Effects of synthesis conditions on the nanostructre of CexZr1-xO2 mesoporous ceramics.

CexZr1-xO2 (0.5 ≤ x ≤ 0.9) were synthesized with Zr and Ce chloride precursors, using the triblock copolymer Pluronic P123 and HCl (2 mol/L). The pH adjustment was performed in two ways: synthesis A used 11.4 mL of a NH4OH solution added at once to the initial mixture, composed by metal precursors and template in HCl; synthesis B was done by dripping slowly until the change of pH value (between 3 and 6). In this work, CexZr1-xO2 samples synthesized by these two processes are compared. The effects of pH values in materials characteristics were also evaluated. These samples were analysed by X-Ray Diffraction (XRD) with Rietveld refinement, and Nitrogen Adsorption/Desorption. In both processes, the studied materials presented two crystalline phases of CexZr1-xO2 solid solution: cubic and tetragonal. The synthesis A also presented a tetragonal phase of ZrO2. The average crystallite size and the Brunauer- Emmett-Teller (BET) surface area are bigger in process A. Both processes give samples with a mesoporous structure.

An alternative blocking layer for titanium dioxide (TiO 2) solar cell applications

In hybrid organic solar cells a blocking layer between transparent electrode and nanocrystalline titania particles is essential to prevent short-circuiting and current loss through recombination at the electrode interface. Here the preparation of a uniform hybrid blocking layer which is composed of conducting titania nanoparticles embedded in an insulating polymer derived ceramic is presented. This blocking layer is prepared by sol-gel chemistry where an amphiphilic block copolymer is used as a templating agent. A novel poly(dimethylsiloxane) containing amphiphilic block copolymer poly(ethyleneglycol)methylethermethacrylate-block-poly(dimethylsiloxane)-block-poly(ethyleneglycol)methylethermethacrylate has been synthesized to act as the templating agent. Plasma treatment uncovered titania surface from any polymer. Annealing at 450°C under nitrogen resulted in anatase titania with polymer derived silicon oxycarbide ceramic. Electrical characterization by conductive scanning probe microscopy experiments revealed a percolating titania network separated by an insulating ceramic matrix. Scanning Kelvin probe force microscopy showed predominant presence of titania particles on the surface creating a large surface area for dye absorption. The uniformity of the percolating structures was proven by microbeam grazing incidence small angle x-ray scattering. First applications in hybrid organic solar cells in comparison with conventional titanium dioxide blocking layer containing devices revealed 15 fold increases in corresponding efficiencies. Poly(dimethylsiloxane)-block-poly(ethyleneglycol)methylethermethacrylate and poly(ethyleneoxide)-poly(dimethylsiloxane)methylmethacrylate diblock copolymers were also synthesized. Their titania nanocomposite films were compared with the integrated blocking layer. Liner poly(ethyleneoxide) containing diblock copolymer resulted in highly ordered foam like structures. The effect of heating temperature rise to 600°C and 1000°C on titania morphology was investigated by scanning electron and force microscopy and x-ray scattering. Sol-gel contents, hydrochloric acid, titania precursor and amphiphilic triblock copolymer were altered to see their effect on titania morphology. Increase in block copolymer content resulted in titania particles of diameter 15-20 nm.

Synthetic routes toward functional block copolymers and bioconjugates via RAFT polymerization

