Preparation And Properties Of Nano-SiO₂ Composite Antioxidant/Polyphenylene Sulfide Fiber

Polyphenylene sulfide?PPS?fiber is one of the main raw materials for exhaust gas dust filter materials in high temperature and complex fields such as thermal power generation,steel and waste incineration due to its excellent chemical resistance,excellent mechanical properties and excellent flame retardancy.However,PPS fibers are easy to be oxidized under high temperature aerobic environment,resulting in yellowing and brittleness,inactivation of filter bags and reduction of service life,which severely limits their application fields.In this paper,according to the processing technology of PPS fiber and the requirements of high temperature and complex environment,a high temperature resistant antioxidant quercetin was selected to improve the oxidation resistance of PPS fiber.Then,based on the research of the research group,nano SiO₂ and quercetin compound modified PPS fiber.And nano-composite antioxidant modified PPS fiber prepared with nano SiO₂ supported antioxidant AO.The synergistic antioxidant mechanism of nano-SiO₂ and antioxidant on PPS was proposed in the study of the properties of modified PPS fibers,which provided a new theoretical basis and scientific basis for improving the antioxidant ability of PPS fibers.The main contents of this paper are as follows:?1?Quercetin/PPS composite masterbatches and fibers with different contents were prepared by twin screw extruder and melt spinning machine.The crystallinity,thermal stability,oxidation resistance,spinnability and high temperature oxidation resistance of quercetin/PPS masterbatches and fibers were studied by DSC,TGA,SEM and dynamic OIT.The results showed that the spinnability of quercetin/PPS composite fibers was excellent;the antioxidant activity of quercetin to PPS fibers was significantly improved.When the content of quercetin was 0.2 wt.%,the effect was the best,the dynamic OIT reached467.3 C,which was 14.9 C higher than that of pure PPS fibers.?2?Based on the research of Q/PPS composite fibers and nano SiO₂ before the research group,nano SiO₂/Q/PPS composite masterbatch and fiber with nano SiO₂ content of 1.0 wt.%and different quercetin content were prepared,and their properties were studied.The results showed that the crystallinity,tensile strength,thermal stability and oxidation resistance of PPS and quercetin/PPS composite fibers were significantly improved by adding nano-SiO₂.When the content of quercetin was 0.2 wt.%,the crystallinity increased by 13.8%,the tensile strength increased by 46.65%,the 5%weight loss decomposition temperature increased by 12.68%,the dynamic OIT reached471.7°C,and 360 h after heat treatment at 220°C,the tensile strength retention rate reached 85.76%.?3?The nano-composite antioxidant nano SiO₂-g-AO was prepared by nano-SiO₂ loaded antioxidant AO and its structure and properties were analyzed.The results showed that the antioxidant AO was successfully loaded on the surface of nano SiO₂,and the loading ratio was 5.5%;nano SiO₂-g-AO has excellent heat resistance and meets the requirements of processing and use of PPS;the self-agglomeration phenomenon of nano SiO₂-g-AO is obviously reduced and the dispersibility is improved.?4?The effects of nano SiO₂-g-AO with different content on the crystallinity,thermal stability and oxidation resistance of PPS composite masterbatches and fibers were studied.The results showed that the dispersion effect of nano SiO₂-g-AO in PPS matrix is better than that of nano-SiO₂;the spinnability of nano SiO₂-g-AO/PPS composite fibers is better on the whole;nano SiO₂-g-AO improves the crystallinity,thermal stability,mechanical properties and oxidation resistance of PPS fibers.When the content was 2.0wt.%,the crystallinity of composite fiber increased by 21.98%,tensile strength increased by 49.70%,dynamic OIT reached 473.5°C,and the strength retention rate reached 86.97%after aerobic treatment at 220°C.The antioxidant mechanism of the composite fibers was discussed,which provided a theoretical basis for the improvement of PPS fibers by nano composite antioxidants.