Journal of the Korean Wood Science and Technology

The Korean Society of Wood Science & Technology (한국목재공학회)
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Effects of Storage Time on Molecular Weights and Properties of Melamine-Urea-Formaldehyde Resins

  • JEONG, Bora (Department of Wood and Paper Science, Kyungpook National University) ;
  • PARK, Byung-Dae (Department of Wood and Paper Science, Kyungpook National University) ;
  • CAUSIN, Valerio (Departimento di Scienze Chimiche, Universita di Padova)
  • Received : 2019.09.23
  • Accepted : 2020.04.16
  • Published : 2020.05.25
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Abstract

As the properties of the melamine-urea-formaldehyde (MUF) resins were changing during their storage time, this study investigated the impacts of the synthesis method and melamine content of the MUF resins on the pH, apparent viscosity, molecular weights, and crystallinity to estimate these properties over storage times of up to 30 days. Melaminesat three addition levels (5, 10, and 20 wt% based on the resin solids) were simultaneously reacted with urea and formaldehyde (MUF-A resins), while those at the same addition levels were first reacted with formaldehyde and then with urea(MUF-B resins). The pH values of the MUF-A and MUF-B resins decreased linearly as the storage time increased; the apparent viscosity increased linearly for the low melamine contents (5% and 10%) but increased exponentially for 20%. As anticipated, the molecular weights (Mw and Mn) increased linearly with the storage time, with a steeper increase in the Mw of the MUF-B resins compared with that of the MUF-A resins. The crystallinity of the two resin types decreased with storage time at higher melamine content. The relationships between these properties and the storage time made it possible to estimate the property changes in these resins synthesized by the different synthesis methods and melamine contents; this could help predict the properties of such resins in the industry during their storage.

