초록 ▼

Improved ultraporous and microporous membranes are provided with an entirely reticulated structure free of large finger voids. The reticulated support structure has gradually increasing pore size which reaches a maximum of from about 10 to about 20,000 times the diameter of the skin pores at the opp

Improved ultraporous and microporous membranes are provided with an entirely reticulated structure free of large finger voids. The reticulated support structure has gradually increasing pore size which reaches a maximum of from about 10 to about 20,000 times the diameter of the skin pores at the opposite face. The skin is very thin and has controllable highly uniform skin pores of from about 0.003 to about 3.0 microns in diameter. The structure offers highly desirable properties to such membranes.

대표청구항 ▼

An asymmetric integral polymer membrane having a bulk porosity greater than seventy percent, a skin face an an opposite face comprising: A. A porous skin having skin pores with an average diameter of from about 0.003 to about 3.0 microns; and B. A porous support comprising a substantially continuous

An asymmetric integral polymer membrane having a bulk porosity greater than seventy percent, a skin face an an opposite face comprising: A. A porous skin having skin pores with an average diameter of from about 0.003 to about 3.0 microns; and B. A porous support comprising a substantially continuous reticular mass of a thress-dimensional network defining interconnecting flow channels communicating with said skin pores and with said opposite face, said flow channels defining support pores having diameters generally increasing gradually in size from said skin to said opposite face, to an average diameter of from about 10 to about 20,000 times the diameter of said skin pores, and said support being substantially free of voids materially larger in diameter than said gradually increasing support pores.