Готові списки джерел за темами / Self-Assembly of block copolymers

Добірка наукової літератури з теми "Self-Assembly of block copolymers"

Автор: Grafiati
Опубліковано: 7 липня 2024
Оновлено: 7 липня 2024

Оформте джерело за APA, MLA, Chicago, Harvard та іншими стилями

Оберіть тип джерела:

Ознайомтеся зі списками актуальних статей, книг, дисертацій, тез та інших наукових джерел на тему "Self-Assembly of block copolymers".

Біля кожної праці в переліку літератури доступна кнопка «Додати до бібліографії». Скористайтеся нею – і ми автоматично оформимо бібліографічне посилання на обрану працю в потрібному вам стилі цитування: APA, MLA, «Гарвард», «Чикаго», «Ванкувер» тощо.

Також ви можете завантажити повний текст наукової публікації у форматі «.pdf» та прочитати онлайн анотацію до роботи, якщо відповідні параметри наявні в метаданих.

Зміст

  1. Статті в журналах
  2. Дисертації
  3. Книги
  4. Частини книг
  5. Тези доповідей конференцій
  6. Звіти організацій

Статті в журналах з теми "Self-Assembly of block copolymers":

1

Abetz, Volker. "Self-Assembly of Block Copolymers." Polymers 12, no. 4 (April 2, 2020): 794. http://dx.doi.org/10.3390/polym12040794.

Повний текст джерела
Стилі APA, Harvard, Vancouver, ISO та ін.
2

Kuperkar, Ketan, Dhruvi Patel, Leonard Ionut Atanase, and Pratap Bahadur. "Amphiphilic Block Copolymers: Their Structures, and Self-Assembly to Polymeric Micelles and Polymersomes as Drug Delivery Vehicles." Polymers 14, no. 21 (November 3, 2022): 4702. http://dx.doi.org/10.3390/polym14214702.

Повний текст джерела
Стилі APA, Harvard, Vancouver, ISO та ін.
Анотація:
Self-assembly of amphiphilic block copolymers display a multiplicity of nanoscale periodic patterns proposed as a dominant tool for the ‘bottom-up’ fabrication of nanomaterials with different levels of ordering. The present review article focuses on the recent updates to the self-association of amphiphilic block copolymers in aqueous media into varied core-shell morphologies. We briefly describe the block copolymers, their types, microdomain formation in bulk and micellization in selective solvents. We also discuss the characteristic features of block copolymers nanoaggregates viz., polymer micelles (PMs) and polymersomes. Amphiphilic block copolymers (with a variety of hydrophobic blocks and hydrophilic blocks; often polyethylene oxide) self-assemble in water to micelles/niosomes similar to conventional nonionic surfactants with high drug loading capacity. Double hydrophilic block copolymers (DHBCs) made of neutral block-neutral block or neutral block-charged block can transform one block to become hydrophobic under the influence of a stimulus (physical/chemical/biological), and thus induced amphiphilicity and display self-assembly are discussed. Different kinds of polymer micelles (viz. shell and core-cross-linked, core-shell-corona, schizophrenic, crew cut, Janus) are presented in detail. Updates on polymerization-induced self-assembly (PISA) and crystallization-driven self-assembly (CDSA) are also provided. Polyion complexes (PICs) and polyion complex micelles (PICMs) are discussed. Applications of these block copolymeric micelles and polymersomes as nanocarriers in drug delivery systems are described.
3

Yoon, Jongseung, Wonmok Lee, and Edwin L. Thomas. "Self-Assembly of Block Copolymers for Photonic-Bandgap Materials." MRS Bulletin 30, no. 10 (October 2005): 721–26. http://dx.doi.org/10.1557/mrs2005.270.

Повний текст джерела
Стилі APA, Harvard, Vancouver, ISO та ін.
Анотація:
AbstractSelf-assembled block copolymer systems with an appropriate molecular weight to produce a length scale that will interact with visible light are an alternative platform material for the fabrication of large-area, well-ordered photonic-bandgap structures at visible and near-IR frequencies.Over the past years, one-, two-, and three-dimensional photonic crystals have been demonstrated with various microdomain structures created through microphase separation of block copolymers. The size and shape of periodic microstructures of block copolymers can be readily tuned by molecular weight, relative composition of the copolymer, and blending with homopolymers or plasticizers.The versatility of photonic crystals based on block copolymers is further increased by incorporating inorganic nanoparticles or liquid-crystalline guest molecules (or using a liquid-crystalline block), or by selective etching of one of the microdomains and backfilling with high-refractive-index materials. This article presents an overview of photonic-bandgap materials enabled by self-assembled block copolymers and discusses the morphology and photonic properties of block-copolymer-based photonic crystals containing nanocomposite additives.We also provide a view of the direction of future research, especially toward novel photonic devices.
4

Ma, Shuhui, Yushuang Hou, Jinlin Hao, Cuncai Lin, Jiawei Zhao, and Xin Sui. "Well-Defined Nanostructures by Block Copolymers and Mass Transport Applications in Energy Conversion." Polymers 14, no. 21 (October 28, 2022): 4568. http://dx.doi.org/10.3390/polym14214568.

Повний текст джерела
Стилі APA, Harvard, Vancouver, ISO та ін.
Анотація:
With the speedy progress in the research of nanomaterials, self-assembly technology has captured the high-profile interest of researchers because of its simplicity and ease of spontaneous formation of a stable ordered aggregation system. The self-assembly of block copolymers can be precisely regulated at the nanoscale to overcome the physical limits of conventional processing techniques. This bottom-up assembly strategy is simple, easy to control, and associated with high density and high order, which is of great significance for mass transportation through membrane materials. In this review, to investigate the regulation of block copolymer self-assembly structures, we systematically explored the factors that affect the self-assembly nanostructure. After discussing the formation of nanostructures of diverse block copolymers, this review highlights block copolymer-based mass transport membranes, which play the role of “energy enhancers” in concentration cells, fuel cells, and rechargeable batteries. We firmly believe that the introduction of block copolymers can facilitate the novel energy conversion to an entirely new plateau, and the research can inform a new generation of block copolymers for more promotion and improvement in new energy applications.
5

Benmouna, A., R. Benmouna, M. R. Bockstaller, and I. F. Hakem. "Self-Organization Schemes towards Thermodynamic Stable Bulk Heterojunction Morphologies: A Perspective on Future Fabrication Strategies of Polymer Photovoltaic Architectures." Advances in Physical Chemistry 2013 (April 16, 2013): 1–8. http://dx.doi.org/10.1155/2013/948189.

Повний текст джерела
Стилі APA, Harvard, Vancouver, ISO та ін.
Анотація:
Research efforts to improve our understanding of electronic polymers are developing fast because of their promising advantages over silicon in photovoltaic solar cells. A major challenge in the development of polymer photovoltaic devices is the viable fabrication strategies of stable bulk heterojunction architecture that will retain functionality during the expected lifetime of the device. Block copolymer self-assembly strategies have attracted particular attention as a scalable means toward thermodynamically stable microstructures that combine the ideal geometrical characteristics of a bulk heterojunction with the fortuitous combination of properties of the constituent blocks. Two primary routes that have been proposed in the literature involve the coassembly of block copolymers in which one domain is a hole conductor with the electron-conducting filler (such as fullerene derivatives) or the self-assembly of block copolymers in which the respective blocks function as hole and electron conductor. Either way has proven difficult because of the combination of synthetic challenges as well as the missing understanding of the complex governing parameters that control structure formation in semiconducting block copolymer blends. This paper summarizes important findings relating to structure formation of block copolymer and block copolymer/nanoparticle blend assembly that should provide a foundation for the future design of block copolymer-based photovoltaic systems.
6

Xie, Yihui, Nicolas Moreno, Victor M. Calo, Hong Cheng, Pei-Ying Hong, Rachid Sougrat, Ali R. Behzad, Russell Tayouo, and Suzana P. Nunes. "Synthesis of highly porous poly(tert-butyl acrylate)-b-polysulfone-b-poly(tert-butyl acrylate) asymmetric membranes." Polymer Chemistry 7, no. 18 (2016): 3076–89. http://dx.doi.org/10.1039/c6py00215c.

Повний текст джерела
Стилі APA, Harvard, Vancouver, ISO та ін.
Анотація:
For the first time, self-assembly and non-solvent induced phase separation was applied to polysulfone-based linear block copolymers, reaching mechanical stability much higher than other block copolymer membranes used in this method, which were mainly based on polystyrene blocks.
7

Wang, Zihao, Susu Tao, Yanyan Chu, Xiaoyan Xu, and Qinggang Tan. "Diameter of Carbon Nanotube-Directed Self-Assembly of Amphiphilic Block Copolymers." Materials 12, no. 10 (May 16, 2019): 1606. http://dx.doi.org/10.3390/ma12101606.

