Olmos D, Aznar A J, Baselga J, González-Benito J
Department of Materials Science, Universidad Carlos III de Madrid, Avda. Universidad, 30, 28911 Leganés, Madrid, Spain.
J Colloid Interface Sci. 2003 Nov 1;267(1):117-26. doi: 10.1016/s0021-9797(03)00620-9.
The fluorescence response of the dansyl chromophore has been used to study the kinetic of epoxy curing processes. With this new method, comparison between the curing at the interface of a glass fiber/epoxy and in the epoxy bulk of a composite material was studied. The effect of two glass fiber surface treatments was investigated. Commercial E-glass fibers were surface coated with 3-aminopropyltriethoxysilane (APTES) and 3-aminopropylmethyldiethoxysilane (APDES). Fluorimetry (using fluorescent labels) and FT-NIR (Fourier transformed infrared spectroscopy in the near range) techniques were used to monitor the curing process in these composite materials. From the analysis of the data obtained, different simple kinetic models were discussed and apparent activation energies were obtained. Furthermore, from those techniques the respective results were compared to obtain complementary information. Independently of the sample and the technique used for the kinetic analysis, no variation of the activation energy of the epoxy curing reaction was found, which suggests that there are no changes in the mechanism of the reaction along the process. Fluorescence from dansyl located at the glass fiber/epoxy interface reflected that the kind of reinforcement treatment clearly affects the epoxy curing process exactly in that region. However, when analytical response comes from the whole system the mechanism of the reaction does not seem to change with the silane coating used although is quite different in comparison with the process at the interface.
丹磺酰发色团的荧光响应已被用于研究环氧固化过程的动力学。采用这种新方法，研究了玻璃纤维/环氧树脂界面处的固化与复合材料环氧树脂本体中的固化之间的比较。研究了两种玻璃纤维表面处理的效果。商用E玻璃纤维用3-氨丙基三乙氧基硅烷（APTES）和3-氨丙基甲基二乙氧基硅烷（APDES）进行表面涂层处理。荧光分析法（使用荧光标记）和傅里叶变换近红外光谱法（FT-NIR）被用于监测这些复合材料中的固化过程。通过对所得数据的分析，讨论了不同的简单动力学模型并获得了表观活化能。此外，通过这些技术将各自的结果进行比较以获得补充信息。无论用于动力学分析的样品和技术如何，均未发现环氧固化反应活化能的变化，这表明反应机理在整个过程中没有变化。位于玻璃纤维/环氧树脂界面处的丹磺酰的荧光反映出增强处理的类型在该区域确实明显影响环氧固化过程。然而，当分析响应来自整个体系时，尽管与界面处的过程相比有很大不同，但反应机理似乎不会因所用的硅烷涂层而改变。
