Experimental methods in polymer degradation

UV/VIS lamps used in laboratories differ significantly, depending upon the manufacturers of lamps. The main differences are  

emission spectra (which are different for low, medium and high pressure lamps)  

The most common lamps used in the study of polymer photo(oxidative) degradation are [1762, 1769, 1770]  

If the mercury contains gas bubbles at one or both of the electrodes, it is impossible for the distribution to be such that both electrodes protrude just outside the surface of the mercury (Fig. 10.6e). To divide the mercury properly, in this case, first collect it all at the end of the discharge tube and then distribute it in the correct manner, using the method described above. 

On no account must a lamp be started if there is no mercury, or only very little, at one of the electrodes. These situations are illustrated in 

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Experimental methods in polymer degradation Table 10.8 Typical chromophores and their characteristics ... 

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