Повний текст джерела
Стилі APA, Harvard, Vancouver, ISO та ін.
Анотація:
The cooperative self-assembly of nanoparticles and amphiphilic block copolymers has attracted increasing interests as it offers effective routes to achieve nanocomposite supramolecular structures with desired structure and properties. The incorporation of nanoparticles usually tunes the self-assembly structure of block copolymers, as the copolymer–nanoparticle interactions may change the relative volume ratio of hydrophobic block/hydrophilic block copolymers. It should be noted that the micro-size length and the strong nonpolar feature of carbon nanotubes (CNTs) may cause the block copolymer–CNT interactions to differ from the the block copolymer–nanoparticle interactions. Herein, we show that the diameter of CNTs and the copolymer/CNT ratio have a profound effect on the self-assembly behavior of amphiphilic block copolymers. Upon the addition of carboxylated multi-walled carbon nanotubes (c-MWCNTs, diameter <8 nm,) to the methoxy polyethylene glycol-poly (D,L-lactic acid) (MPEG-PDLLA) solution, it is difficult to observe the c-MWCNTs directly in TEM images. However, it has been found that they form supramolecular nanocomposite structures with MPEG-PDLLA. Moreover, these supramolecular structures transform from core–shell spherical micelles into rod-like micelles and then into large composite aggregates with the increase of the c-MWCNT addition. However, in the case of the addition of c-MWCNTs with a diameter of 30–50 nm, the dispersed c-MWCNTs and spherical core–shell micelles could be observed simultaneously in the TEM images at a low c-MWCNT addition, and then the micelle structure disappeared and only well-dispersed c-MWNTs were observed in TEM images at a high c-MWCNT addition. A possible model was proposed to explain the rule of CNTs participating in the formation of copolymer/CNT nanocomposite structures. It was also shown that as-prepared copolymer/CNT supramolecular nanocomposites could be used as drug carriers, enabling the adjustment of the drug loading and release time.
8

Choi, Young Joo, Hyeong Min Jin, Bong Hoon Kim, Ju Young Kim, and Sang Ouk Kim. "Self-Assembly Nanofabrication via Mussel-Inspired Interfacial Engineering." Applied Mechanics and Materials 229-231 (November 2012): 2749–52. http://dx.doi.org/10.4028/www.scientific.net/amm.229-231.2749.

Повний текст джерела
Стилі APA, Harvard, Vancouver, ISO та ін.
Анотація:
We present that polydopamineassistedinterfacial engineering can be synergistically integratedwith block copolymer lithography for surface nanopatterningof low-surface-energy substrate materials, includingTeflon, graphene, and gold. Block copolymer lithography is aself-assembly based nanofabrication that holds greatpromise for sub-10-nm scale patterning. The directed self-assemblyof block copolymers into device-oriented nanopatternsgenerally requires organic modification of a substrate surface.In this work, the versatility of the polydopamine treatment was demonstrated by the surface modification.
9

Tirrell, Matthew V., and Alexander Katz. "Self-Assembly in Materials Synthesis." MRS Bulletin 30, no. 10 (October 2005): 700–704. http://dx.doi.org/10.1557/mrs2005.205.

Повний текст джерела
Стилі APA, Harvard, Vancouver, ISO та ін.
Анотація:
AbstractThe synthesis of materials via self-assembly typically involves the spontaneous and reversible organization of small building blocks for the purpose of creating conglomerate structures over larger length scales. This introductory article describes self-assembly processes on several length scales, from subnanometer up to millimeter scales, and briefly summarizes some of the incredible diversity of materials that exhibit selfassembly. Articles in this issue cover self-assembly using zeolitic structures, organic molecular crystals, block copolymers, surfactants, mesoscale templates, and soluble crystallization additives. Keywords: block copolymers, materials synthesis, self-assembly, surfactants, templates, zeolites.
10

Bailly, Nathalie, Gwenaelle Pound-Lana, and Bert Klumperman. "Synthesis, Characterization, and Self-Assembly of Poly(N-vinylpyrrolidone)-block-poly(vinyl acetate)." Australian Journal of Chemistry 65, no. 8 (2012): 1124. http://dx.doi.org/10.1071/ch12185.

Повний текст джерела
Стилі APA, Harvard, Vancouver, ISO та ін.
Анотація:
Poly(N-vinylpyrrolidone)-block-poly(vinyl acetate) (PVP-b-PVAc) block copolymers of varying molar mass and hydrophobic block lengths were synthesized by xanthate-mediated radical polymerization. In order to control the molar mass of the hydrophilic PVP block, a xanthate chain transfer agent, S-(2-cyano-2-propyl) O-ethyl xanthate, was used. The PVP-b-PVAc block copolymer is composed of a hydrophilic and hydrophobic segment, and has the ability to self-assemble in aqueous solution. The PVP-b-PVAc block copolymers were characterized by 1H NMR spectroscopy to confirm their self-assembly in water. The critical micelle concentration was determined by fluorescence spectroscopy. A combination of dynamic light scattering, transmission electron microscopy, and static light scattering was used to further characterize the self-assembly of the block copolymers in water.
Більше джерел
Також вас можуть зацікавити розширені добірки на тему "Self-Assembly of block copolymers" для конкретних типів джерел:
Статті в журналах Дисертації Книги

Дисертації з теми "Self-Assembly of block copolymers":

1

Valverde, Serrano Clara. "Self-assembly behavior in hydrophilic block copolymers." Phd thesis, Universität Potsdam, 2011. http://opus.kobv.de/ubp/volltexte/2011/5416/.