Synthetic Routes toward Functional Block Copolymers and Bioconjugates via RAFT PolymerizationrnSynthesewege für funktionelle Blockcopolymere und Biohybride über RAFT PolymerisationrnDissertation von Dipl.-Chem. Kerstin T. WissrnIm Rahmen dieser Arbeit wurden effiziente Methoden für die Funktionalisierung beider Polymerkettenenden für Polymer- und Bioanbindung von Polymeren entwickelt, die mittels „Reversible Addition-Fragmentation Chain Transfer“ (RAFT) Polymerisation hergestellt wurden. Zu diesem Zweck wurde ein Dithioester-basiertes Kettentransferagens (CTA) mit einer Aktivestereinheit in der R-Gruppe (Pentafluorphenyl-4-phenylthiocarbonylthio-4-cyanovaleriansäureester, kurz PFP-CTA) synthetisiert und seine Anwendung als universelles Werkzeug für die Funktionalisierung der -Endgruppe demonstriert. Zum Einen wurde gezeigt, wie dieser PFP-CTA als Vorläufer für die Synthese anderer funktioneller CTAs durch einfache Aminolyse des Aktivesters genutzt werden kann und somit den synthetischen Aufwand, der üblicherweise mit der Entwicklung neuer CTAs verbunden ist, reduzieren kann. Zum Anderen konnte der PFP-CTA für die Synthese verschiedener Poly(methacrylate) mit enger Molekulargewichtsverteilung und wohl definierter reaktiver -Endgruppe verwendet werden. Dieses Kettenende konnte dann erfolgreich mit verschiedenen primären Aminen wie Propargylamin, 1-Azido-3-aminopropan und Ethylendiamin oder direkt mit den Amin-Endgruppen verschiedener Peptide umgesetzt werden.rnAus der Reaktion des PFP-CTAs mit Propargylamin wurde ein Alkin-CTA erhalten, der sich als effizientes Werkzeug für die RAFT Polymerisation verschiedener Methacrylate erwiesen hat. Der Einbau der Alkin-Funktion am -Kettenende wurde mittels 1H und 13C NMR Spektroskopie sowie MALDI TOF Massenspektroskopie bestätigt. Als Modelreaktion wurde die Kopplung eines solchen alkin-terminierten Poly(di(ethylenglykol)methylethermethacrylates) (PDEGMEMA) mit azid-terminiertem Poly(tert-butylmethacrylat), das mittels Umsetzung einer Aktivester-Endgruppe erhalten wurde, als kupferkatalysierte Azid-Alkin-Cycloaddition (CuAAC) durchgeführt. Die Aufarbeitung des resultierenden Diblockcopolymers durch Fällen ermöglichte die vollständige Abtrennung des Polymerblocks 1, der im Überschuss eingesetzt wurde. Darüber hinaus blieb nur ein sehr kleiner Anteil (< 2 Gew.-%) nicht umgesetzten Polymerblocks 2, was eine erfolgreiche Polymeranbindung und die Effizienz der Endgruppen-Funktionalisierung ausgehend von der Aktivester--Endgruppe belegt.rnDie direkte Reaktion von stimuli-responsiven Polymeren mit Pentafluorphenyl(PFP)ester-Endgruppen, namentlich PDEGMEMA und Poly(oligo(ethylenglykol)methylethermethacrylat), mit kollagen-ähnlichen Peptiden ergab wohl definierte Polymer-Peptid-Diblockcopolymere und Polymer-Peptid-Polymer-Triblockcopolymer unter nahezu quantitativer Umsetzung der Endgruppen. Alle Produkte konnten vollständig von nicht umgesetztem Überschuss des Homopolymers befreit werden. In Analogie zu natürlichem Kollagen und dem nicht funktionalisierten kollagen-ähnlichen Peptid bilden die PDEGMEMA-basierten, entschützten Hybridcopolymere Trimere mit kollagen-ähnlichen Triple-Helices in kalter wässriger Lösung, was mittels Zirkular-Dichroismus-Spektroskopie (CD) nachgewiesen werden konnte. Temperaturabhängige CD-Spektroskopie, Trübungsmessungen und dynamische Lichtstreuung deuteten darauf hin, dass sie bei höheren Temperaturen doppelt stimuli-responsive Überstrukturen bilden, die mindestens zwei konformative Übergänge beim Aufheizen durchlaufen. Einer dieser Übergänge wird durch den hydrophoben Kollaps des Polymerblocks induziert, der andere durch Entfalten der kollagen-ähnlichen Triple-Helices.rnAls Ausweitung dieser synthetischen Strategie wurde homotelecheles PDEGMEMA mit zwei PFP-Esterendgruppen dargestellt, wozu der PFP-CTA für die Funktionalisierung der -Endgruppe und die radikalische Substitution des Dithioesters durch Behandlung mit einem Überschuss eines funktionellen AIBN-Derivates für die Funktionalisierung der -Endgruppe ausgenutzt wurde. Die Umsetzung der beiden reaktiven Kettenenden mit dem N-Terminus eines Peptidblocks ergab ein Peptid-Polymer-Peptid Triblockcopolymer.rnSchließlich konnten die anorganisch-organischen Hybridmaterialien PMSSQ-Poly(2,2-diethoxyethylacrylat) (PMSSQ-PDEEA) und PMSSQ-Poly(1,3-dioxolan-2-ylmethylacrylat) (PMSSQ-PDMA) für die Herstellung robuster, peptid-reaktiver Oberflächen durch Spin Coaten und thermisch induziertes Vernetzen angewendet werden. Nach saurem Entschützen der Acetalgruppen in diesen Filmen konnten die resultierenden Aldehydgruppen durch einfaches Eintauchen in eine Lösung mit einer Auswahl von Aminen und Hydroxylaminen umgesetzt werden, wodurch die Oberflächenhydrophilie modifiziert werden konnte. Darüber hinaus konnten auf Basis der unterschiedlichen Stabilität der zwei hier verglichenen Acetalgruppen Entschützungsprotokolle für die exklusive Entschützung der Diethylacetale in PMSSQ-PDEEA und deren Umsetzung ohne Entschützung der zyklischen Ethylenacetale in PMSSQ-PDMA entwickelt werden, die die Herstellung multifunktioneller Oberflächenbeschichtungen z.B. für die Proteinimmobilisierung ermöglichen.

