针对静电纺丝SiC纤维纳米化的溶液参数优化设计

One dimensional SiC nano-materials not only hold high strength and modulus, exceeding chemical stability and high temperature resistance, but also bear large specific surface area, controllable microstructure and dielectric properties, which enable the exceptional application value of 1D SiC nano-materials in the sector of electromagnetic absorption. Electrospinning is generally recognized as an effective approach to fabricate continuous SiC nanofibers. At present, the preparation of SiC ceramic fibers by electrospinning is still in the preliminary stage of exploration, there is a confusion in adaptable spinning solutions and their parameters, as well as a lack of systematic study, especially in optimization of solution aiming at preparing nanoscale SiC fibers by electrospinning. In this study, we took the polycarbosilane (PCS) solution, the precursor for electrospun SiC nanofibers, as research object, analyzed the effects of the kinds of solvents, type and concentration of polymer spinning aid, ratio and viscosity of the solution, types and amounts of additives on the morphology and microstructure systematically. Accordingly, we confirmed the sa-tisfactory solvent-spinning aid-additive system that include solvent chloroform, spinning aid polycaprolactone (PCL) and addictive hafnium acetone (Hf(acac)₄). To prepare nanoscale SiC fibers with continuous microstructure and uniform morphology, the optimal concentration of PCL was 0.087 5 g/mL, the concentration range of PCS was 0.125-0.15 g/mL, and the addition amount of Hf(acac)₄ should not exceed 0.025 g/mL. Consequently, the flexible SiC nanofibers with the average diameter of 340 nm were successfully obtained after optimization of spinning solution.