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Coatings with inversely switching behavior [Elektronische Ressource] : new applications of core-shell hydrogel particles / von Horecha Marta

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186 pages
Coatings with Inversely Switching Behavior. New Applications of CoreShell Hydrogel Particles. D I S S E R T A T I O N zzuurr EErrllaanngguunngg ddeess aakkaaddeemmiisscchheenn GGrraaddeess zzuurr EErrllaanngguunngg ddeess aakkaaddeemmiisscchheenn GGrraaddeess Doctor rerum naturalium ((((DDDDrrrr.... rrrreeeerrrr.... nnnnaaaatttt....)))) vorgelegt der Fakultät Mathematik und Naturwissenschaften der Technischen Universität Dresden von HORECHA MARTA ggggeeeebbbboooorrrreeeennnn aaaammmm 00004444 AAAAuuuugggguuuusssstttt 1111999977776666 iiiinnnn LLLLvvvviiiivvvv,,,, UUUUkkkkrrrraaaaiiiinnnneeee Eingereicht am 22.07.2010 Die Dissertation wurde in der Zeit von Oktober 2006 bis Juli 2010 im Institut für Polymer Forschung, Dresden angefertigt 1. INTRODUCTION...................................................... 1 1.1 PROLOGUE AND MOTIVATION ........................................ 1 1.2 GOAL OF THE WORK: CREATION OF SURFACES WITH INVERSELY SWITCHABLE WETTING BEHAVIOUR ..................... 5 1.3 OUTLINE ....................................................................... 9 2. THEORETICAL BACKGROUND AND LITERATURE OVERVIEW ................................................................... 10 2.1 WETTING PHENOMENA ................................................ 10 2.2 SWITCHING OF SURFACE PROPERTIES BY MEANS OF RESPONSIVE SUBSTANCES AT INTERFACE ............................ 20 2.
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Coatings with Inversely Switching Behavior.
NewApplicationsof CoreShell Hydrogel Particles.
D I S S ERTATION
zur Erlangung des akademischen Grades
Doctor rerum naturalium
(Dr. rer. nat.)
vorgelegt
der Fakultät Mathematik und Naturwissenschaften
der Technischen Universität Dresden
von
HORECHAMARTA
geboren am 04 August 1976 in Lviv, Ukraine
Eingereicht am 22.07.2010
Die Dissertation wurde in der Zeit von Oktober 2006 bis Juli 2010 im Institut für Polymer Forschung, Dresden angefertigt
1.3
1.2
1.
4.1
4.2
4.
SHELL................................................................................ 65
3.5
1.1
OF SURFACE WETTABILITY.................................................. 25
RESPONSIVE SUBSTANCES AT INTERFACE............................ 20
3.2
3.3
3.
3.1
CONCEPTS TO OBTAIN AN INVERSE SWITCHING EFFECT
OTHER METHODS......................................................... 53
EVALUATION OF PARAMETERS OF INVERSE SWITCHING. 54
2.2
2.3
2.1
EXPERIMENTAL TECHNIQUES.............................. 37
SCANNINGELECTRONMICROSCOPY............................ 43
DYNAMICLIGHTSCATTERING...................................... 46
ATOMICFORCEMICROSCOPY....................................... 37
MODIFICATION.................................................................... 29
SYNTHETIC APPROACHES TO OBTAIN THE CORESHELL
WETTING PHENOMENA................................................ 10
2.4
3.4
OVERVIEW................................................................... 10
THEORETICAL
OUTLINE....................................................................... 9
PROLOGUE ANDMOTIVATION........................................ 1
DROPSHAPEANALYSISTECHNIQUE(DSA) ................. 51
HYDROGELS AS ASMARTFOR SURFACE MATERIAL
2.