Synthesis of high surface area TiO2 nanoparticles by mild acid treatment with HCl or HI for photocatalytic propene oxidation

Nanostructured TiO2 photocatalysts with small crystalline sizes have been synthesized by sol-gel using the amphiphilic triblock copolymer Pluronic P123 as template. A new synthesis route, based on the treatment of TiO2 xerogels with acid-ethanol mixtures in two different steps, synthesis and extraction-crystallization, has been investigated, analyzing two acids, hydrochloric and hydriodic acid. As reference, samples have also been prepared by extraction-crystallization in ethanol, being these TiO2 materials amorphous and presenting higher porosities. The prepared materials present different degrees of crystallinity depending on the experimental conditions used. In general, these materials exhibit high surface areas, with an important contribution of microporosity and mesoporosity, and with very small size anatase crystals, ranging from 5 to 7 nm. The activity of the obtained photocatalysts has been assessed in the oxidation of propene in gas phase at low concentration (100 ppmv) under a UVA lamp with 365 nm wavelength. In the conditions studied, these photocatalysts show different activities in the oxidation of propene which do not depend on their surface areas, but on their crystallinity and band gap energies, being sample prepared with HCl both during synthesis and in extraction-crystallizations steps, the most active one, with superior performance than Evonik P25.

Comparative Analysis of Structural and Morphological Properties of Large-Pore Periodic Mesoporous Organosilicas and Pure Silicas

A systematic study on the structural properties and external morphologies of large-pore mesoporous organosilicas synthesized using triblock copolymer EO20PO70EO20 as a template under low-acid conditions was carried out. By employing the characterization techniques of SAXS, FE-SEM, and physical adsorption of N-2 in combination with alpha(s)-plot method, the structural properties and external morphologies of large-pore mesoporous organosilicas were critically examined and compared with that of their pure-silica counterparts synthesized under similar conditions. It has been observed that unlike mesoporous pure silicas, the structural and morphological properties of mesoporous organosilicas are highly acid-sensitive. High-quality mesoporous organosilicas can only be obtained from synthesis gels with the molar ratios of HCl/H2O between 7.08 x 10(-4) and 6.33 x 10(-3), whereas mesoporous pure silicas with well-ordered structure can be obtained in a wider range of acid concentration. Simply by adjusting the HCl/H2O molar ratios, the micro-, meso-, and macroporosities of the organosilica materials can be finely tuned without obvious effect on their structural order. Such a behavior is closely related to their acid-controlled morphological evolution: from necklacelike fibers to cobweb-supported pearl-like particles and to nanosized particulates.

Control of ordered structure and morphology of large-pore periodic mesoporous organosilicas by inorganic salt

