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

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: see text] [Formula: see text] [Formula: see text] , 22 [Formula: see text] and 80 [Formula: see text] to determine the temperature-dependence of the thermoset’s mechanical properties in its service temperature range. The glass transition temperature [Formula: see text] was analyzed via dynamic mechanical analysis (DMA) and is approximately 119 [Formula: see text]. The tensile, compression and flexural strength at 22 [Formula: see text] are about 56 [Formula: see text] [Formula: see text] , 98 [Formula: see text] [Formula: see text] and 85 [Formula: see text] [Formula: see text] , respectively. The critical stress intensity factor [Formula: see text] and fracture energy [Formula: see text] at 22 [Formula: see text] are roughly [Formula: see text] [Formula: see text] [Formula: see text] m(0.5) and 510 [Formula: see text] 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.