High-performance carbon fiber-reinforced epoxy resin composites based on novel, environmentally friendly, stability, and heat-moisture resistant nano emulsion encapsulated POSS sizing agent interface modification

Abstract

Considering the development of CFRPs, addressing the challenge through the simplistic industrial operational methods to achieve high strength and toughness in carbon fiber-reinforced epoxy resin (EP) composites (CFRPs) is imperative. In this work, an innovative approach introduced to improve the strength and toughness of CFRPs by application of a nano emulsion encapsulated polyhedral oligomeric silsesquioxane (POSS) sizing agent (POE sizing agent). The employment of a POE sizing agent markedly enhanced the surface energy and roughness of carbon fibers (CF) as well as the interface properties of CFRPs. Furthermore, the 10-PCF (10 wt% POE sizing CF) reinforced EP unidirectional CFRPs demonstrated superior strength and toughness. Relative to the DCF (Desizing CF) reinforced EP unidirectional CFRPs, their interlaminar shear strength, flexural strength, and unnotched impact strength increased by 24.9 %, 37.8 %, and 45.6 %, respectively, reaching 99.8 ± 2.3 MPa, 1376.8 ± 21.6 MPa, and 94.9 ± 4.6 kJ/m2. Concurrently, the 10-PCF reinforced EP composite laminates exhibited outstanding impact resistance, minimal damage area, and enhanced compressive strength after impact. Additionally, the strength, bundling, and flexibility of the sized CF were maintained, ensuring the processability of CF. The utilization of POE sizing agent for strength and toughness improvement in CFRPs offers a straightforward and industrially feasible approach. This research opens up a novel strategy for high-performance CF and CFRPs preparation.