TIME CURE SUPERPOSITION DURING CROSS-LINKING
TIME CURE SUPERPOSITION DURING CROSS-LINKING
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DOI：
10.1021/ma00217a026
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发表时间：
1990-07-23
期刊：
影响因子：
5.5
通讯作者：
MARTIN, JE
中科院分区：
文献类型：
--
作者：
ADOLF, D;MARTIN, JE
利用动态标度理论研究了交联型聚合物在凝胶点附近的粘弹性，预测了不同反应程度下粘弹性函数的叠加情况。例如，为了叠加应力松弛模数，需要一个垂直位移来解释平衡模数随固化的增加G“~E8/3，以及水平位移来说明特征松弛时间的发散，~e~4，其中<；是反应的临界程度。对模型环氧化合物的实验表明，在凝胶点以下和之上都有很好的重叠，G“~e2-8±0.2和Rz~c~3‘9±0.2。这种叠加有效的临界区令人惊讶地宽，涵盖了反应的一半以上。
Using a dynamic scaling theory for the viscoelasticity of cross-linking polymers near the gel point, we predict the superposition of viscoelastic functions at differing extents of reactions. For example, to superpose the stress relaxation modulus, a vertical shift is needed to account for the increase in the equilibrium modulus with cure, G „~ e8/3, and a horizontal shift for the divergence of the characteristic relaxation time,~ e~ 4, where< is the critical extent of reaction. Experiments on model epoxies show excellent superpo-sition both below and above the gel point and give G „~ e2-8±0· 2 and rz~ c~ 3'9±0· 2. The critical regime where this superposition is valid is surprisingly wide, encompassing over half of the reaction.