Highly ordered rodlike periodic mesoporous organosilicas (PMO) were successfully synthesized using 1.2-bis(trimethoxysilyl)ethane as an precursor and triblock copolymer P123 as a template at low acid concentration and in the presence of inorganic salts (KCl). The role of acid and salt as well as the effects of synthesis temperature and reactant mole ratio in the control of morphology and the formation of ordered mesostructure was systematically examined. It was found that the addition of inorganic salt can dramatically expand the range of the synthesis parameters to produce highly ordered PMO structure and improve the quality of PMO materials. The morphology of PMOs was significantly dependent on the induction time for precipitation. The uniform PMO rods can only be synthesized in a narrow range of acid and salt concentrations. The results also show that the optimized salt concentration (I M) and low acidity (0.167 M) were beneficial to the formation of not only highly ordered mesostructure but also rodlike morphology. Increasing acidity resulted in fast hydrolysis reaction and short rod or plate-like particles. Highly ordered rod can also be prepared at low temperature (35 degrees C) with high salt amount (1.5 M) or high temperature (45 degrees C) with low salt amount (0.5 M). Optimum reactant molar composition at 40 degrees C is 0.035P123:8KCl:1.34HCI:444H(2)O:1.0bis(trimethoxysilyl)ethane. Lower or higher SiO2/PI23 ratio led to the formation of uniform meso-macropores or pore-blocking effect. (c) 2005 Elsevier Inc. All rights reserved.

Controlled synthesis of poly(neopentyl p-styrene sulfonate) via reversible addition-fragmentation chain transfer polymerisation

The controlled synthesis of poly(neopentyl p-styrene sulfonate) (PNSS) using RAFT polymerisation has been studied. Selected experimental conditions led to the production of PNSS with variable molecular weights and low dispersities (D{stroke}≤1.50). The controlled synthesis of poly(neopentyl p-styrene sulfonate) (PNSS) using reversible addition-fragmentation chain transfer polymerisation has been studied under a wide range of experimental conditions. PNSS can be used as an organic-soluble, thermally labile precursor for industrially valuable poly(p-styrene sulfonate), widely employed in technologies such as ionic exchange membranes and organic electronics. The suitability of two different chain transfer agents, three solvents, three different monomer concentrations and two different temperatures for the polymerisation of neopentyl p-styrene sulfonate is discussed in terms of the kinetics of the process and characteristics of the final polymer. Production of PNSS with systematically variable molecular weights and low dispersities (D{stroke} ≤1.50 in all cases) has been achieved using 2-azidoethyl 2-(dodecylthiocarbonothioylthio)-2-methylpropionate in anisole at 75°C, with an initial monomer concentration of 4.0molL-1. Finally, a poly(neopentyl p-styrene sulfonate)-b-polybutadiene-b-poly(neopentyl p-styrene sulfonate) (PNSS-b-PBD-b-PNSS) triblock copolymer has been synthesised via azide-alkyne click chemistry. Moreover, subsequent thermolysis of the PNSS moieties generated poly(p-styrene sulfonate) end blocks. This strategy allows the fabrication of amphiphilic copolymer films from single organic solvents without the need for post-deposition chemical treatment.

Self-assembly-driven electrospinning:the transition from fibers to intact beaded morphologies

Polymer beads have attracted considerable interest for use in catalysis, drug delivery, and photo­nics due to their particular shape and surface morphology. Electrospinning, typically used for producing nanofibers, can also be used to fabricate polymer beads if the solution has a sufficiently low concentration. In this work, a novel approach for producing more uniform, intact beads is presented by electrospinning self-assembled block copolymer (BCP) solutions. This approach allows a relatively high polymer concentration to be used, yet with a low degree of entanglement between polymer chains due to microphase separation of the BCP in a selective solvent system. Herein, to demonstrate the technology, a well-studied polystyrene-poly(ethylene butylene)–polystyrene triblock copolymer is dissolved in a co-solvent system. The effect of solvent composition on the characteristics of the fibers and beads is intensively studied, and the mechanism of this fiber-to-bead is found to be dependent on microphase separation of the BCP.

