Poly(p-phenylene-2,6-benzobisoxazole) (PBO) fibers display weak outdoor stability and reliability due to their poor UV resistance and chemically inert surface. In this work, calcia-doped ceria (Ce_0.8Ca_0.2O_1.8) nanoparticles was fabricated via chemical co-precipitation method, and the novel Ce_0.8Ca_0.2O_1.8/P(S-co-BCB-co-MMA) organic-inorganic hybrid coating was then designed and prepared for surface functionalization of PBO fibers (PBO@P-Ce_0.8Ca_0.2O_1.8). Organic-inorganic hybrid coating presents high surface roughness and excellent UV resistance. When the concentration of Ce_0.8Ca_0.2O_1.8 nanoparticles with the particle size of about 50 nm is 0.6 wt%, PBO@P-Ce_0.8Ca_0.2O_1.8-3 fibers (sample 4, 0.6 wt%) present the best interfacial bonding strength with modified bisphenol A cyanate (BADCy) resins, the single fiber pull-out strength between sample 4 and modified BADCy resins reaches the maximum value of 4.6 MPa, 48.4% higher than that of pristine PBO fibers (sample 0, 3.1 MPa). Meanwhile, the tensile strength of sample 4 after 288 hours UV aging is increased from 1.4 GPa (PBO fibers) to 4.1 GPa. Overall, functionalized PBO fibers in this work demonstrate higher surface activity, excellent UV resistance and improved interfacial bonding strength with modified BADCy resins, which provides a new idea for functionalizing the surface activity and UV resistance of high-performance polymer fibers.

聚对苯撑苯并二噁唑（PBO）纤维具有较差的耐紫外线性能和表面化学惰性。本研究通过化学共沉淀法制备氧化钙掺杂氧化铈（Ce_0.8Ca_0.2O_1.8） 纳米颗粒，进而设计Ce_0.8Ca_0.2O_1.8/P(S-co-BCB-co-MMA)有机-无机杂化涂层用于改性PBO纤维（PBO@P-Ce_0.8Ca_0.2O_1.8）。结果表明，Ce_0.8Ca_0.2O_1.8纳米颗粒的粒径约为50 nm；PBO@P-Ce_0.8Ca_0.2O_1.8-3纤维（样品4，0.6 wt%）与改性双酚A氰酸酯（BADCy）树脂具有最佳的界面粘结强度，其单丝拔出强度达到最大值（4.6 MPa），比纯PBO纤维与改性BADCy树脂的单丝拔出强度（3.1 MPa）高48.4%。同时，样品 4在紫外老化288小时后的拉伸强度从1.4 GPa（纯PBO纤维）增加到4.1 GPa。本研究获得的改性PBO纤维具有更高的表面活性、优异的耐紫外线性能以及与改性 BADCy树脂具有更佳的界面粘结强度，为PBO纤维的表面功能化改性和提高其耐紫外线性能提供了新思路。