Effects of Light Stabilizer on the Mechanical Properties of Poly-p-phenylenebenzobisoxazole Fibers under Sunlight Irradiation

In this work, light aging resistant PBO fiber containing light stabilizer (OB-1) was prepared via in-situ polymerization and dry-jet wet-spinning process. The mechanical properties of the fibers under sunlight radiation were investigated by tensile testing. PBO fiber is sensitive to both UV light and sunlight, and undergoes severe degradation under light exposure. After exposed to sunlight and sunlight sealed from humidity for 318h the strength retention is only 25.39% and 33.08%, respectively. The light stability of PBO can be enhanced with only a small amount (0.05-0.2%) of addition of OB-1. Under the same conditions the strength retention of 0.2%OB-1/PBO fiber is 55.52% and 64.84%, which is 119% and 96% higher than that of PBO fiber.