Cure curves, with phase transition

The curing of a diepoxide (AU) with DDM (Figure 11.13) carried out at different temperatures can be compared from the dynamic DSC curves (Figure 11.16) recorded for products cured in 120°C, 140°C and 160°C. The data demonstrate that stable materials with no phase transitions were formed (despite the small peak visible at about 50°C in all the cases), however the shapes of individual curves are somewhat different. Therefore it can be concluded that - as expected - different... 

The influence of styrene concentration in UPR on the miscibility with unsaturated polyester and the mechanical properties was investigated [24]. A commercial UPR containing 38 wt % styrene was used to prepare samples with 6-58 wt % styrene by partial evaporation of styrene in vacuo or dilution with fresh styrene. Sets of curves presenting the effect of styrene content on the glass transition temperature and the mechanical properties of the cured UPR vs. temperature were presented. Phase separation in the crosslinked UPR with increase in styrene concentration was observed. 

Nevertheless, the stuefy of DSC curves is also useful while defining the mechanism of cure reaction, its effect on degree of cross-linking and consequently on mechanical properties. DSC characterization is likewise applicable in defining the phase dynamics and transitions associated with the monolayers... 

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