Повний текст джерела
Стилі APA, Harvard, Vancouver, ISO та ін.
Анотація:
Block copolymers are receiving increasing attention in the literature. Reports on amphiphilic block copolymers have now established the basis of their self-assembly behavior: aggregate sizes, morphologies and stability can be explained from the absolute and relative block lengths, the nature of the blocks, the architecture and also solvent selectiveness. In water, self-assembly of amphiphilic block copolymers is assumed to be driven by the hydrophobic. The motivation of this thesis is to study the influence on the self-assembly in water of A b B type block copolymers (with A hydrophilic) of the variation of the hydrophilicity of B from non-soluble (hydrophobic) to totally soluble (hydrophilic). Glucose-modified polybutadiene-block-poly(N-isopropylacrylamide) copolymers were prepared and their self-assembly behavior in water studied. The copolymers formed vesicles with an asymmetric membrane with a glycosylated exterior and poly(N-isopropylacrylamide) on the inside. Above the low critical solution temperature (LCST) of poly(N-isopropylacrylamide), the structure collapsed into micelles with a hydrophobic PNIPAM core and glycosylated exterior. This collapse was found to be reversible. As a result, the structures showed a temperature-dependent interaction with L-lectin proteins and were shown to be able to encapsulate organic molecules. Several families of double hydrophilic block copolymers (DHBC) were prepared. The blocks of these copolymers were biopolymers or polymer chimeras used in aqueous two-phase partition systems. Copolymers based on dextran and poly(ethylene glycol) blocks were able to form aggregates in water. Dex6500-b-PEG5500 copolymer spontaneously formed vesicles with PEG as the “less hydrophilic” barrier and dextran as the solubilizing block. The aggregates were found to be insensitive to the polymer's architecture and concentration (in the dilute range) and only mildly sensitive to temperature. Variation of the block length, yielded different morphologies. A longer PEG chain seemed to promote more curved aggregates following the inverse trend usually observed in amphiphilic block copolymers. A shorter dextran promoted vesicular structures as usually observed for the amphiphilic counterparts. The linking function was shown to have an influence of the morphology but not on the self-assembly capability in itself. The vesicles formed by dex6500-b-PEG5500 showed slow kinetics of clustering in the presence of Con A lectin. In addition both dex6500-b-PEG5500 and its crosslinked derivative were able to encapsulate fluorescent dyes. Two additional dextran-based copolymers were synthesized, dextran-b-poly(vinyl alcohol) and dextran-b-poly(vinyl pyrrolidone). The study of their self-assembly allowed to conclude that aqueous two-phase systems (ATPS) is a valid source of inspiration to conceive DHBCs capable of self-assembling. In the second part the principle was extended to polypeptide systems with the synthesis of a poly(N-hydroxyethylglutamine)-block-poly(ethylene glycol) copolymer. The copolymer that had been previously reported to have emulsifying properties was able to form vesicles by direct dissolution of the solid in water. Last, a series of thermoresponsive copolymers were prepared, dextran-b-PNIPAMm. These polymers formed aggregates below the LCST. Their structure could not be unambiguously elucidated but seemed to correspond to vesicles. Above the LCST, the collapse of the PNIPAM chains induced the formation of stable objects of several hundreds of nanometers in radius that evolved with increasing temperature. The cooling of these solution below LCST restored the initial aggregates. This self-assembly of DHBC outside any stimuli of pH, ionic strength, or temperature has only rarely been described in the literature. This work constituted the first formal attempt to frame the phenomenon. Two reasons were accounted for the self-assembly of such systems: incompatibility of the polymer pairs forming the two blocks (enthalpic) and a considerable solubility difference (enthalpic and entropic). The entropic contribution to the positive Gibbs free energy of mixing is believed to arise from the same loss of conformational entropy that is responsible for “the hydrophobic effect” but driven by a competition for water of the two blocks. In that sense this phenomenon should be described as the “hydrophilic effect”.
Blockcopolymere erfahren ein stetig wachsendes Interesse, was an der steigenden Anzahl an Publikationen zu diesem Thema erkennbar ist. Zahlreiche Studien zu amphiphilen Blockcopolymeren haben dabei einige grundlegende Erkenntnisse über deren chemisches und physikalisches Verhalten, vor allem über die Selbstorganisation, hervorgebracht. So können die Größe, die verschiedenen Morphologien und auch die Stabilität der gebildeten Aggregate anhand der relativen und absoluten Blocklängen, die chemischen Struktur der Blöcke, der molekularen Architektur und der Eigenschaften des verwendeten Lösungsmittel erklärt werden. Im speziellen Fall des Wassers als Lösungsmittel bist die Selbstorganisation amphiphiler Blockcopolymere durch den hydrophoben Effekt bedingt. Dieser Arbeit liegt das Interesse an der Selbstorganisation in wässrigem Medium von Blockcopolymeren des Typs A-b-B mit A als hydrophilem Block und B als Block mit variierender Hydrophilie bzw. Hydrophpobie von unlöslich bis vollständig löslich zugrunde. Durch Variation dieser Eigenschaften von Block B soll dessen Einfluss auf das Selbstorganisationsverhalten untersucht werden. Dazu wurden mit Glucose modifizierte Polybutadien-block-Poly(N-Isopropylacrylamid)-Copolymere hergestellt und deren Selbstorganisation in Wasser untersucht. Die Copolymere bilden Vesikel mit einer asymmetrischen Membran, wobei im äußeren Bereich glycolysierte Gruppen und im inneren Bereich Poly(N-Isopropylacrylamid) (PNIPAM) vorliegen. Beim Überschreiten der low critical solution temperature (LCST) kollabiert die vesikuläre Struktur unter Bildung von Mizellen mit einem hydrophoben PNIPAM-Mizellinneren und nach außen gerichteten glycolysierten Blöcken. Diese strukturelle Umwandlung ist reversibel. Die Strukturen zeigten außerdem eine temperaturabhängige Wechselwirkung mit L-Lectin-Proteinen und die Möglichkeit zur Einkapselung organischer Moleküle konnte belegt werden. Des weiteren wurden verschiedene Gruppen von Blockcopolymeren mit zwei hydrophilen Blöcken synthetisiert (double hydrophilic block copolymers – DHBC). Die Blöcke dieser Systeme waren entweder Biopolymere oder Polymerchimäre, die in wässrigen Zwei-Phasen-Trennverfahren eingesetzt werden. Polymere, die auf Dextran- und Poly(ethylenglycol)-Blöcken basieren, zeigen Aggregatbildung in wässriger Phase. Dex6500-b-PEG5500 bildet spontan Vesikel mit PEG als „weniger hydrophilem“ Bestandteil und Dextran als löslichem Block. Die Bildung dieser Vesikel zeigte keine Emfpindlichkeit gegenüber einer Veränderung der Polymerarchitektur und der Konzentration, und nur eine geringe Sensitivität gegenüber Temperaturänderungen. Veränderungen der Blocklängen dagegen beeinflussten die Selbstorganisation und führten zu unterschiedlichen Morphologien. Längere PEG-Blöcke bevorzugten dabei die Bildung eher gekrümmter Aggregate, entgegen dem Trend, der gewöhnlicherweise für amphiphile Blockcopolymere beobachtet wird. Die Verkürzung des Dextran-Blocks fördert die Ausbildung vesikulärer Strukturen, was dem Verhalten der amphiphilen Gegenspieler der DHBC-Systeme entspricht. Die funktionelle Gruppe zur Verbindung der beiden Blöcke hat zwar einen Einfluss auf die Morphologie der gebildeten Aggregate, nicht jedoch auf die eigentliche Fähigkeit der Systeme zur Selbstorganisation. Die Dex6500-b-PEG5500-Vesikel wiesen zudem eine langsame Bildungskinetik in Gegenwart von Con-A-Lectin auf. Des Weiteren waren sowohl Dex6500-b-PEG5500 als auch das quervernetzte Derivate dieses Copolymers in der Lage, Fluoreszenzfarbstoffe einzulagern. Um zu zeigen, dass wässrige Zwei-Phasen-Systeme (aqueous two phase systems – ATPS) eine belastbare Grundlage für die Untersuchung und Entwicklung selbstorganisierender DHBC-Systeme sind, wurden weitere Dextran-basierte Copolymere synthetsisiert: Dextran-b-Poly(vinylalokohol) und Detran-b-Poly(vinylpyrrolidon). In einem zweiten Teil dieser Arbeit wurde das zuvor erarbeitete Prinzip auf auf Polypeptidsysteme ausgeweitet. Dazu wurde ein Poly(N-Hydroxyethylglutamin)-block-Poly(ethylenglycol)-Copolymer hergestellt. Dieses Copolymer, dessen emulgierenden Eigenschaften bereits bekannt waren, wies unmittelbar nach Lösung des Feststoffes in Wasser Vesikelbildung auf. In einem dritten Teil der Studie wurden thermoresponsive Copolymere hergestellt und untersucht: Dextran-b-PNIPAMm. Unterhalb der LCST konnte die Bildung von Aggregaten nachgewiesen werden, deren Struktur nicht zweifelsfrei entschlüsselt werden konnte, wobei jedoch zahlreiche Hinweise auf eine vesikuläre Struktur hindeuten. Oberhalb der LCST wurde durch die Kollabierung der PNIPAM-Ketten die Bildung stabiler Strukturen mit Radien von mehreren hundert Nanometern induziert, deren weitere Entwicklung durch eine weitere Temperaturerhöhung gefördert werden konnte. Durch Rückkühlung in den Temperaturebereich unterhalb der LCST konnten die zuvor beobachteten Aggregate reversibel zurückgebildet werden. Das Selbstorganisationsverhalten von DHBC, unabhängig vom Einfluss des pH-Werts, der Ionenstärke oder der Temperatur are bisher nur in sehr geringem Umfang Gegenstand wissenschaftlicher Veröffentlichungen. Diese Arbeit stellt damit den ersten umfassenden Beitrag zur systematischen Erarbeitung dieses Phänomens dar. Es konnten dabei zwei Ursachen für die beobachteten Selbstorganisationseffekte bestimmt werden: die Inkompatibilität der beiden Polymerblöcke (enthalpischer Effekt) und der Unterschied in deren Löslichkeit (enthalpische und entropische Effekte). Der entropische Beitrag zur positiven Gibbs’schen Freien Mischungsenergie wird dem selben Verlust konformativer Entropie zugeordnet, der auch für den hydrophoben Effekt verantwortlich ist, allerdings angetrieben durch einen Wettbewerb der beiden Polymerblöcke um das Wasser. In diesem Sinne kann man das beobachtete Phänomen als „hydrophilen Effekt“ bezeichnen.
2

Cheng, Li-Chen Ph D. Massachusetts Institute of Technology. "Templated self-assembly of novel block copolymers." Thesis, Massachusetts Institute of Technology, 2019. https://hdl.handle.net/1721.1/122156.

Повний текст джерела
Стилі APA, Harvard, Vancouver, ISO та ін.
Анотація:
Thesis: Ph. D., Massachusetts Institute of Technology, Department of Materials Science and Engineering, 2019
Cataloged from PDF version of thesis.
Includes bibliographical references.
Self-assembly of block copolymers (BCPs) is emerging as a promising route for numerous technological applications to fabricate a variety of nanoscopic structures. The resulting feature sizes range from a few to several hundred nanometers, and are readily tunable by varying the molecular weights of block copolymers. Directed self-assembly of block copolymer is an effective way to pattern periodic arrays of features with long-range order, to generate complex patterns, and to multiplicatively increase the pattern density and resolution that are far beyond the limit of conventional lithography. Despite of the significant progress in the area of directed self-assembly in recent years, critical research problems regarding the dimension scalability toward sub-10-nm regime and large feature sizes on hundreds of nanometers scale as well as the capability of generating complex device-oriented patterns remain challenging. In this thesis, BCP systems, including high-v BCPs that are capable of self-assembling into extreme small and large feature sizes as well as those with more complex block architectures, are identified and studied in order to understand how those materials may be processed and directed selfassembly to bridge the patterning size spectrum between nano- and micro-fabrication. Another focus is placed on the scientific exploration of directed self-assembly of triblock terpolymers and the investigation on the mechanisms that regulate the scaling and geometry of self-assembled patterns. A comprehensive understanding about self-assembly of BCP thin films will enable developing device-oriented geometries, manipulating BCPs phase behavior, and incorporating new functional materials for a wider range of applications. In the meanwhile, optimizing the processing condition of self-assembly of various BCPs is essential to confirm viability of the directed self-assembly of block copolymers process in manufacturing.
by Li-Chen Cheng.
Ph. D.
Ph.D. Massachusetts Institute of Technology, Department of Materials Science and Engineering
3

Mohd, Yusoff Siti Fairus. "Crystallization-driven self-assembly of polyferrocenylsilane-based block copolymers." Thesis, University of Bristol, 2011. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.546192.

