Preparation and characterization of high-performance pollen-enhanced epoxy resin composites

Epoxy resin, as a high-performance thermosetting material, is widely used in engineering. However, its insufficient toughness limits its application. Traditional fiber or nanoparticle reinforcement systems face high costs and poor environmental compatibility. Natural pollen, with its good mechanical properties and renewability, offers a new idea for the development of green reinforcement. In this study, pine pollen and sunflower pollen (0.1-0.5 wt%) were introduced to construct epoxy resin composites, and the effects of pollen type and content on the various properties of the materials were systematically investigated. The experimental results show that a good interfacial bonding was formed between the pollen and the resin, with an inevitable increase in the degree of crystallinity. Compared with pure epoxy resin, the pollen/epoxy resin composites exhibited significant optimization of mechanical properties: the elastic modulus reached up to 1.063 GPa (an increase of 55.3%), the tensile strength could be enhanced to 121 MPa (a rise of 83.3%), and the elongation at break could reach 5.59% (an increase of 11.6%). Meanwhile, the composites also demonstrated excellent UV resistance (T(UVA) could be reduced to 30%, a decrease of 57%, and T(UVB) could be reduced to 8%, a reduction of 73%) and antioxidant properties (49.6%, an increase of 38.9%). The research results are significant for the green toughening of epoxy resin matrices.