Design and performance assessment of aortic heart valve for tissue engineering

Current artificial heart valves are classified as mechanical and bioprosthetic. An appealing pathway that promises to overcome the shortcomings of commercially available heart valves is offered by the interdisciplinary approach of cardiovascular tissue engineering. However, the mechanical properties of the Tissue Engineering Heart Valves (TEHV) are limited and generally fail in the long-term use. To meet this performance challenge novel biodegradable triblock copolymer poly(ethylene oxide)-polypropylene oxide)-poly(ethylene oxide) (PEO-PPO-PEO or F108) crosslinked to Silk Fibroin (F108-SilkC) to be used as tri-leaflet heart valve material was investigated. ^ Synthesis of ten polymers with varying concentration and thickness (55 µm, 75 µm and 100 µm) was achieved via a covalent crosslinking scheme using bifunctional polyethylene glycol diglycidyl ether (PEGDE). Static and fatigue testing were used to assess mechanical properties of films, and hydrodynamic testing was performed to determine performance under a simulated left ventricular flow regime. The crosslinked copolymer (F108-Silk C) showed greater flexibility and resilience, but inferior ultimate tensile strength, by increasing concentration of PEGDE. Concentration molar ratio of 80:1 (F108: Silk) and thickness of 75 µm showed longer fatigue life for both tension-tension and bending fatigue tests. Four valves out of twelve designed satisfactorily complied with minimum performance requirement ISO 5840, 2005. ^ In conclusion, it was demonstrated that the applicability of a degradable polymer in conjugation with silk fibroin for tissue engineering cardiovascular use, specifically for aortic valve leaflet design, met the performance demands. Thinner thicknesses (t<75 µm) in conjunction with stiffness lower than 320 MPa (80:1, F108: Silk) are essential for the correct functionality of proposed heart valve biomaterial F108-SilkC. Fatigue tests were demonstrated to be a useful tool to characterize biomaterials that undergo cyclic loading. ^

BLOCK COPOLYMERS CONTAINING A LOW-SURFACE-ENERGY BLOCK AND THEIR APPLICATIONS

This thesis reports the synthesis and/or applications of three types of block copolymers that each bear a low-surface-energy block. First, poly(dimethylsiloxane)-block-poly(2-cinnamoyloxyethyl acrylate) (PDMS-b-PCEA) was synthesized and characterized. Cotton coating using a micellar solution of this block copolymer yielded superhydrophobic cotton fabrics. X-ray photoelectron spectroscopy (XPS) and surface property analyses indicated that the PDMS block topped the polymer coating. Photocuring the cotton swatches crosslinked the underlying PCEA layer and yielded permanent coatings. More interestingly, hydrophilically patterned superhydrophobic cotton fabrics were produced using photolithography that allowed the crosslinking of the coating around irradiated fibers but the removal, by solvent extraction, of the coating on fibers that were not irradiated. Since water-based ink only permeated the uncoated regions, such patterned fabric was further used to print ink patterns onto substrates such as fabrics, cardboard, paper, wood, and aluminum foil. Then, another PDMS-based diblock copolymer poly(dimethylsiloxane)-block-poly(glycidyl methacrylate) (PDMS-b-PGMA) was prepared. Different from PCEA that photocrosslinked around cotton fibers, PGMA reacted with hydroxyl groups on cotton fiber surfaces to get covalently attached. Further, different PGMA chains crosslinked with each other. PDMS-b-PGMA-coated cotton fabrics have been used for oil-water separations. In addition, polymeric nanoparticles were grafted onto cotton fiber surface before PDMS-b-PGMA was used to cover the surfaces of the grafted spheres and the residual surfaces of the cotton fibers. These two types of fabrics, coated by the block copolymer alone or by the polymer nanospheres and then the copolymer, were characterized by scanning electron microscope (SEM), Fourier transform infrared spectroscopy (FT-IR), and water repellency analyses. A comprehensive comparative study was made of their performances in oil-water separation. Finally, a fluorinated ABC triblock copolymer poly(acrylic acid)-block-poly(2-cinnamoyloxyethyl methacrylate)-block-poly(2-perfluorooctylethyl methacrylate) (PAA-b-PCEMA-b-PFOEMA) was used to iii encapsulate air nanobubbles. The produced air nanobubbles were thermodynamically stable in water and were some 100 times more stable than commercially available perfluorocarbon-filled microbubbles under ultrasound. These nanobubbles, due to their small sizes and thus ability to permeate the capillary networks of organs and to reach tumors, may expand the applications of microbubbles in diagnostic ultrasonography and find new applications in ultrasound-regulated drug delivery.

Engineered Vesicles for Perchlorate Degradation

This study demonstrates the use of engineered vesicles to reduce perchlorate. Specifically, cell-free extracts containing perchlorate reductase and chlorite dismutase enzymes were encapsulated in a triblock copolymer vesicle functionalized with the outer membrane porin OmpF. The porin allows for perchlorate transport into the vesicles, inside which the encapsulated enzymes transform perchlorate to chloride. Perchlorate reduction was quantified using a methyl viologen colorimetric technique. The vesicle solutions had perchlorate-reducing activities ranging from 35-45 units per liter. This work shows that vesicles can provide a mechanism to utilize environmentally-relevant biological enzymes. When incorporated into a vesicle, the enzymes could be used outside of environmental conditions where they would normally be expressed by natural bacteria.

