| 摘要 |
PURPOSE:To reduce initial filtration pressure but to increase permeation capacity for water by allowing a three-dimensional net work of polyolefin or fluorine- contg. resin to contain 10-70wt% hydrophilic inorg. particles having 0.005-5mu mean particle size. CONSTITUTION:Hydrophobic resin such as polyolefin resin e.g. polyethylene, polypropylene, etc., or fluorine contg. resin such as polyvinylidene fluoride resin is used. For example, a mixture consisting of 7-42vol% hydrophilic inorg. powder, 30-75vol% org. liquid plasticizer having 84-99 solubility parameter and 10-60vol% polyolefin having <300.000 weight average mol.wt. and >=15,000 number average mol.wt. is fusion-moulded. Fine porous membrane is obtd. by extracting the liquid org. plasticizer from the fusion-moulded product. Suitable hydrophilic inorg. particle is one being water-insoluble having <=5mu particle size, among silica, MgO, alumina, BaSO4, etc. |
