METHOD OF PREPARING POROUS MATERIAL Russian patent published in 1997 - IPC

FIELD: manufacture of filters for cleaning liquid and gaseous substances, materials for encapsulation of repellants, toxic agents and aromatic compounds. SUBSTANCE: porous materials is molded from composition containing 2-3% aqueous cellulose suspension and filler. The filler is thermoplastic polymer with particle size of 0.01-1.0 mm (in amount of 10-50 wt % per 100 wt % composition) or mixture thereof with 5-40% mineral filler (per 100 wt % composition) with particle size of 0.04-0.5 mm which is selected from the group consisting of zeolite, shuntite and apatite. Molded material is further dehydrated by vacuum treatment at pressure of 0.3-1.0 kg/1 sq. cm. Drying is carried out at 80-90 C for 10-20 minutes. The material is then heat treated with air or steam at melt temperature of thermoplastic polymer for 10-20 minutes. Prior to drying one of the material sides is coated with vinyl chloride-vinylidene chloride latex in amount of 2.7- 3.3 wt.-% material. EFFECT: more efficient preparation method. 2 cl, 1 tbl