A modelling approach for the heterogeneous oxidation of elastomers
A modelling approach for the heterogeneous oxidation of elastomers
复制标题
弹性体非均相氧化的建模方法
DOI：
10.1007/s00161-017-0568-8
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发表时间：
2017
影响因子：
2.6
通讯作者：
A. Lion
中科院分区：
文献类型：
--
作者：
Herzig;L. Sekerakova;M. Johlitz ;A. Lion
氧对弹性体的影响，称为氧化，是最重要的老化过程之一，在当今的应用中变得越来越重要。与热效应以及抗氧化剂的相互作用使聚合物的氧化成为一个复杂的过程。根据所选择的聚合物和环境条件，老化过程可能完全不同。在许多情况下，氧的影响仅限于样品的表面层，通常称为扩散限制氧化。对于弹性体组件的寿命预测，必须详细了解热氧化老化过程中氧分子的吸收和扩散行为以及它们如何与弹性体反应。对工业上使用的弹性体材料进行实验研究，以开发和拟合模型，该模型应能够预测氧的渗透和消耗以及机械性能的变化。后者对于橡胶部件的技术应用至关重要。氧化在整个弹性体组分上不均匀地发生。因此，包括老化效应的材料模型必须被放大，以考虑非均匀老化，这在很大程度上取决于老化温度。必须严格分析高温对加速老化的影响，并考虑对渗透和扩散系数的影响。这项工作提出了现象学模型，描述了氧的吸收和扩散到弹性体的基础上，正在进行的化学过程和扩散限制修改的改进的理解。一方面，氧吸收是仿照亨利定律，其中溶解度是一个函数的温度以及老化进程。后者是一个不可逆的过程，由一个内微分演化方程描述。另一方面，氧向材料中的进一步扩散由基于Fick定律的模型描述，该模型由反应项修改。演化的扩散反应方程取决于老化温度以及老化的进展，并且能够描述扩散限制氧化。
The influence of oxygen on elastomers, known as oxidation, is one of the most important ageing processes and becomes more and more important for nowadays applications. The interaction with thermal effects as well as antioxidants makes oxidation of polymers a complex process. Based on the polymer chosen and environmental conditions, the ageing processes may behave completely different. In a lot of cases the influence of oxygen is limited to the surface layer of the samples, commonly referred to as diffusion-limited oxidation. For the lifetime prediction of elastomer components, it is essential to have detailed knowledge about the absorption and diffusion behaviour of oxygen molecules during thermo-oxidative ageing and how they react with the elastomer. Experimental investigations on industrially used elastomeric materials are executed in order to develop and fit models, which shall be capable of predicting the permeation and consumption of oxygen as well as changes in the mechanical properties. The latter are of prime importance for technical applications of rubber components. Oxidation does not occur homogeneously over the entire elastomeric component. Hence, material models which include ageing effects have to be amplified in order to consider heterogeneous ageing, which highly depends on the ageing temperature. The influence of elevated temperatures upon accelerated ageing has to be critically analysed, and influences on the permeation and diffusion coefficient have to be taken into account. This work presents phenomenological models which describe the oxygen uptake and the diffusion into elastomers based on an improved understanding of ongoing chemical processes and diffusion limiting modifications. On the one side, oxygen uptake is modelled by means of Henry’s law in which solubility is a function of the temperature as well as the ageing progress. The latter is an irreversible process and described by an inner differential evolution equation. On the other side, further diffusion of oxygen into the material is described by a model based on Fick’s law, which is modified by a reaction term. The evolved diffusion-reaction equation depends on the ageing temperature as well as on the progress of ageing and is able to describe diffusion-limited oxidation.
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影响因子：
5.9
作者：
M. Celina;G. George;D. Lacey;N. Billingham
通讯作者：
N. Billingham
12 – 弹性体和橡胶
影响因子：
5.9
作者：
L. McKeen
通讯作者：
L. McKeen
使用呼吸计测量环境温度下聚合物材料的氧化速率。
影响因子：
4.6
作者：
R. Assink;M. Celina;J. M. Skutnik;D. J. Harris
通讯作者：
D. J. Harris
DOI：
10.1080/00218464.2012.682905
发表时间：
2012
期刊：
The Journal of Adhesion
影响因子：
--
作者：
M. Johlitz
通讯作者：
M. Johlitz
硫硫化天然橡胶弹性体网络：通过组合技术关联交联密度、链取向和机械响应
影响因子：
5.5
作者：
A. Vieyeres;R. Pérez-Aparicio;P.-A. Albouy;O. Sanseau;K. Saalwächter;D. R. Long;P. Sotta
通讯作者：
P. Sotta