Thermomechanical Analysis of Continuous Bamboo Strips Reinforced Vanillin‐Based Epoxy Resin Composites

ABSTRACT The majority of thermosetting epoxy resins employed in organic composites are petroleum‐based and impacted by REACh regulation. However, research is undertaken to make epoxy resins greener. The present study assesses the thermomechanical properties of a new vanillin‐based epoxy resin as well as epoxy bamboo strips composites (EBSC). The reinforcement/matrix mass ratio for the EBSC is near 35%. Thermogravimetric analysis (TGA) showed that the epoxy system and the composite do not present any weight loss below 200°C except for water desorption of, respectively, 2 and 5 wt%. Glass transition temperature ( T g ), determined by temperature modulated differential scanning calorimetry (TMDSC), is 64.5°C ± 3.0°C for the epoxy system and 74.3°C ± 0.9°C for the EBSC at the hydrated state. Moisture content of the samples is responsible for a 20°C drop in the T g for both materials. The study of the shear loss modulus obtained by dynamic mechanical analysis (DMA) reveals four molecular relaxations: β, ω, α 2 , and α 1 . At first, they are, respectively, attributed to localized movements of hydroxypropylether segments, network heterogeneities, and larger‐scale mobility in two networks with dissimilar crosslinking densities. Glassy shear moduli are 1.56 GPa for the epoxy resin and 1.43 GPa for the EBSC at room temperature.