Silicone-modified phenolic resin: Relationships between molecular structure and curing behavior

A silicone-modified phenolic resin (SPF) is synthesized by in-situ polymerization of 4,4′-(1,5-dipropyl-3,3-diphenyl-1,1,5,5-tetramethyltrisiloxane)bis-2-methoxyphenol(TDS), phenol and formaldehyde. The curing reaction and kinetics of SPF with hexamethylenetetramine (HMTA) are studied using a differential scanning calorimeter (DSC) in terms of the model-fitting and isoconversional methods. The results are described by Å esták-Berggren model precisely. The reaction kinetics show that the nonisothermal curing reaction of SPF/HMTA is autocatalytic, and is more affected by diffusion controlled process than PF/HMTA at high conversion stage. The isothermal conversion is predicted by using the model-free Vyazovkin method, exhibiting good agreement with experimental data. This study provide a method to understand how the silicone modifier affect the affect the curing behaviors of phenolic resins.