Tubular PEBA/Ceramic Nanocomposite Hybrid Membranes for Gas Sweating

Poly(ether-block-amide) (PEBA) is a thermoplastic elastomer comprising of hard and soft segments of polyamide (PA) and polyether (PE) respectively. The polymer structure consists of a linear chain of polyamide segments interspaced with polyether segments, having the following general chemical formula: In this segmented block copolymer, there are two microphase-separated domains: the polyamide crystalline domains provide mechanical strength and the polyether amorphous domains offer high permeability due to the high chain mobility of the ether linkage [1]. Membranes made from certain grades ofPEBA polymers exhibited good performance for separation of polar (or quadrupolar)/nonpolar gas pairs(CO2/N2, SO2/N2 or CO2/H2) [2, 3]. Asymmetric composite membranes consisting of a thin separation layer and a microporous support are used in almost all industrially important gas separation processes. The dense layer was responsible for the separation, while the porous sub-layer provided mechanical strength to the selective layer with minimum resistance to the permeation of components [4]. The major drawbacks of organic-organic hybrid membranes are low pearmeability, low mechanical, chemical and thermal stability [5]. Therefore, high performance hybrid membranes could be only obtained by using asymmetric multilayer porous ceramic supports. This kind of membranes is called organic-inorganic hybrid membranes [4]. In this work, a new PEBA copolymer based on nylon6 and poly(ethylene oxide) is synthesized with multi-block structure. Multilayer porous ceramic supports are prepared with controllable microstructures using nanocomposites technology. Then PEBA/ceramic nanocomposite membranes are fabricated by dipcoating of ceramic porous support in PEBA solution. Membranes were examined by pure gases (CO2 & N2) permeation tests.