l-Arginine as Bio-Based Curing Agent for Epoxy Resins: Temperature-Dependence of Mechanical Properties

Abstract

The precise characterization of new bio-based thermosets is imperative for the correct assessment of their potential as matrix material in fiber-reinforced polymer composites. Therefore, the mechanical properties of diglycidyl ether of bisphenol a (DGEBA) cured with l-arginine were investigated to determine whether the bio-based thermoset possesses the required mechanical properties for application as a matrix material. The cured thermoset is called Argopox. The mixture of amino acid and epoxy resin was prepared via three-roll milling and cured in the presence of an urea-based accelerator. The tensile, compression, flexural and toughness properties of Argopox were characterized at (Formula presented.) (Formula presented.) (Formula presented.), 22 (Formula presented.) and 80 (Formula presented.) to determine the temperature-dependence of the thermoset’s mechanical properties in its service temperature range. The glass transition temperature (Formula presented.) was analyzed via dynamic mechanical analysis (DMA) and is approximately 119 (Formula presented.). The tensile, compression and flexural strength at 22 (Formula presented.) are about 56 (Formula presented.) (Formula presented.), 98 (Formula presented.) (Formula presented.) and 85 (Formula presented.) (Formula presented.), respectively. The critical stress intensity factor (Formula presented.) and fracture energy (Formula presented.) at 22 (Formula presented.) are roughly (Formula presented.) (Formula presented.) (Formula presented.) m0.5 and 510 (Formula presented.) m−, respectively. Consequently, Argopox possesses mechanical properties that reach performance levels similar to that of materials which are already used as matrix for fiber reinforced composites.