Preparation of Microcapsules Containing a Curing Agent for Epoxy Resin by Polyaddition Reaction with the Self-Assembly of Phase-Separated Polymer Method in an Aqueous Dispersed System

Abstract

To prepare cured epoxy resin particles encapsulating a curing agent (diamine), the self-assembly of phase-separated polymer (SaPSeP) method was developed to be applicable to polyaddition reaction of a stoichiometrically imbalanced system. The SaPSeP method was developed by the authors for preparation of micrometer-sized, hollow cross-linked polymer particles by radical polymerization based on the self-assembly of phase-separated polymer at the inner interface of particles. Although a polyaddition reaction, in general, requires that the reactants are in stoichiometric balance for the cure reaction to proceed well, diamine was successfully encapsulated within a cured epoxy resin shell by utilizing the SaPSeP method regardless of stoichiometric imbalance. The results provide further support of the previously proposed SaPSeP mechanism for the formation of hollow particles. Moreover, such diamine capsules can be employed in one-component epoxy adhesives.

Control of reactions and network structures of epoxy thermosets

“…Minami and coworkers use the so called Self-Assembly of Phase Separated Polymer method (SaPSeP) [166] in a dispersed aqueous medium to encapsulate an aliphatic diamine (3,9-dipropanamine-2,4,8,10-tetraoxaspiroundecane) in a cured epoxy shell [167]. They obtain capsules with a load percentage of 43 wt% in unreacted diamine.…”

“…Fig. 32 Schematic representation of the latent curing system proposed by Minami and coworkers [167]. Capsules loaded with diamine are dispersed in an epoxy resin.…”

Preparation and characterization of a novel microcapsule-type latent curing agent for epoxy resin

“…To solve this problem, imidazole must be converted to an unreactable latent curing agent at room temperature. Among all methods to prepare unreactable latent curing agent, the encapsulation is a feasible and economic one [26][27][28][29]. Recently, Lee et al [30] and Shin et al [21] have prepared the microcapsule of 2-methylimidazole curing agent using polycaprolactone as the shell material by the spray-drying method.…”

Microfluidic-Assisted Fabrication of Monodisperse Core–Shell Microcapsules for Pressure-Sensitive Adhesive with Enhanced Performance

“…Pressure-sensitive adhesives (PSA) based on microcapsules show the advantages of low price and easy operation, which have been applied in labels, adhesive tapes, the industrial processing of optoelectronic devices, etc. [9][10][11][12]. In PSA, partial components or the total formulation of adhesives can be encapsulated as the core materials, which are released by pressurized shell rupture to achieve on-demand bonding.…”