| Among the universal polymer materials of gas separation membrane, silicone rubber (PDMS) has always been focused just because of its highest oxygen permeability PO2 (600 barrer). However, its separation coefficient ( =2) and membrane formability are bad, which limited its practical value.The PDMS membrane with high vinyl content was formed by vulcanization at room temperature in this research. Firstly, the influences of membrane forming conditions (for example, the contents of crosslinking regent, membrane-forming and testing temperature) on PO2 and O2/N2 were tested. Secondly, 11-alkene acid and 11-alkene acid cobalt were introduced into the crosslinking net structure of PDMS membranes. And the effects of additives quantities, pressure difference and testing temperature on Po2 and O2 / N2 were investigated detailedly.The research results showed that, the soft crosslinking membrane with good testing property was gained by the simple method of simultaneous membrane formation and crosslinking reaction. For silicone membrane with high vinyl content, in some range, higher crosslinking regent content and lower vulcanization and testing temperature leaded to higher o2/N2 (the highest value is 2.33) but lower PO2. The addition of 11-alkene acid into membranes improved O2/N2 to some extent (O2/N2 is 2.4 when 11-alkene acid content is 5wt%), but PO2 also decreased. Compared to above contradiction of Po2 and o2 / N2, the introduction of 11-alkene acid cobalt (II) improved both Po2 and O2:/N2 at the same time under the condition of low pressure difference. With the increase of 11-alkene acid cobalt quantities, the highest O2/N2 added up to 3.44. The good results came from the facilitated transport of 02 by the formation of cobalt ion macro complex, which was testified by ESR chart.
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