Characterization of the Low Molar Ratio Urea–Formaldehyde Resin with 13C NMR and ESI–MS: Negative Effects of the Post-Added Urea on the Urea–Formaldehyde Polymers
Abstract
:1. Introduction
2. Experimental
2.1. UF Resin Sample Preparation
2.2. Procedure for Quantitative 13C-NMR Determination
2.3. Procedure for ESI-MS Spectrometry
3. Results and Discussion
3.1. 13C NMR Results
3.2. ESI-MS Spectra
3.3. A Proposed Alternative to Post-Added Urea
4. Conclusions
Author Contributions
Acknowledgments
Conflicts of Interest
References
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Structure | Chemical Shift (ppm) | UF-1 | UF-2 | UF-3 | UF-4 | UF-5 |
---|---|---|---|---|---|---|
–NH–CH2–NH–(I) | 46–47 | - | 4.89 | 7.57 | 10.82 | 15.16 |
–NH–CH2–N=(II) | 53–54 | - | 3.48 | 8.03 | 23.76 | 16.10 |
=N–CH2–N=(III) | 60–61 | - | - | - | 0.68 | - |
Total | - | 8.37 | 15.60 | 35.26 | 31.26 | |
–NH–CH2OCH2NH–(I) | 68–69 | 18.26 | 20.31 | 18.61 | 10.74 | 10.69 |
–NH–CH2OCH2N=(II)/uron | 75–76 | 2.38 | 2.42 | 3.05 | 1.40 | 2.40 |
=N–CH2OCH2N=(III)/uron | 78–80 | 6.71 | 7.32 | 8.13 | 9.98 | 4.14 |
Total | 27.35 | 30.05 | 29.79 | 22.12 | 17.23 | |
–NH–CH2OH(I) | 64–65 | 55.63 | 39.81 | 31.32 | 16.37 | 46.59 |
–NH(–CH2)–CH2OH(II) | 70–71 | 9.04 | 9.72 | 11.03 | 13.94 | 1.82 |
Total | 64.67 | 49.53 | 42.35 | 30.31 | 48.41 | |
HO–CH2–OH | 83–84 | 1.13 | 1.57 | 1.93 | 3.99 | 0.24 |
HOCH2–O–CH2–OCH2OH | 86–87 | 1.84 | 1.54 | 1.99 | 3.00 | 0.30 |
HOCH2–O–CH2–OCH2OH | 90–91 | 2.43 | 1.26 | 1.53 | 2.20 | 0.21 |
H(CH2O)nOCH2OCH3 | 94–95 | 0.48 | 0.39 | 0.31 | - | - |
Total | 5.88 | 4.76 | 5.76 | 9.19 | 0.75 | |
–NH–CH2–O–CH3 | 72–73 | 2.11 | 7.27 | 6.51 | 3.12 | 2.35 |
NH2–CO–NH2 | 162–163 | 4.29 | 1.31 | 0.48 | - | 19.94 |
NH2–CO–NH– | 160–162 | 33.74 | 29.85 | 15.52 | 4.42 | 38.52 |
–NH–CO–N–/–NH–CO–N= | 159–160 | 54.55 | 61.38 | 76.46 | 88.22 | 38.47 |
Uron | 153–158 | 7.42 | 7.46 | 7.54 | 7.36 | 3.07 |
m/z | Structure | m/z | Structure |
---|---|---|---|
113 | U–CH2OH (Na+) | 275 | HOCH2–U–CH2O–CH2–U–(CH2OH)2 (Na+) |
127 | U–CH2OH (H+)…2H2O | 289 | Uron–CH2–O–CH2–U–CH2OH (K+) |
143 | HOCH2–U–CH2OH (Na+) | 305 | (HOCH2)2–U–CH2O–CH2–U–(CH2OH)2 (Na+) |
157 | CH2OH–U–CH2OH (H+)…2H2O | 319 | Uron-CH2–O–CH2–U–(CH2OH)2 (K+) |
173 | HOCH2–U–(CH2OH)2 (Na+) | 335 | (HOCH2)2–U–CH2O–CH2–U–(CH2OH)–CH2–O–CH2OH (Na+) |
187 | CH2OH–U–(CH2OH)2 (H+)…2H2O | 347 | (HOCH2)2–U–CH2O–CH2–U–CH2–O–CH2–U (Na+) |
203 | HOCH2–U–CH2OH (Na+)…U | 361 | Uron–CH2–O–CH2–U–CH2–O–CH2–U (K+) |
