Tuning polymeric latex functionality via the miniemulsion technique [Elektronische Ressource] / vorgelegt von Daniel Crespy

Crd271

Informations

• Publié par: universitat_ulm
• Publié le: 01 janvier 2006
• Nombre de lectures: 9
• Langue: English
• Poids de l'ouvrage: 7 Mo

Extrait

Tuning Polymeric Latex Functionality
via The Miniemulsion Technique














Dissertation
Zur Erlangung des Doktorgrades Dr. Rer. Nat.
der Falkutät für Naturwissenschaften
der Universität Ulm



vorgelegt von
Daniel Crespy
aus Rennes, Frankreich
Ulm, 2006
























































Amtierender Dekan: Prof. Dr. K.-D. Spindler

1. Gutachter: Prof. Dr. K. Landfester
2. rof. Dr. N. Hüsing
Tag der Promotion: 1 Dezember 2006

Universität Ulm, Fakultät für Naturwissenschaften, 2006
2
























3Table of contents

1. INTRODUCTION……………………………………………………………………...…7

2. THEORETICAL SECTION………………………….......………………………….…11

2.1. Heterophase polymerizations……………...…………………………………………...12
2.1.1. The different types of polymerization………………………………………………….12
2.1.1.1. Chain-growth polymerization……...………………………………………………...12
2.1.1.2. Step-growth polymerization……………………………………………………….....13
2.1.2. Polymerizations in dispersion………………………………………………………….13
2.1.3. The Ouzo effect and the solvent displacement technique…………………………...…16
2.1.4. The miniemulsion polymerization……………………………………………………..16
2.1.4.1. Principle of the miniemulsion polymerization technique………..…………………..16
2.1.4.2. Stability of the miniemulsion..…..………………………………………………...…18
2.2. The free-radical polymerization in miniemulsion………………………………….…19
2.2.1. Free-radical polymerization in direct miniemulsion…………………………………...19
2.2.2. Free-radical polymerization in inverse miniemulsion………………………………….19
2.2.3. Copolymerization in heterophase systems……………………………………………..20
2.3. Anionic miniemulsion polymerization………………………………………………...22
2.3.1. Anionic miniemulsion polymerizations……………..…………………………………22
2.3.2. Anionic heterophase polymerization of lactams……………………………………….23
2.4. Miniemulsion polycondensation and polyaddition…………………………………...23
2.4.1. Step-growth polymerizations in miniemulsion………………………………………...23
2.4.2. Interfacial polycondensation in miniemulsion………………………………………....24

3. RELEVANT METHODS FOR CHARACTERIZATION…………………………….26

3.1. Light Scattering…………………………………………………………………………27
3.2. Electron microscopy (TEM, SEM)…………………………………………………….28
3.2.1. The scanning electron microscope……………………………………………………..28
3.2.2. The transmission electron microscope…………………………………………………30


44. RESULTS AND DISCUSSION………………………………………………………….31
4.1. Free-radical polymerization in miniemulsion………………………………………...32
4.1.1. Free-radical polymerization in direct miniemulsion …………………………………..32
4.1.1.1. Free-radical polymerization in direct miniemulsion in the presence of a solvent in the
dispersed phase…………………………………………………………………………….…32
4.1.1.2. Free-radical polymerization in the presence of metal complexes in direct
miniemulsion…………………………………………………………………………….……38
4.1.1.3. Free-radical polymerization initiated by borohydrides in direct miniemulsion…...…46
4.1.1.4. Free-radical copolymerization with a surfactant in direct miniemulsion………….....50
4.1.2. Free-radical polymerization in inverse miniemulsion……………………………….....59
4.1.2.1. Miniemulsion polymerization at high temperature…………………………………..59
4.1.2.2. Synthesis of nanocapsules via inverse free-radical miniemulsion polymerization…..69
4.2. Anionic polymerization of lactams in miniemulsion and synthesis of polyamide
latexes……………………………………………………………………………………...…70
4.2.1. Anionic polymerization of ε-caprolactam……………………………………………...71
4.2.2. Synthesis of polyamide 6 nanoparticles and nanocapsules via two miniemulsion/
solvent displacement techniques………………………………………….…………………..79
4.3. Polycondensation in miniemulsion systems………………………………………...…89
4.3.1. Polyamide latexes in miniemulsion polycondensation………………………………...89
4.3.1.1. Tentative synthesis of polyamide latexes in direct miniemulsion at low
temperature…………………………………………………………………………………....89
4.3.1.2. Tentative synthesis of polyamide latexes at low temperature in an inverse system....90
4.3.1.3. Tentative synthesis of polyamide latexes at higher temperature…………………….91
4.3.2. Polyurea and polyurethane latexes in miniemulsion polycondensation……………….92