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References

  1. Despres, A., Pizzi, A. 2006. Colloidal aggregation of aminoplastic polycondensation resins: urea-formaldehyde versus melamine-formaldehyde and melamine- urea-formaldehyde Resins, Journal of Applied Polymer Science 100: 1406-1412. https://doi.org/10.1002/app.23230
  2. Dunky M. 1998 Urea-formaldehyde (UF) adhesive resins for wood. International Journal of Adhesives and Adhesion 18(2): 95-107. https://doi.org/10.1016/S0143-7496(97)00054-7
  3. Gavrilovic-Grmus, I., Dunky, M., Miljkovic, J., Djiporovic-Momcilovic, M. 2010a. Radial penetration of ureaformaldehyde adhesive resins into beech (Fagus Moesiaca) Journal of Adhesion Science and Technology 24(8-10): 1753-1768. https://doi.org/10.1163/016942410X507812
  4. Gavrilovic-Grmusa, I., Miljkovic, J., Ðiporovic-Momcilovic, M. 2010b. Influence of the degree of condensation on the radial penetration of ureaformaldehyde adhesives into silver fir (Abies alba, Mill.) wood tissue. Journal of Adhesion Science and Technology 24(8-10): 1437-1453. https://doi.org/10.1163/016942410X501034
  5. Hong, M.K., Park, B.D. 2017a. Effect of ureaformaldehyde resin adhesive viscosity on plywood adhesion. Journal of the Korean Wood Science and Technology 45(2): 223-231. https://doi.org/10.5658/WOOD.2017.45.2.223
  6. Hong M,K., Park, B.D., Kim, K.H., Shim, K. 2017b. Performance of Melamine-Urea-Formaldehyde Resin Adhesives at Various Melamine Contents for Bonding Glued Laminated Timber Under High Frequency Heating. Journal of the Korean Wood Science and Technology 45(4): 409-418. https://doi.org/10.5658/WOOD.2017.45.4.409
  7. Hse, C.Y., Fu, F., Pan, H. 2008. Melamine-modified urea formaldehyde resin for bonding particleboards. Forest Products Journal 58(4): 56-61.
  8. Hse, C.Y. 2009. Development of melamine modified urea formaldehyde resins based on strong acidic pH catalyzed urea formaldehyde polymer. Forest Products Journal 59(4): 19-25.
  9. Hindeleh, A.M., Johnson, D.J. 1971. The resolution of multipeak data in fibre science. Journal of Physics D: Applied Physics 4: 259-263. https://doi.org/10.1088/0022-3727/4/2/311
  10. Jahromi, S. 1999a. Storage stability of melamineformaldehyde resin solutions, 1. The mechanism of instability. Macromolecular Chemistry and Physics 200(10): 2230-2239. https://doi.org/10.1002/(SICI)1521-3935(19991001)200:10<2230::AID-MACP2230>3.0.CO;2-U
  11. Jahromi, S. 1999b. The storage stability of melamine formaldehyde resin solutions: III. Storage at elevated temperatures. Polymer 40(18): 5103-5109. https://doi.org/10.1016/S0032-3861(98)00724-1
  12. Jeong, B., Park, B.D. 2019. Effect of molecular weight of urea-formaldehyde resins on their cure kinetics, interphase, penetration into wood, and adhesion in bonding wood. Wood Science and Technology 53(3): 665-685. https://doi.org/10.1007/s00226-019-01092-1
  13. Jeong, B., Park, B.D. 2016. Measurement of molecular weights of melamine-urea-formaldehyde resins and their influences to properties of medium density fiberboards. Journal of the Korean Wood Science and Technology 44(6): 913-922. https://doi.org/10.5658/WOOD.2016.44.6.913
  14. Jeong, B., Park, B.D. 2017. Effect of analytical parameters of gel permeation chromatography on molecular weight measurements of urea-formaldehyde resins. Journal of the Korean Wood Science and Technology 45(4): 471-481. https://doi.org/10.5658/WOOD.2017.45.4.471
  15. Jeong, B., Park, B.D., Causin, V. 2019. Influence of synthesis method and melamine content of ureamelamine- formaldehyde resins to their features in cohesion, interphase, and adhesion performance. Journal of Industrial Engineering and Chemistry 79: 87-96. https://doi.org/10.1016/j.jiec.2019.05.017
  16. Jeremejeff, J. 2012. Investigation of UF-resins- The Effect of The Formaldehyde/Urea Mole Ratio During Synthesis, Master of Science Thesis, KTH Royal Institute of Technology, Stockholm, Sweden,
  17. Johnson, S.E., Kamke, F.A. 1992. Quantitative analysis of gross adhesive penetration in wood using fluorescence microscopy. Journal of Adhesion 40: 47-61. https://doi.org/10.1080/00218469208030470
  18. Kim, S., Kim, H.J., Kim, H.S., Lee, Y.K., Yang, H.S. 2006. Thermal analysis study of viscoelastic properties and activation energy of melaminemodified urea formaldehyde resins. Journal of Adhesion Science and Technology 20(8): 803-816. https://doi.org/10.1163/156856106777638671
  19. Lei, H., Pizzi, A., Du, G., Despres, A. 2006. Variation of MUF and PMUF resins mass fractions during preparation. Journal of Applied Polymer Science 100(6): 4842-4855. https://doi.org/10.1002/app.22608
  20. Lubis, M.A.R., Park, B.D., Lee, S.M. 2019a. Performance of Hybrid Adhesives of Blocked- pMDI/Melamine- Urea-Formaldehyde Resins for the Surface Lamination on Plywood. Journal of the Korean Wood Science and Technology 47(2): 579-586.
  21. Lubis, M.A.R., Jeong, B., Park, B.D., Lee, S.M., Kang, E.C. 2019b. Effect of Synthesis Method and Melamine Content of Melamine-Urea-Formaldehyde Resins on Bond-Line Features in Plywood. Journal of the Korean Wood Science and Technology 47(5): 579-586. https://doi.org/10.5658/wood.2019.47.5.579
  22. Malkin, A.Y., Kulichikhin, S.G. 1991. Rheokinetics of curing. In: Polymer Compositions Stabilizers/Curing. Springer, Berlin, Germany pp. 217-257.
  23. Mattheij, J., Evers, L., Litvinov, V. 2005. The Phenomena of Instability of MUF Resins: Improve your Amino Resin Performance: 9th European Panel Products Symposium. October 5-7. pp. 187-199.
  24. Mijatovic, J., Binder, W.H., Kubel, F., Kantner, W. 2002. Studies on the stability of MF resin solutions: investigations on network formation. In: Macromolecular Symposia, WILEY-VCH Verlag GmbH, Weinheim, Germany 181(1): 373-382.
  25. No, B.Y., Kim, M.G. 2004. Syntheses and properties of low-level melamine-modified urea-melamine- formaldehyde resins. Journal of Applied Polymer Science 93(6): 2559-2569. https://doi.org/10.1002/app.20778
  26. Nuryawan, A., Park, B.D., Singh, A.P. 2014. Penetration of urea-formaldehyde resins with different formaldehyde/ urea mole ratios into softwood tissues. Wood Science and Technology 48(5): 889-902. https://doi.org/10.1007/s00226-014-0649-9
  27. Paiva, N.T., Pereira, J., Ferra, J.M., Cruz, P., Carvalho, L., Magalhães, F.D. 2012. Study of influence of synthesis conditions on properties of melamineurea formaldehyde resins. International Wood Products Journal 3(1): 51-57. https://doi.org/10.1179/2042645312Y.0000000009
  28. Paiva, N.T., Pereira, J., Ferra, J.M., Cruz, P., Carvalho, L., Magalha, F.D. 2013. Study of influence of synthesis conditions on properties of melamineurea formaldehyde resins. International Wood Products Journal 3: 51-57. https://doi.org/10.1179/2042645312Y.0000000009
  29. Pendlebury, E., Lei, H., Antoine, M.L., Pizzi, A. 2010. Melamine-Formaldehyde Resins without Urea for Wood Panels. Journal of Adhesion Science and Technology 24(8-10): 1415-1422 https://doi.org/10.1163/016942410X501016
  30. Pizzi, A., Mittal, K. 1994. Handbook of Adhesive Technology. Marcel Dekker, New York, USA.
  31. Siimer, K., Kaljuvee, T., Christjansonoch, P., Pehk, T. 2005. Changes in Curing Behavior of Aminoresins During Storage. Journal of Thermal Analysis and Calorimetry 80: 123-130. https://doi.org/10.1007/s10973-005-0623-8
  32. Zanetti, M., Pizzi, A. 2003. Colloidal aggregation of MUF polycondensation resins: formulation influence and storage stability. Journal of Applied Polymer Science 91(4): 2690-2699. https://doi.org/10.1002/app.13452