TY  - JOUR
A1  - Reiche, Jürgen
A1  - Kamusewitz, Helmut
A1  - Keller, Manuela
A1  - Brehmer, Ludwig
A1  - Peñacorada, Florencio
T1  - Study of gas transport through composite membranes with a stabilised Langmuir-Blodgett skin layer
N2  - The Langmuir-Blodgett (LB-) technique is used to deposit molecular reinforced separation layers on porous polymer substrates resulting in composite membranes for gas separation. The adsorption of a polycation to the arachidic acid Langmuir layer and the subsequent transfer of the highly ordered and stabilised monolayer onto a polypropylene membrane (Cellgard 2400) yields a laminated separation layer combining the advantageous high degree of order of fatty acid films and the stability of thin polymeric films. X-ray reflectivity data of these films confirm the transfer of the assembled polymer layer together with the fatty acid monolayer and the formation of ordered Y-type LB-films. SFM pictures show a dense film without pinholes completely covering the porous support. Gas permeation measurements are used to study the transport process of different gases through the composite membrane.
Y1  - 1995
ER  - 
TY  - JOUR
A1  - Penacorada, Florencio
A1  - Angelova, Angelina
A1  - Kamusewitz, Helmut
A1  - Reiche, Jürgen
A1  - Brehmer, Ludwig
T1  - Scanning Force Microscopy and Wetting study of the Surface Modification of a Polypropylene Mambrane by Means of Langmuir-Blodgett Film Deposition
N2  - Polypropylene membranes with deposited ultrathin "siin" layers are attractive for separation and cleaning of gaseous mixtures. In the present study, the surface morphology and wetting hysteresis of composite membranes consisting of a microporous polypropylene support and Langmuir-Blodgett ("skin") films, are investigated. The effect of the interlayer molecular interactions and the substrate features on the integrity and homogeneity of the "skin" layers is examined. Langmuir-Blodgett films of arachidic acid and cadmium and calcium arachidate are characterized both on smooth silicon and on porous polypropylene supports. Contact angle measurements and scanning force microscopy (SFM) are applied for investigations of the membrane surface modification upon transfer of a different number of monolayers. It was found that the contact angle hysteresis of the bare membrane decreases after the LB-deposition of close-packed monolayers. Smoothing of the membrane surface is also evidenced by the SFM images, on different length scales, confirming a good coverage of the membrane pores.
Y1  - 1995
ER  - 
TY  - JOUR
A1  - Angelova, Angelina
A1  - Penacorada, Florencio
A1  - Stiller, Burkhard
A1  - Zetzsche, Thomas
A1  - Ionov, Radoslav
A1  - Kamusewitz, Helmut
A1  - Brehmer, Ludwig
T1  - Wettability, surface morphology and stability of long chain ester multilayers obtained by different Langmuir- Blodgett deposition type
Y1  - 1994
ER  -