Influence of the addition of erbium and ytterbium triflates in the curing kinetics of a DGEBA/o-tolybiguanide powder mixture
- 68 Downloads
Solid bisphenol-A epoxy resin (DGEBA) of medium molecular mass was cured using o-tolylbiguanide (TBG) as cross-linking agent. In order to improve the kinetics of the reactive system, two Lewis acid catalysts (erbium(III) and ytterbium(III) trifluoromethanesulfonates) were added in proportions of 1 phr. The kinetic study was performed by dynamic scanning calorimetry (DSC) and the complete kinetic triplet (E, A and g(α)) determined. The kinetic analysis was performed with an integral isoconversional procedure (model-free), and the kinetic model was determined by the Coats-Redfern method and through the compensation effect (IKR). All the systems followed the m=1.5/n=0.5 isothermal curing model simulated from non-isothermal experiments. The addition of a little proportion of ytterbium or erbium triflates accelerated the curing process. In order to extract further information about the role of the lanthanide triflates added to epoxy/TBG systems, the kinetic results were compared with our previous kinetic studies made on DGEBA/lanthanide triflates initiated systems.
Keywordscatalyst epoxy erbium triflate kinetics (polym.) ytterbium triflate
Unable to display preview. Download preview PDF.
- 2.U.S. Enviromental Protection Agency Center for Environmental Research Information, ’Technical Reference Manual on Techniques for reducing or eliminating releases of toxic chemicals in metal painting’, 1995.Google Scholar
- 3.R. S. Bauer and L. S. Corley, ’Epoxy Resins: Composites Technology’, S. M. Lee, Technomid Publishing Company, Inc., Pennsylvania 1989.Google Scholar
- 4.M. Ochi, K. Mimura and H. Motobe, J. Adhes. Sci. Technol., 8 (1994) 223.Google Scholar
- 6.J. M. Barton and K. Dusek, Adv. Polym. Sci., 72 (1985) 112.Google Scholar
- 7.T. Endo and F. Sanda, Macromol. Symp., 107 (1996) 237.Google Scholar
- 8.The Powder Coating Institute, ’PCI Technical Brief No. 1’, USA.Google Scholar
- 10.S. Kobayashi, Synlett, 689 (1996).Google Scholar
- 18.M. Meguro, N. Asao and Y. Yamamoto, J. Chem. Soc. Perkin Trans. I, 2597 (1994).Google Scholar
- 25.A. W. Coats and J. Redfern, Nature, 207 (1964) 290.Google Scholar
- 35.F. J. Gotor, J. M. Criado, J. Malek and N. Koga, J. Phys. Chem. A, 104 (2000) 10777.Google Scholar