A SAXS study of the structure of gels formed by mixtures of polyoxyalkylene triblock copolymers

Small-angle X-ray scattering was used to characterise aqueous micellar gels of triblock copolymers E137S18E137, E82S9E82, E76S5E76, E62P39E62, and of two mixtures: E137S18E137 and E62P39E62 (Mix 1) and ES2S9E82 and E62P39E62 (Mix 2), each 50/50 wt%. E = oxyethylene, CH2CH2O; S = oxyphenylethylene, OCH2CH(C6H5); and P = oxypropylene, OCH2CH(CH3)- Within the concentration and temperature ranges investigated (30-40 wt% copolymer, 20-80 degrees C), spherical micelles of copolymers E137S18E137, E82S9ES2 and E62P39E62 packed into bodycentred cubic (BCC) structures. Gels of E76S5E76 were stable only at high concentrations and low temperatures, and a 70 wt/o copolymer solution at T = 30 degrees C formed a hexagonal gel consistent with cylindrical micelles. It is likely that the mixed copolymers would form two distributions of micelles, and more complex structures were expected. However, gels of Mix 2 had well-ordered BCC structures, while the less ordered gels of Mix 1 were also best characterised as BCC. (c) 2006 Society of Chemical Industry.

Internal nanoparticle structure of temperature-responsive self-assembled PNIPAM-b-PEG-b-PNIPAM triblock copolymers in aqueous solutions: NMR, SANS and light scattering studies

In this study we report detailed information on the internal structure of PNIPAM-b-PEG-b-PNIPAM nanoparticles formed from self-assembly in aqueous solutions upon increase in temperature. NMR spectroscopy, light scattering and small-angle neutron scattering (SANS) were used to monitor different stages of nanoparticle formation as a function of temperature, providing insight into the fundamental processes involved. The presence of PEG in a copolymer structure significantly affects the formation of nanoparticles, making their transition to occur over a broader temperature range. The crucial parameter that controls the transition is the ratio of PEG/PNIPAM. For pure PNIPAM, the transition is sharp; the higher the PEG/PNIPAM ratio results in a broader transition. This behavior is explained by different mechanisms of PNIPAM block incorporation during nanoparticle formation at different PEG/PNIPAM ratios. Contrast variation experiments using SANS show that the structure of nanoparticles above cloud point temperatures for PNIPAM-b-PEG-b-PNIPAM copolymers is drastically different from the structure of PNIPAM mesoglobules. In contrast with pure PNIPAM mesoglobules, where solid-like particles and chain network with a mesh size of 1-3 nm are present; nanoparticles formed from PNIPAM-b-PEG-b-PNIPAM copolymers have non-uniform structure with “frozen” areas interconnected by single chains in Gaussian conformation. SANS data with deuterated “invisible” PEG blocks imply that PEG is uniformly distributed inside of a nanoparticle. It is kinetically flexible PEG blocks which affect the nanoparticle formation by prevention of PNIPAM microphase separation.

Investigation by Combined Solid-State NMR and SAXS Methods of the Morphology and Domain Size in Polystyrene-b-Polyethylene Oxide-b-Polystyrene Triblock Copolymers

The microphase structure of a series of polystyrene-b-polyethylene oxide-b-polystyrene (SEOS) triblock copolymers with different compositions and molecular weights has been studied by solid-state NMR, DSC, wide and small angle X-ray scattering (WAXS and SAXS). WAXS and DSC measurements were used to detect the presence of crystalline domains of polyethyleneoxide (PEO) blocks at room temperature as a function of the copolymer chemical composition. Furthermore, DSC experiments allowed the determination of the melting temperatures of the crystalline part of the PEO blocks. SAXS measurements, performed above and below the melting temperature of the PEO blocks, revealed the formation of periodic structures, but the absence or the weakness of high order reflections peaks did not allow a clear assessment of the morphological structure of the copolymers. This information was inferred by combining the results obtained by SAXS and (1)H NMR spin diffusion experiments, which also provided an estimation of the size of the dispersed phases of the nanostructured copolymers. (C) 2009 Wiley Periodicals, Inc. J Polym Sci Part B: Polym Phys 48:55-64,2010