Download or read book Synthesis and Characterization of Smart Block Copolymers for Biomineralization and Biomedical Applications written by Mathumai Kanapathipillai and published by . This book was released on 2008 with total page pages. Available in PDF, EPUB and Kindle. Book excerpt:

Download or read book Synthesis and Characterization of Smart Block Copolymers for Biomineralization and Biomedical Applications written by and published by . This book was released on 2008 with total page pages. Available in PDF, EPUB and Kindle. Book excerpt: Self-assembly is a powerful tool in forming structures with nanoscale dimensions. Self-assembly of macromolecules provides an efficient and rapid pathway for the formation of structures from the nanometer to micrometer range that are difficult, if not impossible to obtain by conventional lithographic techniques [1]. Depending on the morphologies obtained (size, shape, periodicity, etc.) these self-assembled systems have already been applied or shown to be useful for a number of applications in nanotechnology [2], biomineralization [3, 4], drug delivery [5, 6] and gene therapy [7]. In this respect, amphiphilic block copolymers that self-organize in solution have been found to be very versatile [1]. In recent years, polymer-micellar systems have been designed that are adaptable to their environment and able to respond in a controlled manner to external stimuli. In short, synthesis of 'nanoscale objects' that exhibit 'stimulus-responsive' properties is a topic gathering momentum, because their behavior is reminiscent of that exhibited by proteins [8]. By integrating environmentally sensitive homopolymers into amphiphilic block copolymers, smart block copolymers with self assembled supramolecular structures that exhibit stimuli or environmentally responsive properties can be obtained [1]. Several synthetic polymers are known to have environmentally responsive properties. Changes in the physical, chemical or biochemical environment of these polymers results in modulation of the solubility or chain conformation of the polymer [9]. There are many common schemes of engineering stimuli responsive properties into materials [8, 9]. Polymers exhibiting lower critical solution temperature (LCST) are soluble in solvent below a specific temperature and phase separate from solvent above that temperature while polymers exhibiting upper critical solution temperatures (UCST) phase separate below a certain temperature. The solubility of polymers with ionizable moieties depends on the pH of the solution. Polymers with polyzwitterions, anions and cations have been shown to exhibit pH responsive self assembly. Other stimuli responsive polymers include glucose sensitive polymers, calcium ion-sensitive polymers and so on. Progress in living radical polymerization (LRP) methods [10] has made it possible for the facile synthesis of these block copolymer systems with controlled molecular weights and well defined architectures. The overall theme of this work is to develop novel smart block copolymers for biomineralization and biomedical applications. Synthesis and characterization of self-assembling thermoreversible ionic block copolymers as templates in biomimetic nanocomposite synthesis using a bottom-up approach is a novel contribution in this respect. Further, we have extended these families of copolymers to include block copolymer-peptide conjugates to enhance biological specificity. Future directions on this work will focus on enhancing the polymer templating properties for biomineralization by expanding the family of block copolymers with organic polypeptides and biological polypeptide scaffolds as well as a detailed understanding of the polymer-inorganic nanocomposites at the molecular level using small angle scattering analysis. Glucose responsive polymer hydrogels for drug delivery, polymer-ligand conjugates for non-viral therapy and thermoresponsive injectable photocrosslinkable hydrogels for posttraumatic arthritis cartilage healing are other applications of these novel copolymers synthesized in our work.

Download or read book Block Copolymers in Nanoscience written by Massimo Lazzari and published by Wiley-VCH. This book was released on 2007-06-27 with total page 447 pages. Available in PDF, EPUB and Kindle. Book excerpt: This first book to take a detailed look at one of the key focal points where nanotechnology and polymers meet provides both an introductory view for beginners as well as in-depth knowledge for specialists in the various research areas involved. It investigates all types of application for block copolymers: as tools for fabricating other nanomaterials, as structural components in hybrid materials and nanocomposites, and as functional materials. The multidisciplinary approach covers all stages from chemical synthesis and characterization, presenting applications from physics and chemistry to biology and medicine, such as micro- and nanolithography, membranes, optical labeling, drug delivery, as well as sensory and analytical uses.

