Cure Behavior LCERs

The cure reaction of LCERs can have a large influence on the liquid crystalline phase as physical properties of the final cured material. Depending on the nature of the LC monomer and the type of reactive group, the liquid crystalline order may either decrease or increase as a result of the cure. Thus, examples exist in the literature of LCT s that undergo transitions from isotropic to nematic or smectic phases from nematic to smectics from nematic or smectic to isotropic and from smectic to nematic [30-37]. 

Even though DOMS/SAA experiences different amounts of cure in liquid crystalline phases at different cure temperature, the system seems to hold isoconversion theory of gelation. For example, at the cure temperature of 120°C, cure in the isotropic phase occurs up 

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The similar fracture behavior can be observed by comparing the fracture surfaces (Figure 11.20) of commercial DGEBA and a LCER 2,5-bis(4-diglycidyloxyphenyl)-l,3,4-oxadiazole (DGEOD) cured with DDM as observed for DOMS/DDM system. The fracture surface appears smooth and featureless under the SEM (Figure 11.18a), a typical characteristic of brittle fracture [55]. 

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