Abstract:
Proton CW and pulse NMR studies for furfuryl alcohol resin carbonized over the temperature range 60-860°C are performed. The results are interpreted in terms of structural and chemical changes taking place during heat treatment. Heating up to:
1.
(i) 240°C results in an increase in molecular weight and crosslinking;
2.
(ii) 320°C produces crosslinking sufficient to form a rigid structure;
3.
(iii) 380°C and higher leads to hydrogen release and appearance of paramagnetic centers.
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