Download or read book Block Copolymers written by Francisco Balta Calleja and published by CRC Press. This book was released on 2000-06-09 with total page 604 pages. Available in PDF, EPUB and Kindle. Book excerpt: A summary of block copolymer chemical structures and synthesis. It discusses physical methods of characterization such as computer simulation, microhardness, dielectric spectroscopy, thermal mechanical relaxation, ultrasonic characterization, transmission electron microscopy, X-ray scattering, and NMR, among others. It also outlines rheological and processing parameters in the multiphase polymer systems with stable microstructures.

Download or read book Synthesis and Characterization of Stimuli Responsive Block Copolymers Self assembly Behavior and Applications written by Michael Duane Determan and published by . This book was released on 2006 with total page 296 pages. Available in PDF, EPUB and Kindle. Book excerpt: Water-soluble stimuli responsive block copolymers are a rapidly emerging class of materials with great potential in biomedical and technological applications. In this work a novel class of pentablock copolymers are synthesized via atom transfer radical polymerization techniques and their stimuli-responsive self-assembly properties are characterized. Aqueous solutions of these materials are observed to form micelles and hydrogels in response to changes in both temperature and pH. Cryogenic transmission electron microscopy (cryo-TEM) and small angle neutron and X-ray scattering (SANS and SAXS) techniques are used to investigate the nanoscale structures formed by these pentablock copolymers in solution. The gel structure and mechanical properties are investigated with SANS and rheological techniques. The multi-responsive properties of these materials are utilized to formulate a stimuli responsive drug delivery formulation that exhibits thermoreversible gelation and pH dependent release rate of model drugs.

Download or read book Synthesis and Characterization of Absorbable Block Copolymers for Vascular Applications written by Kory Patrick Hamel and published by . This book was released on 1999 with total page 144 pages. Available in PDF, EPUB and Kindle. Book excerpt:

Download or read book Synthesis and Characterization of Modified Block Copolymers written by Chi-Fung Chu and published by . This book was released on 1988 with total page 412 pages. Available in PDF, EPUB and Kindle. Book excerpt:

Download or read book Synthesis and Characterization of Stimuli Responsive Block Copolymers Self Assembly Behavior and Applications written by and published by . This book was released on 2005 with total page 152 pages. Available in PDF, EPUB and Kindle. Book excerpt: The central theme of this thesis work is to develop new block copolymer materials for biomedical applications. While there are many reports of stimuli-responsive amphiphilic [19-21] and crosslinked hydrogel materials [22], the development of an in situ gel forming, pH responsive pentablock copolymer is a novel contribution to the field, Figure 1.1 is a sketch of an ABCBA pentablock copolymer. The A blocks are cationic tertiary amine methacrylates blocked to a central Pluronic F127 triblock copolymer. In addition to the prerequisite synthetic and macromolecular characterization of these new materials, the self-assembled supramolecular structures formed by the pentablock were experimentally evaluated. This synthesis and characterization process serves to elucidate the important structure property relationships of these novel materials, The pH and temperature responsive behavior of the pentablock copolymer were explored especially with consideration towards injectable drug delivery applications. Future synthesis work will focus on enhancing and tuning the cell specific targeting of DNA/pentablock copolymer polyplexes. The specific goals of this research are: (1) Develop a synthetic route for gel forming pentablock block copolymers with pH and temperature sensitive properties. Synthesis of these novel copolymers is accomplished with ATRP, yielding low polydispersity and control of the block copolymer architecture. Well defined macromolecular characteristics are required to tailor the phase behavior of these materials. (2) Characterize relationship between the size and shape of pentablock copolymer micelles and gel structure and the pH and temperature of the copolymer solutions with SAXS, SANS and CryoTEM. (3) Evaluate the temperature and pH induced phase separation and macroscopic self-assembly phenomenon of the pentablock copolymer. (4) Utilize the knowledge gained from first three goals to design and formulate drug delivery formulations based on the multi-responsive properties of the pentablock copolymer. Demonstrate potential biomedical applications of these materials with in vitro drug release studies from pentablock copolymer hydrogels. The intent of this work is to contribute to the knowledge necessary for further tailoring of these, and other functional block copolymer materials for biomedical applications.

