Reactive blending approach to modify spin‐coated epoxy film: Part II. Crosslinking kinetics

Abstract

Kinetics of the reactive blending of epoxy with a four-armed -caprolactone-based carboxylic acid end-functionalized oligomer was analyzed with a modelfree approach. The employment of a dual catalyst system ensured high density of crosslinking in the blends and minimized phase separation even when comparatively high concentration of the oligomer was incorporated. The two reactions were examined separately before analysis of the dual-catalyzed system. The apparent activation energy of the single-catalyzed reactions could be seen to fall into three regimes. It is proposed that regime I is due to reaction control, the middle part (II) to mass transport, and the high conversion tail (III) to structural control. The results of a thermal analysis carried out on the crosslinked samples corresponded well with the findings of the kinetic analysis. The combined kinetic and thermal results can be used in optimization of the crosslinking process.

The Interplay of Processing-Related Influences on the Formation of Volume Holographic Gratings in a Free-Surface Epoxy-Based Recording Material

“…As the reaction proceeds and the molecular weight of the epoxy network increases, the viscosity of the material starts to increase, resulting in gelation, vitrification and the formation of highly crosslinked solid epoxy [36]. The glass transition temperature of the evolving network increases and the activation energy decreases.…”

Reactive blending approach to modify spin‐coated epoxy film: Part I. Synthesis and characterization of star‐shaped poly(ϵ‐caprolactone)

“…In this article, we describe the synthesis of the oligomers, their reactive blending with SU8 epoxy, and selected surface and bulk properties of spin-coated films. In part II, 39 we will report the crosslinking kinetics of the dual-catalyzed crosslinking reaction.…”

Reactive compatibilization of poly(styrene‐ran‐acrylonitrile)/poly(ethylene) blends through the acid–epoxy reaction

“…30 SAN blends have been more focused on using the amine/maleic anhydride reaction, even though the synthesis of a relatively cheap amine-functional monomer is required. 30,[49][50][51][52][53] Therefore, using monomers that are commercially available is attractive and an acid functional terpolymer S/AN/AA was thus targeted here. Initially, conventional radical polymerization was used to determine the sensitivity of copolymer composition to initial monomer composition.…”

“…The acid/epoxy coupling has not been uniformly effective in some blend systems, particularly in highly incompatible blends with relatively thin interfaces . SAN blends have been more focused on using the amine/maleic anhydride reaction, even though the synthesis of a relatively cheap amine‐functional monomer is required . Therefore, using monomers that are commercially available is attractive and an acid functional terpolymer S/AN/AA was thus targeted here.…”