Caponi S, Corezzi S, Fioretto D, Fontana A, Monaco G, Rossi F
Dipartimento di Fisica, Università di Trento, Via Sommarive 14, I-38050 Povo (Trento), Italy.
Phys Rev Lett. 2009 Jan 16;102(2):027402. doi: 10.1103/PhysRevLett.102.027402.
Raman-scattering measurements are used to follow the modification of the vibrational density of states in a reactive epoxy-amine mixture during isothermal polymerization. Combining them with Brillouin light and inelastic x-ray scattering measurements, we analyze the variations of the boson peak and of the Debye level while the system changes from liquid to glass upon increasing the number of covalent bonds among the constituent molecules. The shift and intensity variation of the boson peak are explained by the modification of the elastic properties throughout the reaction, and a master curve for the boson peak can therefore be obtained. Surprisingly, bond-induced modifications of the structure do not affect this master curve.
拉曼散射测量用于跟踪等温聚合过程中反应性环氧 - 胺混合物中态密度的振动变化。将这些测量与布里渊光和非弹性X射线散射测量相结合，我们分析了在组成分子间共价键数量增加时，系统从液体转变为玻璃态过程中玻色子峰和德拜能级的变化。玻色子峰的位移和强度变化通过整个反应过程中弹性性质的改变来解释，因此可以得到玻色子峰的主曲线。令人惊讶的是，键诱导的结构变化并不影响这条主曲线。
