Method for preparing porous mullite fiber through coaxial electrostatic spinning

Abstract

The invention relates to a method for preparing porous mullite fiber through coaxial electrostatic spinning and belongs to the science and technology technical field of materialsmaterial science. The fiber preparing method comprises the following steps: preparing anhydrous aluminum chloride, tetraethoxysilane, isopropyl ether and anhydrous dichloromethane into a reaction solution according to a certain molar ratio, then heating the reaction solution, triggering non-hydrolytic sol-gel reaction to synthesize mullite gel; mixing absolute ethyl alcohol and a certain amount of polyvinylpyrrolidone (PVP) according to a certain ratio to obtain a PVP ethanol solution, dissolving the synthesized mullite gel in the PVP ethanol solution, then adding N,N-dimethylformamide (DMF) to obtain a spinning precursor solution; taking liquid paraffin as an inner solution, taking the mullite precursor solution as an outer solution, preparing mullite gel / PVP composite fiber through a coaxial electrostatic spinning process, then calcining the mullite gel / PVP composite fiber under high temperature to obtain the porous mullite fiber. The preparation method of the porous mullite fiber is simple; the porous structure is easy to control; the porous mullite fiber has excellent heat insulation and heat preservation properties; a novel high-temperature heat insulation material is provided for the fields such as aviation and military industry and the like.

Description

technical field

[0001] The invention belongs to the field of preparation of mullite fibers, in particular to a method for preparing porous mullite fibers by coaxial electrospinning. Background technique

[0002] Mullite (3Al 2 o 3 2SiO2 2 ) fiber is considered to be an excellent ceramic material because of its excellent high temperature strength, high temperature creep resistance, thermochemical stability, low thermal expansion coefficient and good dielectric properties. The use temperature of mullite fiber is as high as 1500 ℃, and the tensile strength is about 2.1GPa, which is the same as that of A1 2 o 3 Fiber quite. At the same time, it also has better oxidation resistance than carbon and silicon carbide fibers. Therefore, mullite fibers are widely used in metallurgy, aerospace instrument insulation, and reinforcement of composite materials.

[0003] At present, mullite fibers are usually prepared by micropowder extrusion method, centrifugal spinning method, pullin...