| In this work, polyacrylonitrile (PAN) hollow fibers as precusor were oxidized in air, carbonized in nitrogen, activated with carbon dioxide. The effects of the oxidation, carbonization and activation conditions on the structure and properties of the resultant PAN-based activated carbon hollow fibers (PAN-ACHF) were studied. There are a lot of micropores and mesopores in the resultant PAN-ACHF which has high surface area and high adsorption ratios to iodine and methyleneblue. Moreover, the structure, properties, reaction mechanism and pore structure token of PAN-based oxidation fibers, carbonization fibers and activation fibers were tested by some testing ways such as FTIR, SEM, DSC, X-diffraction, element analyzing and auto-adsorption apparatus and so on. The research is as follows:1. Effects of oxidation condition on the structure and properties of PAN oxidation hollow fibers (PAN-OHF) and PAN-ACHF were studied during the process of oxidation, and the best oxidation condition was chosen. The results show that the best oxidation condition is 250℃ for 2hr and the heating ratio is 5℃/min. The adsorption capacities to iodine and methyleneblue increase with oxidation temperature increasing and oxidation time extending, then decrease. The activation yield obviously increases and adsorption capacities to iodine and methyleneblue change little with heating ratio decreasing.2. Effects of carbonization condition on the structure and properties of PAN-ACHF were studied during the process of carbonization, and the best carbonization condition was chosen. The results show that the best carbonization condition is 900℃ for 60min and the heating ratio is 30℃/min. The specific surface area and adsorption capacities to iodine and methyleneblue increase with carbonization temperature, and reach maximum when carbonization temperature is 900℃, then decrease. Moreover, the specific surface area and adsorption capacities to iodine and methyleneblue reach maximum when carbonization time is 60min. Theactivation yield obviously decreases and adsorption capacities to iodine and methyleneblue increases with heating ratio increasing.3. Effects of activation condition with C02 on the structure and properties of PAN-ACHF were studied during the process of activation, and the best activation condition was chosen. The results show that the best activation condition is 950°C for 60min. The effect of activation temperature and time on the activation yield, the specific surface area and adsorption capacities is obviously, the specific surface area and adsorption capacities reach maximum when activation temperature is 950 °C. The effect of activation time on the structure and properties is also important. Increasing activation temperature is same as extending activation time.4. Effects of activation condition with KOH on the structure and properties of PAN-ACHF were studied during the process of activation, and the best activation condition was chosen. The results show that the best activation condition is dipping time is 12hr, concentration of KOH solution is 50% (wt%), activation temperature is 850°C, and activation time is 60min. The specific surface area and adsorption capacities to iodine and methyleneblue increase with the concentration of KOH solution increasing. The specific surface area of PAN-ACHF activated with KOH increases with activation temperature increasing, and reaches maximum (2000m2/g) when activation temperature is 850°C, then decreases little. Compared with activation process with CO2, activation process with KOH results in larger surface area and adsorption capacities of PAN-ACHF.5. The token about pore structure of PAN-ACHF with two activation ways including activation with CO2 and KOH was studied. The specific surface area and pore volume of PAN-ACHF obviously increase with activation temperature increasing and activation time extending. However, the difference about pore diameter is little and the most of pore is micropore whose pore diameter is smaller than 2nm, and the largest pore diameter is about 0.8nm for activation with KOH. The porediameter distribution of PAN-ACHF activated with CO2 is similar to that activated with KOH, and pore diameter is about 2.2nm. Air and nitrogen glow discharge were used to replace chromic acid pretreatment todeposit copper film on carbon fiber surfaces from an CuSCVHCHO electroless system. A greater copper uptake and a more uniformly coated copper film were obtained for plasma-treated carbon fibers. The adhesion between the copper film and the carbon fibers was also improved. An orthogonal table L9(34) was used to study the effects of discharge pressure, discharge power, time and gas kind on the copper uptake. Scanning electron microscopy (SEM), X-ray photoelectron spectroscopy (XPS) at different depths were applied to characterize the surface physical and chemical changes of the carbon fibers.
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