Curing of epoxy resin induced by femtosecond laser pulse

Abstract

The possibility of curing of epoxy resin induced by femtosecond laser beam was explored through choosing different initiators. Absorption spectroscopy, infrared spectroscopy (IR), stereomicroscopy and scanning electron microscopy (SEM) were applied to analyze the structure of epoxy resin systems after irradiation with a femtosecond laser beam. The experimental results show that the epoxy resin systems containing diaryliodonium salts can be cured by irradiation of femtosecond laser pulse, while the systems containing benzoin can not be cured. It is found that diaryliodonium salts decompose under the irradiation of femtosecond laser pulse through multi (two)-photon absorption, initiating the ring-opening polymerization of epoxy resin. And the appearance of cured area has a sheet structure consisting of many tiny lamellar structures.

Keywords

epoxy resin / femtosecond laser / photopolymerization / curing / microstructure

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