STRUCTURES HAVING HYDROGEL CORE AND HYDROPHOBIC
RESULTS AND DISCUSSIONS................................ 54
INTRODUCTION...................................................... 1
BACKGROUND AND LITERATURE
SWITCHING OF SURFACE PROPERTIES BY MEANS OF
INVERSELY SWITCHABLE WETTING BEHAVIOUR..................... 5
GOAL OF THE WORK:CREATION OF SURFACES WITH
4.2.1SUBSTRATE SELECTION AND CHARACTERIZATION.................684.2.2“ONEPOT SYNTHETIC ROUTE TO CORESHELL PARTICLES VIA INVERSE SUSPENSION POLYMERIZATION..............................................704.2.2.1Synthesis and characterization of shellforming polymeric surfactant ............................................................................734.2.2.2Selection of the monomer for the formation of inner part of coreshell particles ...................................................................754.2.2.3Synthesis of coreshell particles via inverse suspension polymerization and their characterization ......................784.2.2.4“Contraphilic” surfaces prepared using coreshell particles synthesized by “onepot” approach.......................................834.2.3PREPARATION OF THE CORESHELL PARTICLES VIA BOTTOMUPAPPROACH............................................................................934.2.3.1Synthesis, characterization and tuning the composition of coreforming microgels with suitable swelling effect .95
4.2.3.2Formation of loose periodic arrays of microgels on the substrate ......................................................................................1024.2.3.3Surface density as a function of swelling effect .........1074.2.3.4Measurements of the maximal pressure developing upon the swelling of the microgels ....................................................1084.2.3.5Chemical modification of hydrogel microparticles.....1104.2.3.6.............................115Confined swelling of the microgels 4.2.3.7Adsorption of oppositely charged nanoparticles on the surface of microgels............................................................................1244.2.3.8Graftingfrom polymerization of shell on the microgels surface................................................................................1284.2.3.9Utilization of polyisoprene latex for PI shell formation ......................................................................................134
4.2.3.10Crosslinking of the shell ............................................142
4.2.4SWITCHING PROPERTIES OF HYDROPHILIC SURFACES COVERED WITH HYDROPHOBIC CORESHELL MICROGELS SWELLABLE IN WATER .......................................................................................... 1464.2.4.1Responsive surfaces fabricated via “bottomup” approach: insitu AFM monitoring of the waterinduced change of
the surface coverage........................................................................... 1465.SUMMARY.......................................................... 153
6.
REFERENCES..................................................... 159
PVA   poly(vinyl alcohol)
SEM  Scanning Electron Microscopy TGA  Thermogravimetric Analysis
temperature
PDI  polydispersity index PE  polyethylene
hydrochloride
SEC  Size Exclusion
tBA  tertbutylacrylate VA  vinylamine
BP  4hydrohybenzophenone
AIBN  azobis(isobutyronitril)
WCA  water contact angle
MAA  methacrylic acid
RMS  root mean square
NaHSS Nhydroxysulfosuccinimide
methacrylate)
TMP  trimethylpentane
MBA N,Nmethylenbisacrylamide
DSA  Drop Shape Analysis
EDC  1ethyl3[3dimethyl
LIST OFABBREVIATIONS
aminopropyl] carbodiimide
PAA  poly(acrylic acid)
PDEA  poly(2(diethylamino)ethyl
NIPAM Nisopropylacrylamide
SAM  selfassembled monolayer
DMF N,Ndimethylformamide
NMR  Nuclear Magnetic Resonance
HLB  hydrophiliclipophilic balance KPS  potassium persulfate
AA  acrylic acid
PS  polystyrene
PMMA  poly(methyl methacrylate)
PI  polyisoprene
PAAm  polyacrylamide
PBPA  poly(benzophenone acrylate)
PEG  poly(ethylene glycol)
Chromatography
AFM  Atomic Force Microscopy
AAm  acrylamide
AEMA  2aminoehyl methacrylate
GPC  Gel Permission
VPT  volume phase transition
SDS  sodium dodecylsulfate
P4VP  poly(4vinylpyridine)
Chromatography
NBA  4Nitrobenzaldehyde
BPA  4acryloyloxybenzophenone DAIB  (diacetoxy) iodobenzene DCC N,N'dicyclohexylcarbodiimid DLS  Dynamic Light Scattering DMAP  4(dimethylamino)pyridin
PEO  poly(ethylene oxide)
PNIPAM – poly(Nisopropylacrylamide)
PGMA  poly(glycidyl methacrylate)
PTFE  polytetrafluoroethylene
HEMA  2hydrohyethyl methacrylate
LCST  low critical solution
1.INTRODUCTION
1 Introduction and Motivation
1.1PROLOGUE ANDMOTIVATION
Surface wettability has been a topic of scientific investigation for
over 60 years. This great level of interest has been fueled by the
fundamental
importance
of
wetting
phenomena
in
various
technological applications, e.g. textile technology, production of water
[1] [2] repellant materials , spraying of paints and agricultural chemicals ,
penetration of ink in paper, impart to fabrics adsorbing and desorbing
[3] properties , etc. Hydrophobic and superhydrophobic materials are
widely used for many functions including the design and manufacture
[4] [5] of selfcleaning panes , waterproof textiles, microfluidic devices ,
hydroprotection
[6] protection ,
of
reinforced
biofouling
concrete
[7] protection ,
constructions,
prevention
of
corrosion
capillary
condensation and icing, shielding of surfaces against radioactive,
organic, and inorganic contaminations and many others.