Повний текст джерела
Стилі APA, Harvard, Vancouver, ISO та ін.
4

Jung, Yeon Sik. "Templated self-assembly of siloxane block copolymers for nanofabrication." Thesis, Massachusetts Institute of Technology, 2009. http://hdl.handle.net/1721.1/52791.

Повний текст джерела
Стилі APA, Harvard, Vancouver, ISO та ін.
Анотація:
Thesis (Ph. D.)--Massachusetts Institute of Technology, Dept. of Materials Science and Engineering, 2009.
This electronic version was submitted by the student author. The certified thesis is available in the Institute Archives and Special Collections.
Cataloged from student submitted PDF version of thesis.
Includes bibliographical references.
Monolayer patterns of block copolymer (BCP) microdomains have been pursued for applications in below sub-30 nm nanolithography. BCP selfassembly processing is scalable and low cost, and is well-suited for integration with existing semiconductor fabrication techniques. The two critical issues are how to obtain reliable long-range ordering of features with minimum defect densities and how to successfully transfer the patterns into other functional materials. Exceptionally well-ordered and robust nanoscale patterns can be made from poly(styrene-b-dimethylsiloxane) (PS-PDMS) BCPs, which have a very large Flory-Huggins interaction parameter between the blocks compared to other commonly used BCPs. Cylinder- or sphere-forming BCP films were spincoated over silicon substrates patterned with shallow steps using optical lithography or nanoscale posts made by electron-beam lithography, and solvent-annealed to induce ordering. This generates patterns with a correlation length of at least several micrometers. The annealed film was treated with plasma to obtain oxidized PDMS patterns with a lateral dimension of 14 - 18 nm. These can be used as an etch mask or an easily removable template for patterning functional materials. Solvent vapor treatments can tune the pattern dimension and morphology. Different degrees of solvent uptake in BCP films during solvent-annealing can manipulate the interfacial interaction between the two blocks, and a mixed solvent vapor can change the effective volume fraction of each block. The self-assembled patterns can be transferred into various kinds of functional materials.
(cont.) For example, arrays of parallel lines were used as a mask to pattern poly(3,4-ethylenedioxythiophene):poly(styrenesulfonate) (PEDOT:PSS) conducting polymer thin films. The resulting PEDOT:PSS nanowire array was used as an chemiresistive-type ethanol-sensing device. Metallic films such as Ti, Pt, Ta, W, and magnetic Co and Ni were structured using a pattern-reversal process. Coercivity enhancements were observed for the fabricated ferromagnetic nanostructures such as wires, rings, and antidots. These functional nanostructures can be utilized for a variety of devices such as high-density and high performance sensor or memory devices.
by Yeon Sik Jung.
Ph.D.
5

Cowie, Lauren. "The synthesis and self-assembly of MPC block copolymers." Thesis, Durham University, 2013. http://etheses.dur.ac.uk/7341/.

Повний текст джерела
Стилі APA, Harvard, Vancouver, ISO та ін.
Анотація:
Biocompatible and biodegradable poly(lactide)-2-methacryloyloxyethyl phosphorylcholine (PLA-PMPC) amphiphilic block copolymers were synthesized by a combination of Ring Opening Polymerization (ROP) and Reversible Addition-Fragmentation Chain Transfer (RAFT) polymerization techniques. The PLA-macroRAFT agent was synthesized by the derivatization of PLA-OH with RAFT agent 4-cyano-4-(phenylcarbonothioylthio)pentanoic acid (CPADB) achieving high levels of functionalization and narrow weight distributions (PDI range of 1.02-1.17). PLA-PMPC with varied MPC block lengths were synthesized yielding polymers with a narrow polydispersity PDI = 1.16-1.21. Triblock copolymers PMPC-PLA-PMPC with varying hydrophilic weight ratios were synthesized following an analogous method, the polymerizations were shown to be controlled with PDI’s of 1.24 and 1.36. PLA-PMPC block copolymers with varied compositions were self-assembled using several techniques to target different morphologies. Nanostructures were characterised by DLS and TEM. Block copolymers with a larger PLA block length were shown to generate smaller aggregates i.e. micelles. The morphologies observed for the various block copolymers were consistent amongst different preparative techniques. Vesicle structures were reproducible by the self-assembly of PMPC50-PLA51-PMPC50, however, by preparing nanoparticles by direct dissolution micelles formed. The block copolymers were shown to encapsulate a hydrophobic dye in aqueous media thereby demonstrating its potential drug delivery applications.
6

BERTANI, DANIELA. "Synthesis and self-assembly of biocompatible amphiphilic block copolymers." Doctoral thesis, Università degli Studi di Milano-Bicocca, 2018. http://hdl.handle.net/10281/199109.

