Controlled cationic curing of epoxy composites with photochemically modified silanol encapsulated carbon black

Epoxy resins have been an inspiration in adhesives and coatings, however, uneven photopolymerization kinetics result in wrinkled surface and filler segregation, causing aesthetic and mechanical damage. Hence a control over curing kinetics is required not only to dodge filler segregation but also to control composite surface smoothness. In this study, photochemical modification of carbon black with mercaptopropyltrimethoxysilane, has resulted in unique silanol dendrites exterior on carbon black. Kinetic investigation confirmed that E-a for cationic polymerization of modified CB composite is three folds less in comparison to neat matrix, and two folds less in comparison to unmodified CB composite. Silanol dendrites have contributed on epoxy curing kinetics, through activated monomer mechanism. Samples have been characterized through XPS, FTIR, SEM, TGA, DSC, Raman, and EDX.

Automated summary

In this study, photochemical modification of carbon black with mercaptopropyltrimethoxysilane has resulted in unique silanol dendrites on the surface. Kinetic investigation showed that the modified carbon black composite has a threefold lower activation energy for cationic polymerization, indicating faster curing kinetics.