With such a high degree of applications in modern technologies,
the materials used are themselves the subject of modification with the
purpose of controlling their surface properties. It is noteworthy to
mention that the cost of materials being modified is an extremely
important factor for the evaluation of their innovative potential.
Usually, high costs of raw materials are the main limiting factor,
which restrict manufacture of the final product with desired technical
properties. Fortunately, wettability is a surface feature, which is
mainly defined by the structure and properties of a few nanometers
thick superficial layer rather than by the characteristics of the bulk
material as a whole. Therefore, one of the most productive and cost
efficient methods for the creation of novel materials is to develop an
1
1 Introduction and Motivation
external coating on the surface of existing ones. substances with dissimilar properties are usually used as coatings in order to correct or
totally change the surface properties of the raw material.
As a practical aspect of a material usage is often defined by its physical and chemical surface properties, numerous tasks could not be realized without the use of surface modifications, coatings and thin
film technology. Coating techniques can be used to improve a material technical feature, look and performance. Routinely used examples of such materials applications include wearresistant coatings, which are
used on tools or machine parts, or thin films on paned glass which optimize the transmission or reflection of selected parts of the
electromagnetic spectrum. Many innovative products would not even
exist without the special properties provided by thin films. Prominent examples are computer hard disc drive, optical data storage media like CDs, DVDs and Blueray disks, flat displays and thinfilm solar cells.
Therefore, the need for efficient and effective methods of surface modification becomes increasingly important in allowing the production of far superior products in terms of altered mechanical
(wear, friction resistance,) chemical (corrosion protection, permeation control, enhanced biocompatibility, thermal insulation), electrical (improved conductivity) or optical (transmission, reflection, absorption,
colour adjustment) properties. Coatings can provide complex functionalities to surfaces, significantly changing their properties, compared to uncoated material. Many coating deposition techniques and surface treatments are
available for this purpose. If secondary material is added to the surface, the process is referred to as coating deposition process; however, if the surface microstructure and / or chemical composition
are altered, then the process is referred to as a surface modification process. Selection of the coating deposition or surface modification techniques depends on the functional requirements, shape, size and
2
adapt their structure by the rearrangement of interfacial components
[10] devices ,
textiles,
Since the wetting behaviour of material is strongly dependent on
colloidal
principle.
properties from hydrophilic to hydrophobic and vice versa, are of
energy. A number of switchable or adaptive coatings, which react to
considerable interest because of their potential applications including
valves.
In
tissue engineering and cell growth, creation of “intelligent” breath
Surfaces with switchable wetting behaviour, able to change their
3
[8] and surfaces is required for new concepts of sensors , drug delivery
and
selfregulating
particular, the design of a new generation of such “smart” materials
assembly
under the changing of environment in order to minimize surface
active
different stimuli from the environment, can be created using this
resistance, wear and scratch resistance, chemical stability of a raw
properties of the substrate,
and
dynamically active systems, usually achieved by a combination of
the surface structure and chemical composition, it is possible to
of
prepare the surface as a dynamic system that consists of two
coating
improve adhesion, wettability, corrosion
the
correct reflection or modify optical properties, etc.
materials, they can also provide conductive properties to a surface,
compatibility, adhesion, coating equipment and cost.
Functional coatings can
microfluidic
modern coatings quality have turned to an idea of creation of adaptive
material,
[11] techniques .
[9] systems ,
Recently, the process of development and the improvement of
materials with opposite properties, such sensitive surfaces are able to
or sensitive (also called “smart” or “intelligent”) surfaces. Based on
waterrepelling
nature
Coatings applied by deposition techniques are basically of two
1 Introduction and Motivation
in the automotive, home appliances, hardware, costume, jewellery etc.
types  decorative and functional. Decorative coatings are widely used
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