Amorphous, multi phase polymer network systems with shape memory properties by photopolymerization [Elektronische Ressource] / vorgelegt von Nok-young Choi

Sujets

• Physik
• Astronomie

Informations

• Publié par: rheinisch-westfalischen_technischen_hochschule_-rwth-_aachen
• Publié le: 01 janvier 2002
• Nombre de lectures: 21
• Langue: Deutsch
• Poids de l'ouvrage: 1 Mo

Extrait

Amorphous, Multi-phase Polymer Network
Systems with Shape-Memory Properties
by Photopolymerization
Nok-young ChoiAmorphous, Multi-phase Polymer Network
Systems with Shape-Memory Properties
by Photopolymerization
Von der Fakultät für Mathematik, Informatik und Naturwissenschaften
der Rheinisch-Westfälischen Technischen Hochschule Aachen
zur Erlangung des akademischen Grades einer
Doktorin der Naturwissenschaften genehmigte Dissertation
vorgelegt von
Diplom-Chemikerin
Nok-young Choi
aus Tae-gu, Südkorea
Berichter: Universitätsprofessor Dr. rer. nat. H. Höcker
Universitätsprofessor Dr. rer. nat. B. Blümich
Tag der mündlichen Prüfung: 6. September, 2002
Diese Dissertation ist auf den Internetseiten der Hochschulbibliothek online verfügbar.Meinen Eltern
in Dankbarkeit gewidmet
Die vorliegende Arbeit wurde unter Leitung von Herrn Prof. Dr. rer. nat. Hartwig
Höcker am Lehrstuhl für Textilchemie und Makromolekulare Chemie der Rheinisch-
Westfälisch-Technischen Hochschule Aachen in der Zeit von März 1999 bis Juni
2002 durchgeführt.Contents I
Contents
Abbreviations and symbols ......................................................................................IV
Nomenclature..............................................................................................................V
1 Introduction............................................................................................................. 1
1.1 Amorphous polymers and glass transition ......................................................... 1
1.1.1 Determination methods of glass transition........................................................................ 3
1.1.2 Amorphous polymers in industry....................................................................................... 6
1.2 Shape-memory polymers with amorphous switching segments......................... 7
1.2.1 Thermoplastic elastomers............................................................................................... 10
1.2.2 Covalently crosslinked polymers .................................................................................... 11
1.2.3 Others ............................................................................................................................. 11
1.3 Degradable implant materials........................................................................... 12
1.3.1 Polymers from dilactides and diglycolide........................................................................ 13
1.3.2 Degradable shape-memory polymers for potential biomedical application.................... 16
2 Aims....................................................................................................................... 18
3 Concept ................................................................................................................. 18
4 Networks of oligo[(L-lactide)-ran-glycolide]dimethacrylates............................ 22
4.1 Polymerization kinetics and characterization of network precursors ................ 22
4.2 Network preparation and characterization........................................................ 31
4.3 Solid-state NMR characterization of the networks............................................ 42
4.4 Analysis of shape-memory properties.............................................................. 48
4.5 Comparison of thermal transitions determined with different methods............. 61
5 AB-Networks of oligo[(L-lactide)-ran-glycolide]dimethacrylates and various
acrylates ................................................................................................................ 62
5.1 Networks of oligo[(L-lactide)-ran-glycolide]dimethacrylates and ethylacrylate 65
5.2 Networks of oligo[(L-lactide)-ran-glycolide]dimethacrylates and butylacrylate 69
5.3 Networks of oligo[(L-lactide)-ran-glycolide]dimethacrylates and hexylacrylate 75
5.4 Comparison of phase-separation and glass transition of AB-networks ............ 81
6 Networks of oligo[(L-lactide)-ran-glycolide]dimethacrylate
and polyether dimethacrylates ............................................................................ 85
6.1 Approach with poly(ethylene glycol)dimethacrylates -
Influence of molecular weight on phase-separation ......................................... 85
6.2 Approach with Poly(propylene glycol)dimethacrylates -
Influence of molecular weight on phase-separation 87ContentsII
6.3 Compatibilization with diblockcopolymers ....................................................... 90
7 Networks of ABA triblockcopolymers................................................................. 92
7.1 Approach with poly[(L-lactide)-ran-glycolide]-b-poly(ethylene oxide)-b-
poly[(L-lactide)-ran-glycolide]dimethacrylates ................................................. 92
7.2 Approach with poly[(L-lactide)-ran-glycolide]-b-poly(propylene oxide)-
b-poly[(L-lactide)-ran-glycolide]dimethacrylates .............................................. 94
7.3 Networks of poly(rac-lactide)-b-poly(propylene oxide)-b-
poly(rac-lactide)dimethacrylates...................................................................... 96
7.3.1 Synthesis and characterization of network precursors and network
– Influence of block length on the phase-separation ..................................................... 98
7.3.2 Shape-memory properties of networks......................................................................... 106
7.3.3 Hydrolytical degradation of networks............................................................................ 109
8 Networks of diblockcopolymer poly(propylene oxide)-b-poly(rac-lactide) ... 120
9 Summary ............................................................................................................. 126
10 Experimental Part .............................................................................................. 130
10.1 Materials...................................................................................................... 130
10.2 Syntheses.................................................................................................... 131
10.2.1 Ring-opening polymerizations ................................................................................... 131
10.2.2 Trifluoroacetylation of macrodiols .............................................................................. 133
10.2.3 Methacrylations of macrodiols and macromonools ................................................... 133
10.2.4 UV-curing of network precursors ............................................................................... 134
10.2.5 Syntheses related to the conversion of methylmethacrylate to methacryloylchloride136
10.2.6 Synthesis of linear and crosslinked polyethyl-, polybutyl-, and polyhexylacrylate..... 136
10.3 Experimental methods................................................................................. 137
10.3.1 Nuclear magnetic resonance (NMR) ......................................................................... 137
10.3.2 Multidetector gel permeation chromatography (GPC)............................................... 139
10.3.3 Vapor pressure osmometry (VPO) ........................................................................... 139
10.3.4 Differential scanning calorimetry (DSC)..................................................................... 139
10.3.5 Infrared (IR) spectroscopy ......................................................................................... 139
10.3.6 Film preparation for subsequent photocuring ............................................................ 140
10.3.7 Determination of gel content, degree of swelling, and density of networks............... 140
10.3.8 Dynamic mechanical thermal analysis (DMTA)......................................................... 141
10.3.9 Tensile tests............................................................................................................... 141
10.3.10 Cyclic thermomechanical experiments ...................................................................... 141
10.3.11 Transmission electron microscope (TEM) ................................................................. 143
10.3.12 Inductively coupled plasma atomic emission spectrometry (ICP-AES)..................... 143
10.3.13 Solid phase microextraction - gas chromatography/ mass spectroscopy
(SPME- GC/MS) 143Contents III
10.3.14 Hydrolytical degradation experiment ......................................................................... 143
11 Literature ............................................................................................................ 144
12 Appendix 149
12.1 Preparation of a network of poly(rac-lactide)-b-poly(propylene oxide)-b-
poly(rac-lactide) dimethacrylates for biocompatibility tests.......................... 149
12.2 NMR Spectra analysis of initiators, monomers, and model compounds... 149
1
12.3 H-NMR spectra analysis of network precursors and compatiblilizer......... 155
1312.4 C-NMR, Xe network spectra and photo series.......................................... 167Abbreviations and symbolsIV
Abbreviations and symbols
3
J vicinal coupling constant
AIBN α,α‘-azo-isobutyronitrile
Bu butyl
CP cross polarization
d density
D degree of methacrylationa
D