TIME TEMPERATURE TRANSFORMATION (TTT) CURE DIAGRAM - MODELING THE CURE BEHAVIOR OF THERMOSETS
TIME TEMPERATURE TRANSFORMATION (TTT) CURE DIAGRAM - MODELING THE CURE BEHAVIOR OF THERMOSETS
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DOI：
10.1002/app.1983.070280810
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发表时间：
1983-01-01
影响因子：
3
通讯作者：
GILLHAM, JK
中科院分区：
文献类型：
--
作者：
ENNS, JB;GILLHAM, JK
通过动态力学光谱（扭辫分析和流变动态光谱仪）、红外光谱和凝胶分数实验，在宏观和分子水平上测量了胺固化环氧树脂（Epon 828/PACM-20）等温固化的凝胶化和玻璃化时间。凝胶化和玻璃化的转化程度和等温固化温度之间的关系形成的时间-温度-转化（TTT）固化图，其中的时间凝胶化和玻璃化在等温固化与温度的理论模型的基础上进行预测。该模型表明，玻璃化曲线的“S”形取决于反应动力学，以及系统的物理参数，即，未固化树脂的玻璃化转变温度（Tg 0）、完全固化树脂的玻璃化转变温度（Tg∞）和凝胶的玻璃化转变温度（gelTg）。还描述了反应体系在凝胶化和/或玻璃化之前的体积粘度。
The times to gelation and to vitrification for the isothermal cure of an amine‐cured epoxy (Epon 828/PACM‐20) have been measured on macroscopic and molecular levels by dynamic mechanical spectrometry (torsional braid analysis and Rheometrics dynamic spectrometer), infrared spectroscopy, and gel fraction experiments. The relationships between the extents of conversion at gelation and at vitrification and the isothermal cure temperature form the basis of a theoretical model of the time–temperature–transformation (TTT) cure diagram, in which the times to gelation and to vitrification during isothermal cure versus temperature are predicted. The model demonstrates that the “S” shape of the vitrification curve depends on the reaction kinetics, as well as on the physical parameters of the system, i.e., the glass transition temperatures of the uncured resin (Tg0), the fully cured resin (Tg∞), and the gel (gelTg). The bulk viscosity of a reactive system prior to gelation and/or vitrification is also described.