Effects of degradation

Outdoor studies by Union Carbide [11], shown in Fig. 8.5 illustrated the effects of both location and season on the rates of embrittlement of a 3 per cent CO polymer. Specimens cut from 18 mm thick extruded sheet, placed at a 45° angle to the south, lost elongation very rapidly in Florida, USA, in February, taking about two weeks to embrittle. New Jersey exposures in January-February resulted in embrittlement failures after about 4 weeks. Summer exposures at those locations were about twice as fast in reaching complete loss of elongation in both cases. Statz and Dorris [2] showed that a 1% CO film failed (reached zero elongation) in 4-5 days in Fresno, CA, USA, in June and survived about 60 days in Fairbanks, Alaska in September-November. 

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Shephard, N.E., Klosowski, J.M. and Wolf, A.T., Effects of degradation factors on sealant adhesion, in press. 

Sinko et al. [32] extended the macroscopic mass balance approach to include chemical and enzymatic degradation, where only highly soluble drugs were taken into account. When the effect of degradation is considered, the total loss in the intestinal tube becomes... 

Experiments done in the absence of an external stress showed that the effects of degradation crosslinking are significant at relatively short times of UV exposure, and confirmed that the photodegradation is essentially in the surface layers. The oxidized layer thickness appeared to remain more or less constant after a certain exposure. 

These techniques, all of which involve transitions between electronic energy levels, have to greater or lesser extents, as appropriate, found uses in monitoring the effects of degradation and oxidation on polymers. 

The effect of degradation agents on low temperature behaviour must be relevant in many applications but is virtually never specifically measured. There are low temperature tests for flexible materials (ISO 458 [36] and ISO 974 [37]), but generally DMTA or impact methods might be more appropriate. 

Quality can be regarded as a measure of the suitability of a fruit juice, fruit juice concentrate or fruit juice extract for an intended application. In general, whatever the application, it will be the consistency in performance of the product, from batch to batch and season to season, that is the prime concern. In order to meet quality targets, therefore, it becomes critical that processing is carried out in the correct manner using fruit of an optimum level of maturity, and that the product is stored under suitable conditions to limit effects of degradation during a required shelf-life. 

Effects of Degradation. The accumulation of degradation products in the solvent can lead to different types of damage that disrupt the PUREX process ... 

Effects of Degradation The effects of radiolytic degradation are highly dependent on the experimental conditions ... 

B. The extractable pH of many well-washed photographic prints has been in ihe range of 5.5 to 6.0 (only a medium permanence level by ASTM Specification D-3290-74), but well-washed photographic prints have endured for many years. Estimates of paper permanence based upon rates of change at several elevated temperatures assess the overall effect of degradative reactions and resistance to those reactions, including the effects of acidity. 

The biodegradation of Ecoflex film was tested under composting conditions. After 100 days in a composting environment more than 90% of the carbon in the polymer was converted to carbon dioxide. Tests also showed no toxic effects of degradation intermediates. 

To cure the effects of degradation, various polymeric consolidation materials were applied to artificially degraded cloth. Because long-term stability and ultimate consequences of treatment were not determined, recommendations for this use were not given (10). 

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