5. CONCLUSION AND PERSPECTIVES……………………………………………….117

6. EXPERIMENTAL PART………………………………………………………………122

6.1. Miniemulsion free-radical polymerization…………………………………………..123
6.1.1. Free-radical polymerization in direct miniemulsion………………………………….123
6.1.1.1. Free-radical polymerization in direct miniemulsion in the presence of a solvent in the
disperse phase…………………………………………………………………………….…123
56.1.1.2. Free-radical polymerization in the presence of metal complexes in direct
miniemulsion………………………………………………………………………………...123
6.1.1.3. Free-radical polymerization initiated by borohydrides in direct miniemulsion…….124
6.1.1.4. Free-radical copolymerization with a surfactant in direct miniemulsion…………...125
6.1.2. Free-radical polymerization in inverse miniemulsion………………………………...125
6.1.2.1. Miniemulsion polymerization at high temperature…………………………………125
6.1.2.2. Synthesis of capsules with hydrophilic liquid core via radical miniemulsion
polymerization………………………………………………………………………………126
6.2. Anionic polymerization of lactams in miniemulsion and synthesis of polyamide
latexes……………………………………………………………………………………….127
6.2.1. Anionic polymerization of ε-caprolactam…………………………………………….127
6.2.2. Synthesis of polyamide 6 nanoparticles and nanocapsules via two miniemulsion/
solvent displacement hybrid techniques………………...…………………………………..129
6.3. Polycondensation in miniemulsion…………………………………………………...130
6.3.1. Polyamide latexes in miniemulsion polycondensation……………………………….130
6.3.1.1. Tentative synthesis of stable polyamide latexes by direct miniemulsion
polycondensation at low temperature…………………………………………………….…131
6.3.1.2. Tentative synthesis of stable polyamide latexes by inverse miniemulsion perature ………………………………………………………131
6.3.1.3. Tentative synthesis of stable polyamide latexes by miniemulsion polycondensation at
higher temperature ………………………………………………………………………….132
6.3.2. Polyurea and polyurethane latexes in miniemulsion polycondensation……………...132

7. APPENDIX………………………………………………………………………………135

7.1. Methods………………………………………………………………………………...136
7.2. Abbreviations……………………………………………………………………….…140
7.3. Symbols……………………………………………………………………………...…142

ACKNOWLEDGEMENTS……………………………………………………………….143

REFERENCES……………………………………………………………………………..147

ZUSAMMENFASSUNG UND AUSBLICK………...……………………………………158
6




1. Introduction



There was no "before" the beginning of our universe, because once upon a time there was no
time.

John D. Barrow (1952 - / )
American professor in the department of Applied Mathematics & Theoretical Physics,
Cambridge University.





















7A lot of efforts, either in academic or industrial research, are focusing on the design of new
polymers with superior properties compared to the old ones, or the improvement of known
polymers or processes. Industrially, the first possibility involves strong investments to start
creating some niches, which eventually become new markets. The second possibility needs
less investment but serious profits are generated only through huge mass production.
Heterophase polymerization is well established in the plastics industry since it benefits of
interesting advantages such as the good heat exchange with the surrounding medium and the
decrease of the viscosity compared to the bulk process. In the brilliant review “90 Years of
Polymer Latexes and Heterophase Polymerization: More vital than ever” [Ant_2003], Tauer
and Antonietti deal with what they call “the most obvious candidates with blockbuster
character”. Among them, there are the “dispersions of engineering plastics”. In the different
dispersion polymerization techniques, the miniemulsion technique is the most promising one.
Indeed, the miniemulsion droplets realize the concept of exceptionally stable nanoreactors.
The miniemulsion is hence naturally inscribed in the growing field of the nanoscience but also
has the potential to provide suitable materials for drug-delivery systems. Active research
related to the miniemulsion technique is currently exponentially sustained [SCO_2005].
Despite the recent advances in the miniemulsion technique concerning miniemulsion of
inorganic particles and dyes, almost every document concerning miniemulsion still deals with