Revealing nanoscale dynamics during an epoxy curing reaction with x-ray photon correlation spectroscopy
Revealing nanoscale dynamics during an epoxy curing reaction with x-ray photon correlation spectroscopy
复制标题
利用 X 射线光子相关光谱揭示环氧树脂固化反应过程中的纳米级动力学
DOI：
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发表时间：
2020
期刊：
影响因子：
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通讯作者：
T. Koga
中科院分区：
文献类型：
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作者：
B. Yavitt;Daniel Salatto;Zhixing Huang;Yuto T. Koga;M. Endoh;L. Wiegart;Sascha Poeller;S. Petrash;T. Koga
研究了工业环氧胶粘剂在热触发固化过程中纳米级性能的演变。我们使用x射线光子相关光谱（XPCS）通过反映热固性网络形成的填充粒子的局部动力学来跟踪固化反应的进展。通过对XPCS得到的强度-强度自相关函数的辨识和分析，解决了非平衡动力学问题。计算了填料的特征时间尺度和局部速度作为时间和温度的函数。我们发现，在接近固化温度（Tcure）时，动力学加速，一旦达到Tcure，动力学迅速衰减。我们将XPCS的结果与传统的差示扫描量热法（DSC）进行了比较。通过XPCS对固化反应的纳米级表征的演示和实现，为环氧热固性材料和其他工业粘合剂体系的未来开发和优化提供了有益的帮助。
The evolution of nanoscale properties is measured during the thermally triggered curing of an industrial epoxy adhesive. We use x-ray photon correlation spectroscopy (XPCS) to track the progression of the curing reaction through the local dynamics of filler particles that reflect the formation of a thermoset network. Out-of-equilibrium dynamics are resolved through identification and analysis of the intensity–intensity autocorrelation functions obtained from XPCS. The characteristic time scale and local velocity of the filler is calculated as functions of time and temperature. We find that the dynamics speed up when approaching the curing temperature (Tcure), and decay rapidly once Tcure is reached. We compare the results from XPCS to conventional macroscale characterization by differential scanning calorimetry (DSC). The demonstration and implementation of nanoscale characterization of curing reactions by XPCS proves useful for future development and optimization of epoxy thermoset materials and other industrial adhesive systems.