| 초록 |
In this study, several types of flexible epoxy-based structural adhesives have been prepared to improve impact- and T-peel strengths. Flexible epoxies containing short or long thermoplastic backbones are synthesized and core shell rubber particles are dispersed in flexible epoxies. Additionally, nano-sized inorganic particles are added to flexible epoxy-based structural adhesives. Dicyandiamide as a curing agent and imidazole as a catalyst are used in the epoxy systems. Impact- and T-peel strength tests were performed at 23℃. Both CSR and flexible epoxy significantly improved impact-peel strengths at 23℃. And, nano-sized inorganic particles affected on T-peel strengths. Consequently, the coexistence of two components, CSR and flexible epoxy, in adhesive compositions played key roles in improving impact-peel strengths at 23℃. As long thermoplastic chains are incorporated into epoxy backbones to form flexible epoxy, phase separations are observed upon curing. |