Повний текст джерела
Стилі APA, Harvard, Vancouver, ISO та ін.
Анотація:
Il drug delivery attira molto interesse a causa della necessità di migliorare efficienza e selettività delle terapie farmacologiche. Capsule polimeriche per i farmaci sono una strategia promettente per prolungarne i tempi di circolazione, migliorarne il trasporto nel sangue, e modularne nel tempo il rilascio. In questo ambito, l’organizzazione spontanea dei copolimeri a blocchi (CB) in nanoparticelle (NP) compartimentalizzate in ambiente acquoso è uno strumento potente per la fabbricazione di sistemi per il drug delivery. In questa tesi vengono investigati la sintesi e l’autoassemblaggio (AS) controllati di una serie di CB anfifilici contenenti blocchi idrofilici biocompatibili e biomimetici. Nel Cap. 3 viene presentato un quadro completo del comportamento di AS di PS-b-PDMA in H2O da DMF. E’ stato preparato un set di campioni con pesi molecolari compresi fra 10 kDa e 57 kDa e fPDMA comprese fra 0.06 e 0.75, e le NP sono state caratterizzate con DLS, TEM, CEM, CET, SEM e AFM. Viene proposta una mappa morfologica, dove le morfologie dominanti sono state correlate con la caratteristiche chimiche dei CB. In particolare, quando fPDMA < 0.15, è stata osservata la formazione di particelle porose con diametri fino ad alcuni micron che assumono una fase spugnosa, stabile alla liofilizzazione. Nel Cap. 4, una serie di CB biocompatibili e biodegradabili di PEO-b-PLA sono stati sintetizzati tramite ROP controllata di lattide catalizzata da DBU. Il focus di ricerca era sull’effetto del solvente non selettivo sull’AS: NP ottenute da ACT, DX, THF e DMF sono state analizzate con DLS, CEM e CET. Dimensioni e PDI aumentavano nell’ordine ACT < DX < THF ~ DMF. Le NP sono state classificate in tre cluster: micelle (piccolo raggio, basso PDI), polimersomi (medio raggio, medio PDI), e micelle composte (grande raggio, grande PDI). Mentre ACT e DX portano alla formazione preferenziale di micelle, il THF permette di accedere a uno spazio morfologico molto più ampio. Infine, la DMF favorisce fenomeni di aggregazione di secondo ordine. Nel Cap. 5 vengono valutati la sintesi controllata, la funzionalizzazione terminale e la formazione di di- e triblocchi di polimeri a base di PEtOx biocompatibile tramite una combinazione di ROP e RAFT. Un blocco di PEtOx25 è stato sintetizzato con successo tramite CROP di 2-etil-2-ossazolina con buon controllo; è stato poi usato come macroCTA per la polimerizzazione sequenziale di Sty e t-BA per ottenere il copolimero a tre blocchi PEtOx-b-PS-b-PtBA. Vengono presentati risultati preliminari sul SA in etanolo come solvente selettivo per i blocchi di PEtOx e PtBA, ma non PS. Nel Cap. 6 è stato studiato l’effetto morfogenico di ACT, DX e DMF sul SA di PS-b-PDMA e PEO-b-PLA usando il rotore molecolare AzeNaph-1 come sonda di viscosità per il monitoraggio in situ dell’aggregazione dei CB. L’evoluzione della viscosità in funzione del contenuto di H2O in PS-b-PDMA è simile sia in DMF che DX: all’aggiunta di H2O, le catene di PS collassano rapidamente, formando core prevalentemente vetrosi. Coerentemente, il DLS mostra poca variazione di dimensioni delle NP fra i due solventi. Anche PEO-b-PLA forma domini vetrosi in DMF/H2O, ma non in ACT o DX. Al contrario, la viscosità locale del core è molto minore in ACT e DX che in DMF su tutto il range di frazione di H2O, ed è dipendente dal tempo. Questa aumentata mobilità molecolare promuove la differenziazione delle NP formate. Infine, nel Cap. 7 viene esplorato l’AS indotto da polimerizzazione di CB anfifilici basati su glicopolimeri. Tre campioni di PAGA con DP = 25, 50 e 75 sono stati polimerizzati in H2O/MeOH tramite RAFT, con ottimo controllo. L’ottimizzazione delle condizioni di reazioni ha permesso di usare PAGA25 e PAGA50 come stabilizzanti e macroCTA per l’estensione di catena con BA in H2O/MeOH. Il controllo sulla polimerizzazione è stato basso, ma sono state ottenute NP sferiche, stabili e monodisperse.
Drug delivery is a trending topic in current research due to the need to improve therapeutic efficiency and selectivity. Polymeric encapsulants for drugs are a promising strategy to prolong circulation times, enhance hydrophobic drug transport through the blood stream, and modulate drug release over time. In this field, amphiphilic block copolymers’ (BCs) spontaneous organization in compartimentalized nanoparticles (NPs) in water is a powerful tool for the fabrication of drug delivery systems. In this Doctoral thesis, the controlled synthesis and self-assembly (S-A) of a series of amphiphilic BCs containing biocompatible, stealthy hydrophilic blocks were investigated. Controlled polymerization techniques were employed to prepare copolymers with narrow molecular weight distributions. In Chapter 3, a complete picture of the previously unreported S-A behaviour of PS-b-PDMA in water from DMF is drawn. A comprehensive sample set spanning molecular weights from 10 kDa to 57 kDa and hydrophilic volume fractions fPDMA from 0.06 to 0.75 was prepared by sequential RAFT, and NPs were characterized by DLS, TEM, CEM, CET, SEM, and AFM. A morphology map is proposed, where predominant morphologies were correlated with BC chemical characteristics. In particular, stable hollow particles with diameters up to several microns when fPDMA drops below 0.15 are formed. Micron-large porous particles exhibiting a sponge phase which can withstand lyophilisation were observed. In Chapter 4, a series of biocompatible and biodegradable PEO-b-PLA BCs were synthesized by controlled ROP of lactide catalyzed by non-toxic DBU. The research focus was on the effect of the non-selective solvent on S-A: NPs obtained from ACT, DX, THF, DMF were analyzed by DLS, CEM and CET. Both size and PDI increased in the order ACT < DX < THF ~ DMF. NPs were classified into three clusters, labeled micelles (small size, low PDI), polymersomes (medium size, medium-low PDI) and large compound micelles (large size, large PDI). While ACT and DX yielded mostly micelles, THF allowed to access a much broader morphological space. Finally, DMF favoured second-order aggregation phenomena. In Chapter 5, controlled synthesis, chain-end functionalization and di- and triblock formation of biocompatible PEtOx-based polymers by a combination of ROP and RAFT techniques were evaluated. Biocompatible PEtOx25 blocks were successfully synthesized by CROP of 2-ethyl-2-oxazoline with good control. PEtOx25 was used as a macroCTA for the sequential polymerization of a Sty and tBA to yield a PEtOx25-b-PS50-b-PtBA25 triblock copolymer. Preliminary results on S-A in ethanol as a selective solvent for both PEtOx and PtBA, but not for PS, are presented. In Chapter 6, the morphogenic effect of ACT, DX and DMF on PS-b-PDMA and PEO-b-PLA S-A was studied using molecular rotor AzeNaph-1 as a local viscosity probe for the in situ monitoring of BC aggregation. Evolution of viscosity as a function of water content in PS-b-PDMA was similar both in DMF and DX: upon the addition of H2O, PS chains rapidly collapsed in NP cores, which were largely glassy. Consistently, DLS shows little variation on particle size between the two solvents. PEO113-b-PLAx also formed glassy domains in DMF/H2O, but not in ACT or DX. Contrarily, local core viscosity was much lower in ACT and DX than in DMF over the whole H2O fraction range, and was time-dependent. This increased chain mobility promoted the differentiation of NP formation. Finally, in Chapter 7, polymerization-induced S-A of glycopolymer-based amphiphilic BCs was investigated. Three PAGA samples with DP = 25, 50 and 75 were polymerized in H2O/methanol mixture by RAFT, with remarkable control. Optimization of reaction conditions allowed the use of PAGA25 and PAGA50 as stabilizers and macroCTAs for chain-extension with n-butylacrylate (BA) in methanol/H2O environment. Control on the polymerization was poor, but stable and monodisperse spherical NPs were obtained.
7

Gomes, Correia Cindy. "Directed self-assembly strategies for orientation-controlled block copolymers for advanced lithography." Thesis, Bordeaux, 2019. http://www.theses.fr/2019BORD0393.

Повний текст джерела
Стилі APA, Harvard, Vancouver, ISO та ін.
Анотація:
L’objectif de ce travail était de mettre en évidence le potentiel du PDMSBb-PS pour des applications en nanolithographie avancée. Pour cela, nous avons fourni une compréhension du comportement d’auto-assemblage du PDMSB-b-PS en masse et en film mince. Nous avons réalisé l’auto-assemblage de ce copolymère semicristallin en cylindre et gyroïde bien définis avec des périodicités inférieures à 20 nm grâce à un paramètre d’interaction de Flory-Huggins élevé (Chapitre 2). Nous avons par la suite proposé une approche pour obtenir des lamelles perpendiculaires du PDMSB-b-PS en film mince grâce à l’utilisation de sur-couches neutres réticulables. La polyvalence de cette approche a été démontrée à l’aide de CPBs de masses moléculaires différentes et s’est ensuite étendue à la formation d’empilements via un processus d’auto-assemblage itératif (chapitre 3). Enfin, nous avons réticulé la surcouche neutre à l’aide d’agents photo-sensibles ce qui nous a permis d’obtenir un motif par photolithographie au-dessus du film CPB. Ainsi, il a été possible de contrôler l’orientation du CPB à des endroits spécifiques du film (Chapitre 4)
The objective of our work was to highlight the potential of the high-χ PDMSB-b-PS BCP for advanced nanolithography applications. For this purpose, we have demonstrated the ability of our system to self-assemble into well-defined nanostructures in bulk and we have performed the self-assembly of cylinder- and gyroid-forming PDMSB-b-PS BCPs in thin film using industrially-friendly processes (Chapter 2). With the aim of controlling the out-of-plane orientation of lamellar-forming PDMSB-b-PS BCPs in thin film, we have proposed an innovative approach relying on the use of crosslinkable neutral TC layers. The versatility of this approach was demonstrated using BCPs having different macromolecular characteristics and extended to the formation of multi-layer stacks through an iterative self-assembly process (Chapter 3). Taking advantage of the crosslinking ability of our TC material, we have outlined the patterning ability of the TCs using photosensitive crosslinking agents. The patterning of neutral TCs above the lamellar-forming PDMSB-b-PS BCPs further allowed a control of the orientation of the PDMSB-b-PS domains in specific areas of the film (Chapter 4)
8

Evangelio, Araujo Laura. "Directed self-assembly of block copolymers on chemically nanopatterned surfaces." Doctoral thesis, Universitat Autònoma de Barcelona, 2017. http://hdl.handle.net/10803/406119.

