Cationic polymerization of diglycidyl ether of bisphenol A resins initiated by benzylsulfonium salts
Polymers and High Performance Materials
Benzylsulfonium salts are latent thermal cationic initiators that dissociate on heating to form benzyl cations chat can initiate polymerization. This paper describes the cure behavior of commercial epoxy resins using 1-(p-methoxybenzyl)tetrahydrothiophenium hexafluoroantimonate . The thermal cationic cure of bisphenol A diglycidylether (DGEBA) resins was investigated using differential scanning calorimetry (DSC). DsC revealed complex cure behavior as indicated by multiple exotherms. The resins cured rapidly at low initiator concentrations with gelation occurring in 3.5 and 1.5 min at 75 and 85 degrees C, respectively, at conversions of epoxy groups alpha = 0.2-0.3. Cure kinetic were evaluated from both dynamic and isothermal DSC measurements. The effects of initiator concentration, isothermal cure temperature and heating rate on the cure behavior and mechanisms, especially involving potential termination pathways, are discussed.
Mathias, L. J.
(1997). Cationic polymerization of diglycidyl ether of bisphenol A resins initiated by benzylsulfonium salts. POLYMER COMPOSITES, 18(3), 348-367.
Available at: http://aquila.usm.edu/fac_pubs/5329