Detailed structure of molecularly thin polyelectrolyte multilayer films on solid substrates as revealed by neutron reflectometry

Macromolecules

Volumn 31, Issue 25, 1998, Pages 8893-8906

  Lösche, Mathias ^a   Schmitt, Johannes ^b   Decher, Gero ^b,c   Bouwman, Wim G ^d,e   Kjaer, Kristian ^d  

^a UNIVERSITY OF LEIPZIG   (Germany)

^b INSTITUT CHARLES SADRON   (France)

^c UNIVERSITÉ DE STRASBOURG   (France)

^d TECHNICAL UNIVERSITY OF DENMARK   (Denmark)

^e DELFT UNIVERSITY OF TECHNOLOGY   (Netherlands)

Author keywords

[No Author keywords available]

Indexed keywords

ADSORPTION; DEPOSITION; MOLECULAR STRUCTURE; MULTILAYERS; POLYELECTROLYTES; POLYMERIZATION; SUBSTRATES; SURFACE ROUGHNESS; THIN FILMS;

NEUTRON REFLECTOMETRY; SELF-ASSEMBLED POLYELECTROLYTE FILMS;

PLASTIC FILMS;

EID: 0032292495     PISSN: 00249297     EISSN: None     Source Type: Journal    
DOI: 10.1021/ma980910p     Document Type: Article

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19. -1, is in agreement with experimental observations.
20. w = 530-700.
21. -1, above.
22. To explain the unusual structure of the reflectograms shown in Figures 3 and 4, we also tested several defect models to find out whether a particular type of defect increases the quality of the model fit significantly. These tests included models in which the structures were laterally inhomogeneous, i.e., it was assumed that two slightly different r.u.'s lead to incoherent summation of different reflectivities. In other attempts it was assumed that the r.u.'s had one particular thickness near to the substrate and a different one further away, after the deposition of k layers, or that the thickness of one particular r.u., at a position k′, was different from that of all other r.u.'s. Although all these defect structures afforded slightly better fits than the original model in which all r.u.'s were assumed equivalent, these improvements were only due to the higher number of adjustable parameters which all defect models necessarily infer.
23. 26
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