Fabrication of novel wave-transparent HMPBO fibre/BADCy laminated composites

The method of "impregnation-winding-lamination-mould pressing" was performed to fabricate novel wave-transparent high modulus poly(p-phenylene-2,6-benzobisoxazole) fibre/bisphenol A cyanate ester resin (HMPBO fibre/BADCy) laminated composites. The "two-step approach" of methanesulfonic acid/γ-glycidoxy propyl trimethoxy silane (MSA/KH-560) was also proposed to functionalize the HMPBO fibres' surface. Results revealed that KH-560 was grafted on the HMPBO fibres' surface successfully. The functionalized HMPBO fibre/BADCy laminated composites possessed better ILSS & flexural strength, lower ε & tanδ, and higher heat-resistance index & T_g. The ILSS and flexural strength of the functionalized HMPBO/BADCy laminated composites were increased to 53.7 MPa and 753.7 MPa, respectively. The corresponding ε and tanδ were decreased to 2.93 and 0.00097, respectively. The corresponding heat-resistance index and T_g were increased to 219 °C and 236 °C, respectively. The functionalized HMPBO fibre/BADCy laminated composites display potential application in radomes and the antenna systems of aircrafts.