Product specific thermal degradation kinetics of bisphenol F epoxy in inert and oxidative atmospheres using evolved gas analysis-mass spectrometry was written by Dwyer, Derek B.;Gallego, Nidia C.;Niedziela, Jennifer L.;Kapsimalis, Roger J.;Duckworth, Douglas C.. And the article was included in Journal of Analytical and Applied Pyrolysis in 2022.Reference of 620-92-8 The following contents are mentioned in the article:
Knowledge of the degradation kinetics for polymer materials is important for understanding thermal stability. Here, evolved gas anal.-mass spectrometry and pyrolysis gas-chromatog.-mass spectrometry were evaluated for the potential to deliver addnl. insight into thermal degradation kinetics of diglycidal ether of bisphenol F (DGEBF) epoxy thermoset under inert and oxidative atmospheres. Degradation products of selected precursor ions were evaluated for their uniqueness to the specific precursor using extracted ion thermographs. Unique mass peaks, solely attributed to a single reaction pathway of a specific product, were determined from extracted ion thermographs and used to determine both activation energy (Ea) and pre-exponential factors for the specific primary reaction pathways. These primary reaction pathways for DGEBF epoxy degradation were then evaluated in the context of transition state theory (TST) and related transition state enthalpies (ΔH‡) and entropies (ΔS‡) of activation to further elucidate the degradation process. It was determined under pyrolysis conditions, as suggested by the Ea, the formation of bisphenol F monomer was the rate-limiting step toward the formation of xanthene and phenol. In contrast, under thermo-oxidative conditions, reactions involving oxygen containing species were identified as the rate-limiting step for all observed products based on the large neg. ΔS‡ calculated from TST. This work demonstrates a powerful combination of technique and theory that can provide new insight into the degradation of polymer materials. This study involved multiple reactions and reactants, such as 4,4′-Methylenediphenol (cas: 620-92-8Reference of 620-92-8).
4,4′-Methylenediphenol (cas: 620-92-8) belongs to alcohols. Similar to water, an alcohol can be pictured as having an sp3 hybridized tetrahedral oxygen atom with nonbonding pairs of electrons occupying two of the four sp3 hybrid orbitals. Grignard and organolithium reagents are powerful tools for organic synthesis, and the most common products of their reactions are alcohols.Reference of 620-92-8
Referemce:
Alcohol – Wikipedia,
Alcohols – Chemistry LibreTexts