PREPARATION METHOD FOR HOMOGENEOUSLY-ENHANCED POLYVINYLIDENE FLUORIDE HOLLOW FIBER MEMBRANE

摘要

Disclosed is a preparation method for a homogeneously-enhanced polyvinylidene fluoride hollow fiber membrane. The preparation method comprises the following processes: 1. preparing a reinforced body base membrane: taking a polyvinylidene fluoride hollow fiber membrane as the reinforced body base membrane; 2. preparing a polyvinylidene fluoride membrane casting solution, which comprises the following components in percentage by mass: 6-20 percent of polyvinylidene fluoride, 0.6-2 percent of hydrophilic polymer or hydrophilic inorganic particle, 6-10 percent of pore-forming agent, and 68-87.4 percent of solvent; mixing various components in a water bath of 70-90°C, stirring the components for 3-4 hours and dissolving; and vacuum defoaming to obtain the membrane casting solution; and 3. preparing a homogeneously-enhanced membrane: uniformly coating the membrane casting solution to the surface of the reinforced body base membrane through a spinneret for spinning; then spinning the base membrane to form a membrane under the traction of a silk guide roller; and solidifying the membrane with ultrafiltration water through an air gap with the length being 5-20 cm to obtain the homogeneously-enhanced membrane, the traction speed being 5-25 cm/min.