Abstract: The present invention relates to a method of forming air holes in a hollow fiber membrane module for water treatment. A main object of the present invention is to easily form air holes in the potting material injected into the module housing to prevent contamination of the hollow fiber membranes in the module housing.

Abstract: The present invention relates to a polyvinylidene difluoride hollow fiber membrane and a method of preparing the same, and more particularly, to an improved polyvinylidene difluoride hollow fiber membrane and a preparation method thereof, in which a spinning solution consisting of polyvinylidene fluoride, alcohol dendrimer and organic solvent is prepared, and then is subjected to solidification by a wet-phase transition process, cleaning and drying, in which alcohol dendrimer that is an organic material as a pore former is introduced, allowing uniform disperse of alcohol dendrimer in polyvinylidene difluoride to form pores, with each having a high dispersion ability and a uniform size, and in which an excellent adhesion durability is imparted, owing to the use of a single material of polyvinylidene difluoride, unlike the conventional hollow fiber membrane preparation method in which pores are formed using existing inorganic particles.