---|---|
Chitosan | 30 | CSAN-30 |
CSAN-1 | 30 | CSAN-1-30 |
CSAN-2 | 30 | CSAN-2-30 |
CSAN-3 | 30 | CSAN-3-30 |
CSAN-4 | 30 | CSAN-4-30 |
CSAN-3 | 15 | CSAN-3-15 |
CSAN-3 | 25 | CSAN-3-25 |
CSAN-3 | 35 | CSAN-3-35 |
Chitin | 30 | CTIN-30 |
CTIN-1 | 30 | CTIN-1-30 |
CTIN-2 | 30 | CTIN-2-30 |
CTIN-3 | 30 | CTIN-3-30 |
CTIN-4 | 30 | CTIN-4-30 |
CTIN-2 | 15 | CTIN-2-15 |
CTIN-2 | 25 | CTIN-2-25 |
2.7. Rheological Characterization
3. Results and Discussion
3.1. Spectroscopic Characterization
Functional group | Signals | |
---|---|---|
CTIN-1 (cm−1) | CSAN-1 (cm−1) | |
–OH + =NH | 3338 | 3330 |
C–H aliph | 2934 | 2936 |
N=C=O | 2275 | 2271 |
C=O | 1623 | 1741 |
N–H | 1574 | 1580 |
C–N or C–OH | 1259 | 1266 |
C–O or C–OC | 1076 | 1082 |
3.2. Thermogravimetric Characterization
Sample | Tonset [°C] | Tmax [°C] | Tfinal [°C] | ΔW [%] | Residue [%] |
---|---|---|---|---|---|
Chitosan | 281 | 301 | 472 | 57 | 34 |
Chitin | 343 | 389 | 405 | 23 | 72 |
HMDI | 137 | 172 | 178 | 99 | 1 |
CSAN-1 | 122/240/292/429 | 153/258/306/450 | 179/266/340/483 | 44/6/26/9 | 11 |
CSAN-2 | 107/283/431 | 133/306/448 | 150/335/486 | 30/43/9 | 15 |
CSAN-3 | 93/271/391/416 | 129/300/395/443 | 143/324/410/520 | 24/41/3/7 | 25 |
CSAN-4 | 83/274/388/445 | 116/303/401/450 | 133/339/406/464 | 14/51/4/11 | 20 |
CTIN-1 | 93/224/283/361/444 | 135/251/318/393/453 | 154/260/334/414/512 | 34/2/17/25/6 | 16 |
CTIN-2 | 106/275/363/439 | 130/302/389/454 | 140/309/403/494 | 34/10/36/4 | 16 |
CTIN-3 | 83/337/442 | 119/390/459 | 132/411/511 | 22/53/4 | 21 |
CTIN-4 | 83/336/441 | 121/390/463 | 134/411/512 | 22/58/4 | 16 |
Sample | Tonset [°C] | Tmax [°C] | Tfinal [°C] | Residue [%] | ΔW [%] |
---|---|---|---|---|---|
CSAN-30 | 278/357 | 302/389/449 | 319/482 | 4 | 19/77 |
CSAN-1-30 | 297 | 344/386/452 | 481 | 8 | 92 |
CSAN-2-30 | 301 | 339/389/451 | 481 | 10 | 90 |
CSAN-3-30 | 276/353/433 | 307/386/447 | 321/412/483 | 6 | 17/66/11 |
CSAN-4-30 | 266/355 | 302/387/443 | 319/481 | 8 | 26/66 |
CTIN-30 | 340/441 | 381/459 | 409/495 | 11 | 80/9 |
CTIN-1-30 | 324/439 | 379/446 | 410/482 | 3 | 83/14 |
CTIN-2-30 | 327/444 | 376/450 | 405/485 | 5 | 82/13 |
CTIN-3-30 | 326/443 | 374/449 | 406/462 | 6 | 83/11 |
CTIN-4-30 | 328/425 | 373/449 | 404/486 | 4 | 86/10 |
3.3. Rheology of Chitosan- and Chitin-Based Oleogels
4. Conclusions
Acknowledgments
Author Contributions
Conflicts of Interest
References
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Gallego, R.; González, M.; Arteaga, J.F.; Valencia, C.; Franco, J.M. Influence of Functionalization Degree on the Rheological Properties of Isocyanate-Functionalized Chitin- and Chitosan-Based Chemical Oleogels for Lubricant Applications. Polymers 2014, 6, 1929-1947. https://doi.org/10.3390/polym6071929
Gallego R, González M, Arteaga JF, Valencia C, Franco JM. Influence of Functionalization Degree on the Rheological Properties of Isocyanate-Functionalized Chitin- and Chitosan-Based Chemical Oleogels for Lubricant Applications. Polymers. 2014; 6(7):1929-1947. https://doi.org/10.3390/polym6071929
Chicago/Turabian StyleGallego, Rocío, Mercedes González, Jesús F. Arteaga, Concepción Valencia, and José M. Franco. 2014. "Influence of Functionalization Degree on the Rheological Properties of Isocyanate-Functionalized Chitin- and Chitosan-Based Chemical Oleogels for Lubricant Applications" Polymers 6, no. 7: 1929-1947. https://doi.org/10.3390/polym6071929