Повний текст джерела
Стилі APA, Harvard, Vancouver, ISO та ін.
Анотація:
La tesi doctoral titulada “Auto-assemblatge de copolímers de bloc per modificació química de la superfície”, presenta com a objectiu principal el desenvolupament, implementació i caracterització d’un mètode de guiatge de copolímers de bloc basat en la modificació química de la superfície. El desenvolupament d’aquest mètode de nanofabricació contribueix a la futura generació de dispositius i circuits nanoelectrònics. Primer de tot, es presenten els aspectes generals sobre l’auto-assemblatge dirigit de copolímers de bloc, així com el seu rol dins del futur de la nanoelectrònica comparat amb altres tecnologies emergents. Després, per tal d’entendre i determinar les interaccions que tenen lloc durant el procés d’auto-assemblatge, es dóna una visió general sobre els processos químics i físics que tenen lloc en les pel·lícules primes de copolímers de bloc. La part principal de la tesi es focalitza en l’estudi, desenvolupament i implementació d’un mètode de guiatge químic per tal de dirigir l’auto-assemblatge de copolímers de bloc. A banda d’estudiar el procés experimental, també es caracteritzen els mecanismes que condueixen l’alineament i s’introdueixen a un model per simular el procés d’auto-assemblatge dirigit. A més, també es presenta la transferència del procés a una línia pilot industrial de fabricació de circuits integrats. La implementació del procés de guiatge químic s’ha provat no únicament amb materials comercials, sinó també amb nous sistemes polimèrics que permeten arribar a mides per sota dels 10 nm. Per aquests sistemes, es defineix un nou mètode de guiatge basat en la combinació de modificacions topogràfiques i químiques. Per tal d’entendre millor el procés, s’estudien tècniques específiques de metrologia. En particular, mitjançant tècniques d’alta energia de rajos X, es descriuen les principals diferències entre patrons químics de guiatge. D’altra banda, les propietats nanomecàniques dels diferents dominis del copolímer es determinen mitjançant el mode peak force tapping de la microscòpia de força atòmica. Finalment, es mostra un mètode per transferir els motius del copolímer al substrat. Aquest es basa en la infiltració d’un domini del copolímer. La infiltració canvia les propietats del material i el fa més resistiu al gravat amb oxigen. D’altra banda, i com a aplicació final, es presenta un procés de fabricació de ressonadors nanomecànics, basats en el procés d’auto-assemblatge de copolímers de bloc amb infiltració.
The thesis entitled “Directed self-assembly of block copolymers on chemically nano-patterned surfaces”, aboard the challenge of the development, implementation and characterization of a chemical epitaxy process to direct self-assemble block copolymers. The development of this nanofabrication method contributes to the next generation of nanoelectronic devices and circuits. Firstly, the main aspects of directed self-assembly of block copolymers and its role and status in the future of nanoelectronics is presented, and compared with other powerful technologies. Then, a general overview about the physics and chemistry involved in block copolymer thin films is presented, in order to understand and determine the interactions taking place during the DSA process. The main part of the thesis is focused on the study, development and implementation of a chemical epitaxy approach to guide the self-assembly of block copolymers. Apart from the process development, the mechanisms which drive the block copolymer alignment are characterized and simulated into a DSA model. Moreover, the process transfer to a more industrial pilot line is presented. The implementation of the chemical epitaxy process is addressed not only with commercial block copolymers, but also with new polymer systems which allow getting sub- 10 nm resolution. For these systems, a new guiding method is presented based on the combination of a chemical and graphoepitaxy approach. To better understand the DSA process, dedicated metrology methods are also studied. In particular, by using high-energy X-ray techniques it is possible to describe the main characteristics of the chemical guiding patterns. On the other hand, the nanomechanical properties of block copolymer domains are studied by using the peak force tapping mode in atomic force microscopy. A reliable method to pattern transfer the block copolymer features into the substrate is showed. It is based on infiltrating one block copolymer domain and enhancing thus, its resistivity to plasma etching. Finally, as a final application, a novel fabrication process of a nanowire mechanical resonator by means of DSA and infiltration is presented.
9

Weiß, Jan. "Synthesis and self-assembly of multiple thermoresponsive amphiphilic block copolymers." Phd thesis, Universität Potsdam, 2011. http://opus.kobv.de/ubp/volltexte/2011/5336/.

Повний текст джерела
Стилі APA, Harvard, Vancouver, ISO та ін.
Анотація:
In the present thesis, the self-assembly of multi thermoresponsive block copolymers in dilute aqueous solution was investigated by a combination of turbidimetry, dynamic light scattering, TEM measurements, NMR as well as fluorescence spectroscopy. The successive conversion of such block copolymers from a hydrophilic into a hydrophobic state includes intermediate amphiphilic states with a variable hydrophilic-to-lipophilic balance. As a result, the self-organization is not following an all-or-none principle but a multistep aggregation in dilute solution was observed. The synthesis of double thermoresponsive diblock copolymers as well as triple thermoresponsive triblock copolymers was realized using twofold-TMS labeled RAFT agents which provide direct information about the average molar mass as well as residual end group functionality from a routine proton NMR spectrum. First a set of double thermosensitive diblock copolymers poly(N-n-propylacrylamide)-b-poly(N-ethylacrylamide) was synthesized which differed only in the relative size of the two blocks. Depending on the relative block lengths, different aggregation pathways were found. Furthermore, the complementary TMS-labeled end groups served as NMR-probes for the self-assembly of these diblock copolymers in dilute solution. Reversible, temperature sensitive peak splitting of the TMS-signals in NMR spectroscopy was indicative for the formation of mixed star-/flower-like micelles in some cases. Moreover, triple thermoresponsive triblock copolymers from poly(N-n-propylacrylamide) (A), poly(methoxydiethylene glycol acrylate) (B) and poly(N-ethylacrylamide) (C) were obtained from sequential RAFT polymerization in all possible block sequences (ABC, BAC, ACB). Their self-organization behavior in dilute aqueous solution was found to be rather complex and dependent on the positioning of the different blocks within the terpolymers. Especially the localization of the low-LCST block (A) had a large influence on the aggregation behavior. Above the first cloud point, aggregates were only observed when the A block was located at one terminus. Once placed in the middle, unimolecular micelles were observed which showed aggregation only above the second phase transition temperature of the B block. Carrier abilities of such triple thermosensitive triblock copolymers tested in fluorescence spectroscopy, using the solvatochromic dye Nile Red, suggested that the hydrophobic probe is less efficiently incorporated by the polymer with the BAC sequence as compared to ABC or ACB polymers above the first phase transition temperature. In addition, due to the problem of increasing loss of end group functionality during the subsequent polymerization steps, a novel concept for the one-step synthesis of multi thermoresponsive block copolymers was developed. This allowed to synthesize double thermoresponsive di- and triblock copolymers in a single polymerization step. The copolymerization of different N-substituted maleimides with a thermosensitive styrene derivative (4-vinylbenzyl methoxytetrakis(oxyethylene) ether) led to alternating copolymers with variable LCST. Consequently, an excess of this styrene-based monomer allowed the synthesis of double thermoresponsive tapered block copolymers in a single polymerization step.
Die Selbstorganisation von mehrfach thermisch schaltbaren Blockcopolymeren in verdünnter wässriger Lösung wurde mittels Trübungsphotometer, dynamischer Lichtstreuung, TEM Messungen, NMR sowie Fluoreszenzspektroskopie untersucht. Die schrittweise Überführung eines hydrophilen in ein hydrophobes Blockcopolymer beinhaltet ein oder mehr amphiphile Zwischenstufen mit einstellbarem hydrophilen zu lipophilen Anteil (HLB). Dies führt dazu, dass die Selbstorganisation solcher Polymere in Lösung nicht nur einem Alles-oder-nichts-Prinzip folgt sondern ein mehrstufiges Aggregationsverhalten beobachtet wird. Die Synthese von doppelt thermisch schaltbaren Diblockcopolymeren und dreifach thermisch schaltbaren Triblockcopolymeren wurde durch sequenzielle RAFT Polymerisation realisiert. Dazu wurden zweifach TMS-markierte RAFT Agentien verwendet, welche die Bestimmung der molaren Masse sowie der verbliebenen Endgruppenfunktionalität direkt aus einem Protonen NMR Spektrum erlauben. Mit diesen RAFT Agentien wurde zunächst eine Serie von doppelt thermisch schaltbaren Diblockcopolymeren aus Poly(N-n-propylacrylamid)-b-Poly(N-ethylacrylamid), welche sich lediglich durch die relativen Blocklängen unterscheiden, hergestellt. In Abhängigkeit von der relativen Blocklänge wurde ein unterschiedliches Aggregationsverhalten der Diblockcopolymere in verdünnter wässriger Lösung beobachtet. Des Weiteren wirken die komplementär TMS-markierten Endgruppen als NMR-Sonden während der schrittweisen Aggregation dieser Polymere. Reversible, temperaturabhängige Peakaufspaltung der TMS-Signale in der NMR Spektroskopie spricht für eine Aggregation in gemischte stern-/blumenartige Mizellen, in denen ein Teil der hydrophoben Endgruppen in den hyrophoben Kern zurückfaltet. Obendrein wurden dreifach thermisch schaltbare Triblockcopolymere aus Poly(N-n-propylacrylamid) (A), Poly(methoxydiethylen glycol acrylat) (B) und Poly(N-ethylacrylamid) (C) in allen möglichen Blocksequenzen (ABC, BAC, ACB) durch schrittweisen Aufbau mittels RAFT Polymerisation erhalten. Das Aggregationsverhalten dieser Polymere in verdünnter wässriger Lösung war relativ komplex und hing stark von der Position der einzelnen Blöcke in den Triblockcopolymeren ab. Besonders die Position des Blocks mit der niedrigsten LCST (A) war ausschlaggebend für die resultierenden Aggregate. So wurde oberhalb der ersten Phasenübergangstemperatur nur Aggregation der Triblockcopolymere beobachtet, wenn der A Block an einem der beiden Enden der Polymere lokalisiert war. Wurde der A Block hingegen in der Mitte der Polymere positioniert, entstanden unimere Mizellen zwischen der ersten und zweiten Phasenübergangstemperatur, welche erst aggregierten, nachdem der zweite Block (B) seinen Phasenübergang durchlief. Die Transportereigenschaften dieser Triblockcopolymere wurden mittels Fluoreszenzspektroskopie getestet. Dazu wurde die Einlagerung eines hydrophoben, solvatochromen Fluoreszenzfarbstoffes, Nilrot, in Abhängigkeit der Temperatur untersucht. Im Gegensatz zu den Polymeren mit der Blocksequenz ABC oder ACB, zeigten die Polymere mit der Sequenz BAC eine verminderte Aufnahmefähigkeit des hydrophoben Farbstoffes oberhalb des ersten Phasenübergangs, was auf die fehlende Aggregation und die damit verbundenen relativ kleinen hydrophoben Domänen der unimolekularen Mizellen zwischen der ersten und zweiten Phasenübergangstemperatur zurückzuführen ist. Aufgrund des zunehmenden Verlustes von funktionellen Endgruppen während der RAFT Synthese von Triblockcopolymeren wurde ein neuartiges Konzept zur Einschrittsynthese von mehrfach schaltbaren Blockcopolymeren entwickelt. Dieses erlaubt die Synthese von mehrfach schaltbaren Diblock- und Triblockcopoylmeren in einem einzelnen Reaktionsschritt. Die Copolymeriation von verschiedenen N-substituierten Maleimiden mit einem thermisch schaltbaren Styrolderivat (4-Vinylbenzylmethoxytetrakis(oxyethylene) ether) ergab alternierende Copolymere mit variabler LCST. Die Verwendung eines Überschusses dieses styrolbasierten Monomers erlaubt ferner die Synthese von Gradientenblockcopolymeren in einem einzelnen Polymerisationsschritt.
10

