Characteristics of Ultraviolet Cured Glass–Epoxy Composites Part 2: Results and Discussion

Abstract

A curingsystem usingultraviolet radiation is proposed for use on a braidingmachine, which can expedite composite manufacturingand eliminate additional secondary processes. This work investigated some of the facts and characterized the processes to suit the design for the braiding machine. The addition of diacrylates and triacrylates was found to reduce the effects of oxygen quenching and increase the curingspeed of acrylated epoxy monomers. Mechanical testingwas performed to study these effects. Epoxies follow the cationic polymerization mechanisms. The preliminary study was carried out on epoxy (Shell Epon 826) with a cationic photoinitiator (Radcure, Uvacure 1590). It was found that on exposure to ultraviolet radiation, gelling takes place in 10 s. The degree of curing attained was found to be appreciable if cross-linkingagents like Imidazole or an anhydride was added to the formulation.

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