Curie point filament pyrolyser technique

Method 10.1 - Pyrolysis-Gas chromatography of Polymers. Curie Point Filament Pyrolyser Technique [16]... 

This Curie point filament pyrolyser technique enables unknown polymers to be identified. 

In this Curie point filament pyrolysis technique the polymer is pyrolysed at a controlled temperature and the pyrolysis products passed into a gas chromatograph. Relative retention data and peak height ratio data obtained when compared with data obtained from known polymers provide a means of identifying the unknown polymer. 

The derivatization is commonly done for medium and low volatility compounds. The volatile compounds are more frequently analyzed by on-line techniques without derivatization, although on-line derivatization is occasionally utilized (such procedures were discussed in Section 2.7). When the off-line derivatization is done for the pyrolysate generated in a furnace, no particular precautions are recommended. For Curie-point or filament type pyrolysers, the pyrolysate can be collected in a deactivated piece of capillary column connected to the pyrolyser and cooled either in an ice bath or at lower temperatures needed for capturing more volatile compounds. 

Juvet and co-workers [4] have used this technique for the preparation of fingerprint pyrograms of polymers. They claim that this technique yields considerably more simple and reproducible decomposition patterns than filament, furnace, and Curie point pyrolysers and claim that this is due to greater control of energy input and a more predictable manner in which the polymers decompose photolytically. Photolysis is carried out using a pure thin film of the polymer which is then irradiated using a medium-pressure mercury source. The photolysis products are swept onto a GC to produce a pattern characteristic of the polymer. The retention indexes of the photolysis products of some common polymers are given in Table 6.2. 

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