Polymer degradation curves

FIGURE 8.12 (See color insert following page 530.) Rate of heat release curves of PC, PC/1 wt.% TPOSS, PC/2wt.% TPOSS, and PC/3 wt.% TPOSS. (From Song, L. et al., Polym. Degrad. Stab., 93, 627, 2008. With permission.)... 

In addition, we have probed hydrolyzed Estane sample with the NMR Mobile Universal Surface Explorer (NMR MOUSE) (10). This technique is a quick non-invasive technique to determine the effect that polymer degradation has on its physical properties. Polymer chain mobility can be detected by proton spin-spin relaxation time measurements of hydrolyzed Estane using the NMR MOUSE. The spin-spin relaxation time decay curve shows increased chain mobility upon hydrolysis (Figure 11). The decay curve is fitted with a biexponential decay function to give two T2 values. The T22 associated with the more mobile polymer chains shows an inverse relationship to the molecular weight decrease as would be expected. This technique shows promise as an in situ probe of hydrolysis in high explosives in a non-destructive manner. 

Some kinetic models for thermal or catalytic polymer degradation have been proposed. The commonly used approach is first-order kinetics to investigate the characteristics of degradation (Equation 9.1). In this approach at first the weight loss curve of polymers during the decomposition is determined, and overall rate constants are calculated... 

Figure 9.9. TG and DTG curves. Experimental (dotted line) and theoretical curves (full lines) for plasti-sols containing 65 phr of DBF (a), DOP (b) and DIDP (c), at 5°C/min. [Reprinted from Polymer Degradation and Stability, Vol 53, Beltran M., Marcilla A., PVC-plasticizer interactions during the thermal decomposition of PVC plastisols. Influence of the type of plasticizer and resin, p. 261-268, 1996, with permission from Elsevier Science],...

Figure 9.11. DTG curves for plastisols with resin E450 and 65 phr of DIBP, DOP, DIDP and DNA, at 5°C/min. [Reprinted from Polymer Degradation and Stability,...

Figure 1.11 An example of the chemiluminescence experiment showing the determination of the induction time. The curve corresponds to a sample of metallocene catalysed PP = 19,000, oxidised in at 140 °C. Reproduced with permission from J.M. Gomez-Elvira, P. Tiemblo, M. Elvira, L. Matisova-Rychla and J. Rychly, Polymer Degradation and Stability, 2004, 85, 873.

Figure 8.1 TGA and differential TGA curves of the ultraviolet cured TAEP and DAEEP films. Reproduced with permission from H. Liang and W. Shi, Polymer Degradation and Stability, 2004, 84, 525. 2004, Elsevier [1]...

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