215 | HOCH2–U–CH2O–CH2–U (Na+) | 377 | (HOCH2)2–U–CH2O–CH2–U–CH2–O–CH2–U–CH2OH (Na+) |
231 | HOCH2–U–CH2O–CH2–U (K+) | 391 | Uron–CH2–O–CH2–U–CH2–O–CH2–U–CH2OH (K+) |
245 | HOCH2–U–CH2O-CH2–U–CH2OH (Na+) | 407 | (HOCH2)2–U–CH2O–CH2–U–CH2–O–CH2–U–(CH2OH)2 (Na+) |
259 | Uron–CH2–O–CH2–U (K+) | 421 | Uron–CH2–O–CH2–U–CH2–O–CH2–U–(CH2OH)2 (K+) |
m/z | Structure | m/z | Structure |
---|---|---|---|
143 | CH2OH–U–CH2OH (Na+) | 361 | HOCH2–U–CH2–U–CH2–U–(CH2OH)–CH2–U (H+)…H2O |
157 | CH2OH–U–CH2OH (H+)‥.2H2O | 375 | Uron–CH2OH+CH2OH–U–(CH2OH)2+U–CH2OH\HOCH2–U–CH2–U–CH2–U–(CH2OH)–CH2–U (K+) |
171 | Uron–CH2OH (K+) U–CH2–U (K+) | 389 | HOCH2–U–CH2–U–CH2–U–(CH2OH)–CH2–U–CH2OH (Na+) |
187 | CH2OH–U–(CH2OH)2 (H+)…2H2O | 405 | HOCH2–U–CH2–U–CH2–U–(CH2OH)–CH2–U–CH2OH (K+) |
201 | Uron–(CH2OH)2\U–CH2–U–CH2OH (K+) | 419 | HOCH2–U–CH2–U–CH2–U–(CH2OH)–CH2–U–(CH2OH)2 (Na+) |
229 | HOCH2–U–(CH2OH)–CH2–U (H+)…2H2O | 447 | HOCH2–U–CH2–U–CH2–U–(CH2OH)–CH2–U–CH2–U (K+) |
243 | HOCH2–Uron–CH2–U\U–CH2–U–CH2–U (K+) | 477 | HOCH2–U–CH2–U–CH2–U–(CH2OH)–CH2–U–CH2–U–CH2OH (K+) |
273 | HOCH2–Uron–CH2–U–CH2OH\HOCH2–U–CH2–U–CH2–U (K+) | 491 | (HOCH2)2–U–CH2–U–CH2–U–(CH2OH)–CH2–U–CH2–U–CH2OH (Na+) |
303 | HOCH2–Uron–CH2U–(CH2OH)2\HOCH2–U–CH2–U–CH2–U–CH2OH (K+) | 521 | (HOCH2)2–U–CH2–U–CH2–U–(CH2OH)–CH2–U–CH2–U–(CH2OH)2 (Na+) |
317 | HOCH2–U–CH2–O–CH2–U–CH2OH\CH2OH–U–CH2–U–(CH2OH)2 (Na+)…2H2O | 549 | HOCH2–U–CH2–U–CH2–U–CH2–U–(CH2OH)–CH2–U–CH2–U–CH2OH (K+) |
333 | HOCH2–U–CH2–U–CH2–U–(CH2OH)2 (K+) | 579 | (HOCH2)2–U–CH2–U–CH2–U–CH2–U–(CH2OH)–CH2–U–CH2–U–CH2OH (K+) |
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Wang, H.; Cao, M.; Li, T.; Yang, L.; Duan, Z.; Zhou, X.; Du, G. Characterization of the Low Molar Ratio Urea–Formaldehyde Resin with 13C NMR and ESI–MS: Negative Effects of the Post-Added Urea on the Urea–Formaldehyde Polymers. Polymers 2018, 10, 602. https://doi.org/10.3390/polym10060602
Wang H, Cao M, Li T, Yang L, Duan Z, Zhou X, Du G. Characterization of the Low Molar Ratio Urea–Formaldehyde Resin with 13C NMR and ESI–MS: Negative Effects of the Post-Added Urea on the Urea–Formaldehyde Polymers. Polymers. 2018; 10(6):602. https://doi.org/10.3390/polym10060602
Chicago/Turabian StyleWang, Hui, Ming Cao, Taohong Li, Long Yang, Zhigang Duan, Xiaojian Zhou, and Guanben Du. 2018. "Characterization of the Low Molar Ratio Urea–Formaldehyde Resin with 13C NMR and ESI–MS: Negative Effects of the Post-Added Urea on the Urea–Formaldehyde Polymers" Polymers 10, no. 6: 602. https://doi.org/10.3390/polym10060602