Ion exchanger - polyolefin membranes

Claim 2

A PROCESS FOR PRODUCTION ION EXCHANGERS WHICH COMPRISE MIXING AN ION EXCHANGE RESIN IN POWDER FORM AND A POLYOLEFIN RESIN IN A WEIGHT RATIO OF FROM 8:2 TO 2.5:7.5, KNEADING AND SHAPING THE RESULTING MIXTURE AT A TEMPERATURE AT WHICH THE POLYOLEFIN RESIN SOFTENS AND MELTS, AND AT WHICH THE ION EXCHANGE RESIN RETAINS ITS SHAPE, AND SUBJECTING THE ARTICLE THUS SHAPED TO TREATMENT IN HOT WATER AT A TEMPERATURE FROM 80*C TO THE SOFTENING POINT OF THE SHAPED ARTICLE FOR A PERIOD OF FROM A FEW MINUTES TO SEVERAL HOURS.

Claim 3

A process for producing ion exchangers as claimed in claim 1 in which the ion exchange resin in powder form has a particle size passing through a 100-mesh Tyler standard sieve.

Claim 4

A process for producing ion exchangers as claimed in claim 1 in which the polyolefin resin is a polymer of an .alpha.-olefin selected from the group consisting ethylene, propylene, and butene-1.

Claim 5

A process for producing ion exchangers as claimed in claim 3 in which the polyolefin resin is polyethylene.

Claim 6

A process for producing ion exchangers as claimed in claim 1 in which the hot water is substantially neutral.

Claim 7

A process for producing ion exchangers as claimed in claim 1 in which the article thus shaped is a thin-walled article.

Claim 8

A process according to claim 1 wherein said polyolefin resin is selected from the group consisting of .alpha.-olefin homopolymers of ethylene, propylene and butene-1 and copolymers of not less than 70 wt percent of said .alpha.-olefins with the remaining part of a vinyl monomer.

Claim 9

A process for producing ion exchangers according to claim 1 comprising a polyolefin resin having a fine net-like structure dispersed uniformly throughout a shaped article and an ion exchange resin in powder form enveloped within each of minute cells of said net-like structure, which process comprises mixing an ion exchange resin having a swelling property in hot water in powder form and a polyolefin resin having a softening point lower than that of said ion exchange resin and stretchability at a temperature of 80.degree. - 100.degree.C. with a weight ratio of from 8:2 to 2.5:7.5, kneading and shaping the resulting mixture at a temperature at which the polyolefin resin softens and melts, and at which the ion exchange resin retains its shape, and subjecting the article thus shaped to treatment in hot, substantially neutral water at a temperature of from 80.degree.C to a temperature at which the shaped structure begins to undergo remarkable deformation for a period of from a few minutes to several hours.