Manager Hao (pre oxygenation thread): 13831164999
Manager Shi (pre oxygenation wire): 17332928150
Manager Gu (Pre oxygenation Silk): 13833138900
Manager Zhao (woven fabric, pre impregnated fabric, prefabricated body): 15028196018
Manager Zhang (woven fabric, axial fabric): 13703314888
Manager Zhao (Composite Products): 13944687090
Address: 226 Shifu East Road, Gaocheng District, Shijiazhuang City, Hebei Province
Pre-oxidized fiber will undergo aging during storage and use, which is mainly reflected in structural brittleness, surface property degradation, and reduced carbon yield—these changes will directly affect the quality of the final carbon fiber or the performance of its direct applications (e.g., flame-retardant components). The aging process is essentially the result of the fiber’s chemical structure and physical properties being damaged by external environmental factors.
Below are the main factors affecting the aging of pre-oxidized fiber, tailored for industrial application scenarios:
Pre-oxidized fiber has a large number of oxygen-containing functional groups (e.g., -COOH, -OH) on its surface, which are highly reactive and prone to continuous oxidation reactions with oxygen in the air.
Aging manifestations: The cross-linked structure of the fiber is further destroyed, the fiber becomes brittle and easy to break, and the tensile strength retention rate decreases by 20–30% after long-term exposure to air. For pre-oxidized fiber used in carbon fiber production, excessive oxidation will reduce the carbon yield by 5–10%.
Key influencing conditions: High oxygen concentration and high temperature will accelerate the oxidation rate. For example, storing pre-oxidized fiber in an open environment at 30°C will cause obvious oxidation aging within 1 month, while low-temperature sealed storage can delay this process for 6–12 months.
Pre-oxidized fiber is hygroscopic, and moisture in the air will penetrate into the fiber’s internal structure and trigger hydrolysis reactions.
Aging manifestations: The oxygen-containing groups on the fiber surface react with water molecules, causing the interface between the molecular chains to loosen, the fiber to become soft and lose rigidity, and the structural uniformity to decrease. When used for carbonization, hydrolyzed pre-oxidized fiber is prone to bubble defects in the final carbon fiber.
Key influencing conditions: High humidity (relative humidity >60%) is the main trigger. For example, pre-oxidized fiber stored in a coastal high-humidity environment will absorb moisture and hydrolyze within 2 weeks, while storage in a dry environment (RH <40%) can effectively inhibit hydrolysis.
Temperature changes will cause thermal expansion and contraction of the pre-oxidized fiber’s internal structure, leading to microcracks and accelerating aging.
Aging manifestations: Repeated high-low temperature cycles (e.g., day-night temperature difference, seasonal temperature changes) will cause the cross-linked molecular chains of the fiber to fatigue and break, forming microcracks on the surface. These cracks become channels for oxygen and moisture to enter, further exacerbating oxidation and hydrolysis.
Key influencing conditions: Large temperature differences (>15°C) and frequent temperature changes are more damaging than constant high temperatures. For example, pre-oxidized fiber stored outdoors with large temperature fluctuations will have a surface defect rate of >15% after 3 months, while constant low-temperature storage can keep the defect rate below 2%.
UV light has high energy and can break the chemical bonds of the pre-oxidized fiber’s molecular structure, especially the conjugated double bonds that maintain structural stability.
Aging manifestations: The fiber surface turns yellow and becomes rough, the internal cross-linked structure is damaged, and the toughness decreases significantly. For pre-oxidized fiber used directly as flame-retardant fabrics, UV aging will reduce its flame-retardant performance and heat insulation efficiency.
Key influencing conditions: Direct sunlight is the main source of UV radiation. Pre-oxidized fiber exposed to sunlight for 1 month will have a tensile strength loss of >30%, while dark storage can completely avoid UV-induced aging.
During storage and use, mechanical stress or physical friction will cause structural damage to the pre-oxidized fiber and accelerate aging.
Aging manifestations: Excessive stacking pressure will cause the fiber to deform and wrinkle; friction during handling will scratch the fiber surface and form microcracks. These mechanical damages provide entry points for oxygen and moisture, leading to localized accelerated aging.
Key influencing conditions: Improper handling (e.g., dropping, stacking too high) and rough contact with hard objects are the main triggers. For example, pre-oxidized fiber rolls stacked with more than 5 layers will have obvious deformation and surface damage within 1 month, while flat storage with ≤3 layers can avoid this problem.
In industrial environments, pre-oxidized fiber may come into contact with chemical contaminants (e.g., acidic fumes, alkaline dust, organic solvents), which will react with the fiber and cause targeted aging.
Aging manifestations: Acidic contaminants will corrode the fiber’s surface functional groups, leading to brittleness; alkaline contaminants will destroy the cross-linked structure, causing the fiber to decompose; organic solvents will swell the fiber and reduce its structural stability.
Key influencing scenarios: Pre-oxidized fiber used in chemical plants or industrial workshops with corrosive gases is more prone to this type of aging.
The aging of pre-oxidized fiber is a comprehensive result of oxygen, moisture, temperature, UV radiation, and mechanical factors. To slow down aging, the core measures are sealed vacuum packaging, low-temperature dry storage, and avoiding mechanical damage—these can effectively extend the service life of pre-oxidized fiber by 3–5 times.
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Ltd. All rights reserved.
Manager Hao (Pre-oxidized Fiber): 13831164999,hjh@hbtangu.com
Manager Shi (Pre-oxidized Fiber): 17332928150,sj@hbtangu.com
Manager Gu (Pre-oxidized Fiber): 13833138900
Manager Zhao (Woven Cloth, Prepreg Cloth, Preform): 15028196018,zb@hbtangu.com
Manager Zhang (Woven Cloth, Axial Cloth): 13703314888
Manager Zhao (Composite Products): 13944687090, zqy@hbtangu.com
Email: hbtg@hbtangu.com
Address: No. 226, East Shifu Road, Gaocheng District, Shijiazhuang City, Hebei Province
