Polymer lifetime prediction

Reassessing Polymer Lifetime Prediction Methods with Improved Characterization and Diagnostics... 

Projection of material behavior Polymer lifetime prediction Elastomer low-temperature properties... 

Polymer lifetime prediction Projection of material behaviour Resin cure Shrinkage State transitions... 

L. Matisova-Rychla and J. Rychly, Inherent relations of chemiluminescence and thermooxidation of polymers, In R.L. Clough, N.C. Billingham and K.T. Gillen (Eds.), Advances in Chemistry, Series 249 Polymer Durability, Degradation, Stabilization and Lifetime Prediction. American Chemical Society, Washington, DC, 1996, p. 175. 

The high level of safety and reliability required of nuclear power stations has meant that systematic estimates of polymer lifetime have been performed more widely here than in any other industry. The approach is described in Section 5.3. Many applications of polymers are in locations that cannot be monitored by regular inspection. The practice has been to subject polymers in these regions to independent assessment or environmental qualification , a process in which their potential degradation mechanisms are identified within a worst case environment of 40 °C and high humidity. If the predicted lifetime of a component is less than the design life of 40 years a schedule is laid down for its replacement. 

In practice, most lifetime prediction is based on service experience. Depending on the industry concerned, this can take the form of planned examination of components at the end of their service life or be limited to the explanation of warranty returns. Experience with polymers is now sufficiently long for service experience to be a prime source of information for components with lifetimes of up to 35 years. The construction industry provides a good example of systematic listing of component lifetimes, related to minimum quality levels and modified according to the service conditions. The electrical industry applies statistical methods to life components and predict failures. This, however, strays into the general field of engineering component lifetimes. In this book we are concerned with materials rather than components. 

Johnston RT, Morrison EJ (1996) In Clough RL, Billingham NC, Gillens KT (eds) Polymer durability degradation, stabilisation and lifetime prediction, Advances in Chem Series-249. American Chemical Society, Washington, p 651... 

J. Verdu, X. Colin, B. Fayolle, and L. Audouin, Methodology of lifetime prediction in polymer aging. J. Testing Eval., 35(3), 289-296 (2007). 

S. Halim Hamid and I. Hussain, Lifetime prediction of plastics. In Handbook of Polymer Degradation, 2nd edn., S.S. Halim Hamid (ed.), Dekker, New York, pp. 699-726, (2000). 

Schwetlick K and Habicher W D (1996) Action mechanism of phosphite and phosphonite stabilizers, In Polymer durability degradation, stabilization and lifetime prediction, Clough R L, Billingham N C and Gillen K T (Eds), Adv Chem Ser 249 349-358. 

Fatigue resistance of polymers in a stress cracking environment is a complex topic where molecular variables have a strong influence. FCP experiments are a fast and effective method for determining the resistance to FCP in stress cracking environments and hence to predict polymer lifetime. Other mechanical testing methods have also been cited as they are somewhat more common. 

A Nonempirical Model for the Lifetime Prediction of Polymers Exposed in Oxidative Environments... 

This paper presents a non-empirical kinetic model for the lifetime prediction of polymers exposed in their normal use conditions. After having described the different components (the core, the optional layers) of the model, its efficiency is demonstrated for polyethylene in large temperature and y dose rate ranges. Future developments are briefly presented. 

Since the end of the 90 s, our group has been developing a non-empirical kinetic model, named KINOXAM, for the lifetime prediction of polymers and polymer matrix composites in their use conditions. The model is totally open. It is composed of a core, common to all types of polymers, derived from the now well-known closed-loop mechanistic scheme (/). Around this core, various optional layers can be added according to the complexity of oxidation mechanisms and the relationships between the structural changes taking place at the molecular scale and the resulting ones at larger scales (the macromolecular and macroscopic scales). 

A non-empirical kinetic model was developed for the lifetime prediction of polymer parts in their normal use conditions. This model gives access to the spatial distribution (in the sample thickness) of the structural changes at the different scales and the resulting changes of normal use properties. Its efficiency was demonstrated for many substrates in large temperature and dose rate ranges. Here, we have paid special attention to PE radio-thermal oxidation. 

B. Ivan, Degradation, Stabilization and Lifetime prediction. In Polymer Durability, R. Clough, R. C. Billingham, K. T. Gillen (eds) Advances in Chemistry, American Chemical Society Washington, D.C., 1995 19-32. 

Fatigue lifetime predictions in polymers therefore cannot be simply determined by a straightforward linear cumulative damage approach. This is especially true when crack growth mode transitions are observed and when strong history dependence of crack growth behavior occurs. 

Application of New Kinetic Techniques to the Lifetime Prediction of Polymers from Wei t-Loss Data... 

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