Polyvinylidene fluoride powder modifying method
The invention relates to a preparation method of modified polyvinylidene fluoride powder, and belongs to the field of membrane materials. The preparation method comprises the following steps: firstly dispersing polyvinylidene in an organic alkali alcoholic solution in nitrogen atmosphere, stirring, reacting for a period of time, filtering, washing by using an alcoholic solution, heating in nitrogen atmosphere, and drying so as to obtain the required modified polyvinylidene fluoride powder without hydrogen fluoride. The modified polyvinylidene fluoride powder prepared by the method has relatively good active sites such as carbon-carbon double bond and is convenient for large-scale production. 1. Polyvinylidene fluoride powder modified method, characterized in that comprises the following preparation method : (1) measure a quality pvdf powder dispersed in the methanol solution, wherein each gram of methanol solution of polyvinylidene fluoride to 5-10mL, ultrasonic 5 min, A shall suspension ; (2) according to the suspension with A 2.77mol/L quaternary ammonium alkali methanol solution volume ratio of 30:3-5, quantity takes the quaternary ammonium alkali to be mellow solution, adding suspension in A, stirring in a nitrogen atmosphere, to make suspension B, 20 min to obtain brown powder suspension, will be precipitated and filtered, filtered, repeatedly washed with anhydrous methanol, dried to obtain brown modified polyvinylidene fluoride powder. 2. Polyvinylidene fluoride powder modified according to Claim 1 of the new method, which is characterized in that the added organic alkali comprises tetramethyl ammonium hydroxide or ammonium tetraethyl hydroxide. 3. Polyvinylidene fluoride powder modified new method according to Claim 1, characterized in that the step (2) alcohol including methanol or ethanol solvent. 4. Polyvinylidene fluoride powder modified new method according to Claim 1, characterized in that the step (2) in the concentration ammonium alkali B quarter of the concentration of the suspension in 0.2-0.4mol/L.