(US4759776-A)      Novel polytrialkylgermylpropyne polymer has formula (I). R1 is H, Me or Et; R2 and R3 are each linear or branched (1-6C) alkyl; R4 is linear or branched (1-12C) alkyl or aryl; X is (1-3C) alkyl or Ph; m is 100 or more; and n is 0 or 1.    Prepn. comprises polymerising corresp. monomers of (I) and casting it into a membrane form.    Opt. a copolymer is used contg. structural units of formula (I) with 1 or more different comonomers, either in alternating, block or random configuration.    USE -   As membrane for gas espn., liq. sepn., pervaporation, or ultrafiltration.    (10pp)    (JP92060693-B)      A polymer of formula (I) (where R1 = H or 1-2C alkyl gp. (pref. methyl); R2,R3 = linear or branched 1-6C alkyl (pref. methyl); R4 = linear or branched 1-2C alkyl or aryl (pref. methyl); X = 1-3C alkyl, phenyl; m = at least 100, n = 0 (pref.) 1; and opt. one or more different copolymerisable monomers in a random, block or alternating congfiguration is pref. cast in membrane for (pref.) subsequent ultraviolet or electromagnetic treatment, or treatment in a plasma field. It is employed in gas sepn., liq. sepn., pervaporation or ultrafiltration operations.    A treated, semi-permable, polymeric membrane having improved selectivity for use in sepg. components of a gas feed mixt. comprises above polymer cast into membrane form, which has been treated (pref. at ambient temp. and pressure) with a reactive source of fluorine (pref. a gas stream contg. 0.01-25% (pref. 0.1-2%) fluorine gas) for a time sufficient to modify the membrane such that the 02/N2 selectivity ratio of the membrane is increased by at least 50% over that of the membrane prior to treatment with the reactive fluorine source (pref. 10 seconds-24 hours, more pref. 0.5-120 minutes).    ADVANTAGE -   These membranes exhibit high permeability for a wide range of gases, increased selectivity of the membrane can be achieved for a wide variety of gas streams which contain at least 2 components having different permeability rates through the membrane. (J63171619-A)    (SU1741609-A3)      A polymer of formula (I), where R1 = H or 1-2C alkyl gp., (pref. methyl) R2, R3 = linear or branched 1-6C alkyl (pref. methyl), R4 = linear or branched 1-12C alkyl or aryl (pref. methyl); X = 1-3C alkyl, phenyl, m = at least 100, n = 0 (pref.) 1; and opt. one or more different copolymerisable monomers in a random, block or alternating configuration; is pref. cast in membrane form (pref. subsequently treated to ultraviolet or electromagnetic treatment, or treated in a plamsa field) and employed in gas sepn. liq. sepn. pervaporation or ultrafiltration operations.    A treated, semi-permeable, polymeric membrane having improved selectivity of use in sepd. components of a gas feed mixt. comprises above polymer cast into membrane form, which has been treated (pref. at ambient temp. and pressure) with a reactive source of fluorine (pref. a gas stream contg. 0.01-25% (pref. 0.1-2%) fluorine gas) for a time sufficient to modify the membrane such that the O2/N2 selectivity ratio of the membrane is increased by at least 50% over that of the membrane prior to treatment with the reactive fluorine source (pref. 10 seconds-24 hours, more pref. 0.5-120 minutes).    ADVANTAGE -   These membranes exhibit high permeability for a wide range of gases, increased selectivity of the membranes can be achieved for a wide variety of gas streams which contain at least 2 components having different permeability rates through the membrane. Bul.22/15.6.92