Parras, Petros. "Self-assembly and dynamics in block copolymers with hierarchical order." Thesis, University of Reading, 2006. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.493799.

Повний текст джерела
Стилі APA, Harvard, Vancouver, ISO та ін.
Анотація:
Incorporation of peptide or mesogenic units into block copolymers enables hierarchical order, whereby an interplay between microphase separation and peptide secondary structure formation or liquid crystal ordering occurs. This thesis concerns the self-assembly process and dynamics in block copolymers with hierarchical order. The second and third chapters discuss peptide-based poly(γ-benzyl-Lglutamate)-poly(ethylene glycol)-poly(γ-benzyl-L-glutamate) triblock copolymers and side-group liquid crystal polystyrene-poly [2-(((3-cholesteryl)-oxy)carbonyl)decyl methacrylate)] diblock copolymers. In the first case, the morphology was revealed and the peptide secondary structure was probed by a combination of scattering and microscopy techniques.
Більше джерел

Книги з теми "Self-Assembly of block copolymers":

1

Salvatore, Stefano. Optical Metamaterials by Block Copolymer Self-Assembly. Cham: Springer International Publishing, 2015. http://dx.doi.org/10.1007/978-3-319-05332-5.

Повний текст джерела
Стилі APA, Harvard, Vancouver, ISO та ін.
2

Borisov, Oleg, and Axel H. E. Müller. Self organized nanostructures of amphiphilic block copolymers. Berlin: Springer, 2011.

Знайти повний текст джерела
Стилі APA, Harvard, Vancouver, ISO та ін.
3

Müller, Axel H. E., and Oleg Borisov, eds. Self Organized Nanostructures of Amphiphilic Block Copolymers II. Berlin, Heidelberg: Springer Berlin Heidelberg, 2011. http://dx.doi.org/10.1007/978-3-642-22297-9.

Повний текст джерела
Стилі APA, Harvard, Vancouver, ISO та ін.
4

Müller, Axel H. E., and Oleg Borisov, eds. Self Organized Nanostructures of Amphiphilic Block Copolymers I. Berlin, Heidelberg: Springer Berlin Heidelberg, 2011. http://dx.doi.org/10.1007/978-3-642-22486-7.

Повний текст джерела
Стилі APA, Harvard, Vancouver, ISO та ін.
5

Amphiphilic block copolymers: Self-assembly and applications. Amsterdam: Elsevier, 2000.

Знайти повний текст джерела
Стилі APA, Harvard, Vancouver, ISO та ін.
6

Lindman, B., and P. Alexandridis. Amphiphilic Block Copolymers: Self-Assembly and Applications. Elsevier Science & Technology Books, 2000.

Знайти повний текст джерела
Стилі APA, Harvard, Vancouver, ISO та ін.
7

Massey, Jason. Self-assembly of block copolymers containing poly(ferrocene). Dept of Chemistry, U of Toronto, 2000.

Знайти повний текст джерела
Стилі APA, Harvard, Vancouver, ISO та ін.
8

Block Copolymers with Crystallizable Blocks: Synthesis, Self-Assembly and Applications. MDPI, 2022. http://dx.doi.org/10.3390/books978-3-0365-3325-4.

Повний текст джерела
Стилі APA, Harvard, Vancouver, ISO та ін.
9

Gronheid, Roel, and Paul Nealey. Directed Self-Assembly of Block Co-polymers for Nano-manufacturing. Elsevier Science & Technology, 2015.

Знайти повний текст джерела
Стилі APA, Harvard, Vancouver, ISO та ін.
10

Gronheid, Roel, and Paul Nealey. Directed Self-Assembly of Block Co-polymers for Nano-manufacturing. Elsevier Science & Technology, 2015.

Знайти повний текст джерела
Стилі APA, Harvard, Vancouver, ISO та ін.
Більше джерел

Частини книг з теми "Self-Assembly of block copolymers":

1

Hrub&xFD, Martin, Sergey K. Filippov, and Petr &xt&xBp&xEnek. "Biomedical Application of Block Copolymers." In Macromolecular Self&;#x02010;assembly, 231–50. Hoboken, New Jersey: John Wiley &;#38; Sons, Inc., 2016. http://dx.doi.org/10.1002/9781118887813.ch8.

Повний текст джерела
Стилі APA, Harvard, Vancouver, ISO та ін.
2

Liu, Chi-chun, Kenji Yoshimoto, Juan de Pablo, and Paul Nealey. "Directed Self-Assembly of Block Copolymers." In Microlithography, 767–824. Third edition. | Boca Raton : CRC Press, 2020.: CRC Press, 2020. http://dx.doi.org/10.1201/9781315117171-13.

Повний текст джерела
Стилі APA, Harvard, Vancouver, ISO та ін.
3

Chenkual, Laltanpuii, Dimple S. Lalchandani, Amruta Prabhakar Padakanti, Naveen Chella, and Pawan Kumar Porwal. "Synthesis and Self-Assembly of Block Copolymers." In Block Co-polymeric Nanocarriers: Design, Concept, and Therapeutic Applications, 75–119. Singapore: Springer Nature Singapore, 2023. http://dx.doi.org/10.1007/978-981-99-6917-3_4.

Повний текст джерела
Стилі APA, Harvard, Vancouver, ISO та ін.
4

DeWit, Matthew A., Ali Nazemi, Solmaz Karamdoust, Annelise Beaton, and Elizabeth R. Gillies. "Design, Synthesis and Assembly of Self-Immolative Linear Block Copolymers." In Non-Conventional Functional Block Copolymers, 9–21. Washington, DC: American Chemical Society, 2011. http://dx.doi.org/10.1021/bk-2011-1066.ch002.

Повний текст джерела
Стилі APA, Harvard, Vancouver, ISO та ін.
5

Xie, Ru, Carlos R. López-Barrón, and Norman J. Wagner. "Self-Assembly of Block Copolymers in Ionic Liquids." In ACS Symposium Series, 83–142. Washington, DC: American Chemical Society, 2017. http://dx.doi.org/10.1021/bk-2017-1250.ch005.

Повний текст джерела
Стилі APA, Harvard, Vancouver, ISO та ін.
6

Gowd, E. Bhoje, Mallikarjuna Shroff Rama, and Manfred Stamm. "Nanostructures Based on Self-Assembly of Block Copolymers." In Nanofabrication, 191–216. Vienna: Springer Vienna, 2011. http://dx.doi.org/10.1007/978-3-7091-0424-8_8.

Повний текст джерела
Стилі APA, Harvard, Vancouver, ISO та ін.
7

Whittell, George R., Jessica Gwyther, David A. Rider, and Ian Manners. "Self-Assembly and Applications of Polyferrocenylsilane Block Copolymers." In Complex Macromolecular Architectures, 491–526. Singapore: John Wiley & Sons (Asia) Pte Ltd, 2011. http://dx.doi.org/10.1002/9780470825150.ch16.

