Improvement of the interfacial shear strength of poly(p‐phenylene benzobisoxazole) fiber/epoxy resin composite via a novel surface coating agent

Abstract

Poly(p-phenylene benzobisoxazole) (PBO) fiber with a smooth surface exhibits limited interfacial interaction with resin matrix. One of the effective strategies to improve the adhesion between the fiber and resin matrix is through surface modification of the fiber. In this study, we have proposed a novel surface treatment agent based on phosphoester cross-linked castor oil (PCCO) for effective surface treatment of PBO fibers. The surface treatment agent was prepared by a simple cross-linking reaction between hydroxy phosphorylated castor oil (PCO) and epoxy resin, with alcohol as the solvent at 65 C. Once the PBO fiber was treated with this agent, the interfacial adhesion between the PBO fiber and the epoxy resin could then be improved. Systematic analyses suggest that the surface treatment with (PCO 1 epoxy)/alcohol solution improves the interaction of the PBO fiber with the epoxy resin matrix. The PCCO coated onto the surface of PBO fiber acts as a coupling agent, improving the interfacial shear strength (IFSS) of the PBO fiber/epoxy resin composite. Results indicate a 156% increase in IFSS without compromising the mechanical properties of the fiber.

Compressive testing of thermoset composites reinforced with high-performance polymer fibres

“…The measured values are reasonably high compared to other microdroplet tests reported in the literature: 24 MPa for aramid/epoxy; 25 4.7 MPa, 26 5.5 MPa, 27 and 11.3 MPa 28 for untreated PBO/epoxy; and 19 MPa for untreated PAR/epoxy. 29 Higher values were found in single fibre pull-out tests: Mäder et al 30 measured 39–55 MPa for PBO/epoxy, and Zhandarov and Mäder 31 measured 42–50 MPa for two aramid/epoxy systems.…”

In situ growth of TiO2 nanoparticles onto PBO fibers via a mussel‐inspired strategy for enhancing interfacial properties and ultraviolet resistance

“…By contrast, as a facile and mild technique, surface coating with special function on the substrate materials has attracted the interest of many researchers. [1,2,[17][18][19] As PBO fibers are susceptible to damage from UV irradiation, different UV-resistant coatings have been prepared to protect the substrate material. Based on the UVabsorbing nature, titanium dioxide (TiO 2 ) nanoparticles have been introduced onto PBO fibers by sol-gel or sizing methods.…”

Branched Fluorine/Adamantane Interfacial Compatibilizer for PBO Fibers/Cyanate Ester Wave‐Transparent Laminated Composites

“…synthesized hydroxyphosphorylated castor oil (PCO) as an interfacial compatibilizer for PBO fibers/ PCO/epoxy composites. [ 29 ] In our previous work, Gu et al . synthesized fluorinated PBO precursor (epoxy‐ pre FPBO) to simultaneously improve the wave‐transparent performances and mechanical properties of modified bisphenol A type cyanate (FPBO‐ co ‐ BADCy) resins.…”