Stress - structure correlations in grafted polymer films [Elektronische Ressource] / Sebastian Cornelius Lenz

Lenz Sebastian

Sujets

• Physik

Informations

• Publié par: johannes_gutenberg-universitat_mainz
• Publié le: 01 janvier 2009
• Nombre de lectures: 21
• Langue: English
• Poids de l'ouvrage: 4 Mo

Extrait

Stress – structure correlations
in grafted polymer films


Dissertation

zur Erlangung des Grades
Doktor der Naturwissenschaften



am Fachbereich Chemie, Pharmazie und Geowissenschaften
der Johannes Gutenberg-Universität Mainz




Sebastian Cornelius Lenz
geboren in Erding
Mainz, November 2009
































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Abgabedatum: 15.11.2009
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Die vorliegende Arbeit wurde am Institut für Physikalische Chemie der
Johannes-Gutenberg Universität Mainz
und am Max-Planck-Institut für Polymerforschung in Mainz
in der Zeit von November 2006 bis November 2009 angefertigt.
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Für den gläubigen Menschen steht Gott am Anfang, für den Wissenschaftler
am Ende aller seiner Überlegungen.
Max Planck
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Meiner liebsten Anna und Ihrer roten Nase
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Contents
I INTRODUCTION 1
II FUNDAMENTALS AND METHODS 5
II.1 Stresses 5
II.1.1 Definition 5
II.1.2 Stresses and thermodynamics 6
II.1.3 Micromechanical cantilever bending phenomena 7
II.1.4 mechantilever coating procedures 8
II.1.5 Micromechanical cantilever sensor arrays 9
II.1.6 Detection methods 10
II.1.7 NIR imaging interferometry 12
II.2 X-ray and neutron experiments 17
II.2.1 X-ray reflectivity 17
II.2.2 X-ray and neutron reflectivity on polymer films 20
II.2.3 Roughness profiles 23
II.2.4 Correlated interfaces 26
II.2.5 Introduction to grazing incidence small angle x-ray scattering (GISAXS) 30
II.2.5.1 GISAXS geometry 32
II.2.5.2 The Distorted Wave Born Approximation 33
II.2.6 µ-x-ray reflectivity and µ-GISAXS on MC arrays at BW4 35
+II.2.7 Neutron reflectivity at N-REX (FRM II) 39
II.3 Thermodynamics of mixing 43
II.3.1 Free energy of mixing 43
II.3.2 Collapsed/stretched polymer brushes 45
II.3.2.1 Polymer brush: Definition and models 45
II.3.2.2 Collapse-stretching of polymer brushes in mixed solvents 48
II.3.3 Phase separating polymer blends 51
II.4 Miscellaneous experimental techniques 57
II.4.1 Contact angle experiments 57
II.4.2 Gel Permeation Chromatography 57
II.4.3 Differential Scanning Calorimetry 57
II.4.4 Environmental scanning probe microscopy (SPM) 58
II.4.5 White light confocal microscopy 58
II.4.6 X-ray reflectivity from lab x-ray sources 59
II.5 Substrate preparation 60
II.5.1 Substrate cleaning 60
II.5.2 Preparation of passivating Au films 60
II.6 Materials 61
III GLOBAL SCATTERING FUNCTIONS: A TOOL FOR
GISAXS ANALYSIS 63
III.1 Introduction 63
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III.2 Theory 65
III.2.1 Approximation of diffuse scattering by BA and intrinsic limits 65
III.2.2 Unified Exponential/Power-Law Fit model 68
III.2.3 Fractal objects 70
III.2.4 Weakly correlated systems 72
III.3 Comparison with Simulations 75
III.4 Experimental verification 79
III.4.1 Unified analysis from model systems 79
III.4.2 Unified analysis from novel TiO /(PEO)MA–PDMS–MA(PEO) films 82 2
III.5 Summary 84
IV THERMAL RESPONSE OF SURFACE GRAFTED TWO-
DIMENSIONAL PS/PVME BLEND FILMS 85
IV.1 PS/PVME bulk properties 85
IV.2 Thin film phase separation 88
IV.3 Preparation of grafted to polymer films 90
IV.3.1 Introduction to specific and unspecific grafting to routes 90
IV.3.2 Surface functionalization with UV-sensitive benzophenone linkers 91
IV.3.3 Functionalization with polymers 93
IV.4 Effect of grafting point densities 97
IV.4.1 Hypothesis 98
IV.4.2 SPM results 99
IV.4.3 µ-XR and µ-GISAXS results 100
IV.4.4 Surface stress results 106
IV.4.5 Summary 111
IV.4.6 Grafting densities in fully active BP films 112
V STRESS/STRUCTURE CORRELATION IN GRAFTED
FROM PMMA BRUSHES 119
V.1 Motivation 119
V.2 Grafting from prepared polymer brushes 121
V.2.1 Introduction to grafting from with atomic transfer radical polymerization
(ATRP) 121
V.2.2 PMMA brushes prepared with surface initiated ATRP 123
V.2.3 Simultaneous MC sensor array/wafer coating 125
V.3 Neutron reflectivity results 129
V.3.1 Experimental objective 129
V.3.2 Data treatment 130
V.3.3 Fast collapse/swelling process 132
V.3.4 Gradual collapse/swelling transition 135
V.3.5 Summary of neutron reflectivity results 142
V.4 Surface stress experiments 143
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V.4.1 Experimental approach 144
V.4.2 Stress propagation for the swelling of the collapsed brush of dry/swollen origin
145
V.4.3 Summary of surface stress results 147
VI SUMMARY AND OUTLOOK 148
VII APPENDIX 151
VII.1 Optical constants 151
VII.2 Dimensional and mechanic properties of Si MC sensors 152
VII.3 Input-files used for IsGISAXS simulations 152
VII.3.1 Simulation of GISAXS from Au film 152
VII.3.2 Simulation of GISAXS from TiO2 particles buried in a PMMA film matrix 154
VII.3.3 Automatic IGOR Pro script for MC bending data analysis 155
REFERENCES 159
PUBLICATIONS 175

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