In situ ATR-FTIR and SFM Studies on the Influence of Adsorption time on Deposition and Nanostructure of Poly(ethyleneimine)/Poly(acrylic acid) Multilayers

• Published in: Macromolecular symposia Vol. 265; no. 1; pp. 77 - 88
• Main Authors: Muller, M, Paulik, S
• Format: Journal Article Conference Proceeding
• Language: English
• Published: Weinheim Wiley-VCH Verlag 01-05-2008; WILEY-VCH Verlag; WILEY‐VCH Verlag; Wiley
• Subjects: Adsorption; Applied sciences; ATR-FTIR; Deposition; Exact sciences and technology; Immersion; Multilayers; Nanostructure; Organic polymers; Physicochemistry of polymers; poly(acrylic acid); poly(ethyleneimine); polyelectrolyte multilayers; Polyetherimides; Properties and characterization; SFM; Structure, morphology and analysis; Thin films; Self-assembled layer; Polyelectrolyte; Self assembly; Branched polymer; Liquid solid adsorption; Acrylic acid polymer; Multiple layer; Nanostructure; Kinetics; Experimental study; Polyethylene imine
• ISBN: 9783527324385; 3527324380
• ISSN: 1022-1360; 1521-3900
• DOI: 10.1002/masy.200850509

The deposition and the nanostructure of polyelectrolyte multilayers (PEM) of branched poly(ethyleneimine)/poly(acrylic acid) (PEI/PAC) was studied in dependence of the adsorption time (tADS) of the individual steps. PEM were reproducibly deposited applying up to z = 20 adsorption steps at the fixed pH combination of 10/4 and polyelectrolyte concentration cPEL = 0.005 M in a flow cell using an automated valve system. in situ ATR-FTIR spectroscopy and SFM were used for quantitative determination of deposited amount and thickness, respectively. A linear relation between PEL band integrals and thickness of thin PEM films was found. Varying tADS from 0.5 to 5 min in each of the adsorption steps resulted in a steep rise of the deposited PEM amount. For tADS > 5 min the deposition did only marginally increase. Evidence for the release of outermost located PEI upon PAC immersion (even step) and of outermost PAC upon PEI immersion (odd step) was obtained. SFM images on consecutively deposited PEM-6 showed a slight increase in structure size and roughness for increasing tADS. These studies help to prepare polyelectrolyte based films with controlled thickness for the interaction with biofluids in the biomedical and food field.