Повний текст джерела
Стилі APA, Harvard, Vancouver, ISO та ін.
8

Quémener, D., A. Deratani, and S. Lecommandoux. "Dynamic Assembly of Block-Copolymers." In Constitutional Dynamic Chemistry, 165–92. Berlin, Heidelberg: Springer Berlin Heidelberg, 2011. http://dx.doi.org/10.1007/128_2011_258.

Повний текст джерела
Стилі APA, Harvard, Vancouver, ISO та ін.
9

Karayianni, Maria, and Stergios Pispas. "Self-Assembly of Amphiphilic Block Copolymers in Selective Solvents." In Fluorescence Studies of Polymer Containing Systems, 27–63. Cham: Springer International Publishing, 2016. http://dx.doi.org/10.1007/978-3-319-26788-3_2.

Повний текст джерела
Стилі APA, Harvard, Vancouver, ISO та ін.
10

Wang, Xiaosong, Mitchell A. Winnik, and Ian Manners. "Synthesis, Self-Assembly, and Applications of Polyferrocenylsilane Block Copolymers." In ACS Symposium Series, 274–91. Washington, DC: American Chemical Society, 2006. http://dx.doi.org/10.1021/bk-2006-0928.ch020.

Повний текст джерела
Стилі APA, Harvard, Vancouver, ISO та ін.

Тези доповідей конференцій з теми "Self-Assembly of block copolymers":

1

Nealey, Paul F. "Design of block copolymers for directed self-assembly." In Novel Patterning Technologies 2021, edited by Eric M. Panning and J. Alexander Liddle. SPIE, 2021. http://dx.doi.org/10.1117/12.2584926.

Повний текст джерела
Стилі APA, Harvard, Vancouver, ISO та ін.
2

Angelini, Angelo, Irdi Murataj, Marwan Channab, Eleonora Cara, Natascia De Leo, Candido Fabrizio Pirri, Luca Boarino, and Federico Ferrarese Lupi. "Self-assembly of di-block copolymers for hyperbolic metasurfaces." In CLEO: Applications and Technology. Washington, D.C.: OSA, 2020. http://dx.doi.org/10.1364/cleo_at.2020.jtu2b.25.

Повний текст джерела
Стилі APA, Harvard, Vancouver, ISO та ін.
3

Okabe, Kye, He Yi, Maryann C. Tung, Richard Tiberio, Joost Bekaert, Roel Gronheid, and H. S. P. Wong. "Cross-sectional imaging of directed self-assembly block copolymers." In SPIE Advanced Lithography, edited by Douglas J. Resnick and Christopher Bencher. SPIE, 2015. http://dx.doi.org/10.1117/12.2087569.

Повний текст джерела
Стилі APA, Harvard, Vancouver, ISO та ін.
4

Doerk, Gregory S., Joy Y. Cheng, Charles T. Rettner, Srinivasan Balakrishnan, Noel Arellano, and Daniel P. Sanders. "Deterministically isolated gratings through the directed self-assembly of block copolymers." In SPIE Advanced Lithography, edited by William M. Tong and Douglas J. Resnick. SPIE, 2013. http://dx.doi.org/10.1117/12.2011629.

Повний текст джерела
Стилі APA, Harvard, Vancouver, ISO та ін.
5

Ito, Natsuko, Gregory Blachut, Yusuke Asano, Christopher J. Ellison, Grant C. Willson, Stephen Sirard, XiaoMin Yang, and Austin P. Lane. "Block copolymers for sub-10nm directed self-assembly lithography (Conference Presentation)." In Novel Patterning Technologies 2018, edited by Eric M. Panning and Martha I. Sanchez. SPIE, 2018. http://dx.doi.org/10.1117/12.2297030.

Повний текст джерела
Стилі APA, Harvard, Vancouver, ISO та ін.
6

Azuma, Tsukasa, Yuriko Seino, Hironobu Sato, Yusuke Kasahara, Katsuyoshi Kodera, Ken Miyagi, Masayuki Shiraishi, et al. "Defect dynamics in directed self-assembly of block copolymers (Conference Presentation)." In Advances in Patterning Materials and Processes XXXV, edited by Christoph K. Hohle and Roel Gronheid. SPIE, 2018. http://dx.doi.org/10.1117/12.2297310.

Повний текст джерела
Стилі APA, Harvard, Vancouver, ISO та ін.
7

Azuma, Tsukasa, Yuriko Seino, Hironobu Sato, Yusuke Kasahara, Katsuyoshi Kodera, Phubes Jiravanichsakul, Teruaki Hayakawa, Kenji Yoshimoto, and Mikihito Takenaka. "Nano-defect management in directed self-assembly of block copolymers (Conference Presentation)." In Advances in Patterning Materials and Processes XXXIV, edited by Christoph K. Hohle and Roel Gronheid. SPIE, 2017. http://dx.doi.org/10.1117/12.2257936.

Повний текст джерела
Стилі APA, Harvard, Vancouver, ISO та ін.
8

Sirard, Stephen, Laurent Azarnouche, Emir Gurer, William Durand, Michael Maher, Kazunori Mori, Gregory Blachut, et al. "Interactions between plasma and block copolymers used in directed self-assembly patterning." In SPIE Advanced Lithography, edited by Qinghuang Lin and Sebastian U. Engelmann. SPIE, 2016. http://dx.doi.org/10.1117/12.2220305.

Повний текст джерела
Стилі APA, Harvard, Vancouver, ISO та ін.
9

Ross, C. A., Y. S. Jung, V. P. Chuang, J. G. Son, K. W. Gotrik, R. A. Mickiewicz, J. K. W. Yang, et al. "Templated self-assembly of Si-containing block copolymers for nanoscale device fabrication." In SPIE Advanced Lithography, edited by Daniel J. C. Herr. SPIE, 2010. http://dx.doi.org/10.1117/12.848502.

Повний текст джерела
Стилі APA, Harvard, Vancouver, ISO та ін.
10

Williamson, Lance, Guanyang Lin, Yi Cao, Roel Gronheid, and Paul Nealey. "Tuning the strength of chemical patterns for directed self-assembly of block copolymers." In SPIE Advanced Lithography, edited by Douglas J. Resnick and Christopher Bencher. SPIE, 2014. http://dx.doi.org/10.1117/12.2047585.

Повний текст джерела
Стилі APA, Harvard, Vancouver, ISO та ін.

Звіти організацій з теми "Self-Assembly of block copolymers":

1

Jenekhe, S. A., and X. L. Chen. Self-Assembly of Rod-Coil Block Copolymers. Fort Belvoir, VA: Defense Technical Information Center, August 1999. http://dx.doi.org/10.21236/ada366979.

Повний текст джерела
Стилі APA, Harvard, Vancouver, ISO та ін.
2

Determan, Michael Duane. Synthesis and Characterization of Stimuli Responsive Block Copolymers, Self-Assembly Behavior and Applications. Office of Scientific and Technical Information (OSTI), December 2005. http://dx.doi.org/10.2172/861607.

Повний текст джерела
Стилі APA, Harvard, Vancouver, ISO та ін.
3

Thomas, Edwin L. Tunable PhoXonic Band Gap Materials from Self-Assembly of Block Copolymers and Colloidal Nanocrystals (NBIT Phase II). Fort Belvoir, VA: Defense Technical Information Center, December 2013. http://dx.doi.org/10.21236/ada591353.

Повний текст джерела
Стилі APA, Harvard, Vancouver, ISO та ін.
4

Hiszpanski, Anna M. Directed-Assembly of Block Copolymers for Large-Scale, Three-Dimensional, Optical Metamaterials at Visible Wavelengths. Final LDRD Report. Office of Scientific and Technical Information (OSTI), October 2017. http://dx.doi.org/10.2172/1410019.

Повний текст джерела
Стилі APA, Harvard, Vancouver, ISO та ін.
5

Wu, Sangwook. Theory for dynamical self arrest and gelation in microemulsions and the block copolymer systems. Office of Scientific and Technical Information (OSTI), January 2005. http://dx.doi.org/10.2172/850055.

Повний текст джерела
Стилі APA, Harvard, Vancouver, ISO та ін.
6

Su, Wei-Fangg, L.-Y. Wang, C.-A. Dai, and C.-W. Chen. High Efficiency Photovoltaic Devices Fabricated from Self-Assemble Block Insulating-Conducting Copolymer Containing Semiconducting Nanoparticles. Fort Belvoir, VA: Defense Technical Information Center, December 2005. http://dx.doi.org/10.21236/ada473098.

Повний текст джерела
Стилі APA, Harvard, Vancouver, ISO та ін.
7

Thomas, Edwin. Tunable PhoXonic Band Gap Materials from Self-Assembly of Block Copoliymers and Colloidal Nanocrystals (NBIT Phase II). Fort Belvoir, VA: Defense Technical Information Center, May 2011. http://dx.doi.org/10.21236/ada542359.

Повний текст джерела
Стилі APA, Harvard, Vancouver, ISO та ін.

До бібліографії