Download or read book Synthesis and Characterization of Photocleavable Polymers and Block Copolymers written by Hui Zhao and published by . This book was released on 2013 with total page 0 pages. Available in PDF, EPUB and Kindle. Book excerpt:

Download or read book Synthesis and Characterization of Polymandelide and Lactide methacrylate Block Copolymers written by Tianqi Liu and published by . This book was released on 2002 with total page 416 pages. Available in PDF, EPUB and Kindle. Book excerpt:

Download or read book Commencement written by Iowa State University and published by . This book was released on 2008 with total page 492 pages. Available in PDF, EPUB and Kindle. Book excerpt:

Download or read book Preparation of Functional Polymers and Block Copolymers Via Post polymerization Modifications for Biomedical Applications written by Carsten Rössel and published by . This book was released on 2021* with total page pages. Available in PDF, EPUB and Kindle. Book excerpt: The research in this thesis focuses predominately on the preparation and characterization of polymers and block copolymers containing ionizable or charged moieties. In the first part of this thesis, the synthesis and polymerization of various monomers is described, which are converted into polyelectrolytes and polyampholytes with a high charge density later on. Such functional materials are highly versatile, finding use as surfactants, in heterogeneous catalysis, or in biomedical applications. In the second part of this thesis, polyether-based block copolymers are prepared by anionic ring-opening polymerization for use in gene and drug delivery.

Download or read book Synthesis and Characterization of PDMS based Block Copolymers Toward Sub 10nm Nanopatterning written by Yingdong Luo and published by . This book was released on 2015 with total page 183 pages. Available in PDF, EPUB and Kindle. Book excerpt: Block copolymer self-assembly has been used as nanopatterning towards applications of lithography for decades. For the purpose of smaller, faster and cheaper transistor developments, block copolymers with high Flory-Huggins parameter and better etching contrast need to be further developed. PDMS based block copolymers are of the most interest among all candidates. I synthesized a library of well defined PDMS-b-PMMA, PDMS-b-PS and PDMS-b-PEO through "click" chemistry. The Flory-Huggins interaction parameters of these block copolymers are characterized much higher than conventional block copolymers as expected. Therefore, sub-10 nm domain periods are achieved by these materials in bulk. Significantly, long range ordered nanoline and nanodot patterns have been produced by PDMS-b-PMMA. Furthermore, a small molecule (L)-tartaric acid used as a hydrogen bonding donor was proved to efficiently suppress the crystallinity of PEO and significantly enhance the self-assembly behavior. Finally, the triazole moiety in the middle of the block copolymer which synthesized by "click" chemistry was functionalized to produce an ionic junction block copolymer. The electrostatic interactions before the opposite charges act as an extra enthalpy to help the self-assembly. Therefore, order disorder transition temperature of the block copolymer was dramatically increased.

Download or read book Block Copolymer Templated Nitrogen enriched Nanocarbons written by Mingjiang Zhong and published by . This book was released on 2013 with total page 315 pages. Available in PDF, EPUB and Kindle. Book excerpt: "Reversible-deactivation radical polymerization (RDRP), also referred to as controlled/"living" radical polymerization (CRP) has been developed over the past 20 years. RDRP promotes the synthesis of well-defined polymeric materials with controlled molecular weights and molecular weight distributions, complex topologies and functionalities. In the past decade, the Matyjaszewski and Kowalewski groups pioneered the work of synthesizing nanostructured carbon by pyrolysis of polyacrylonitrile (PAN) containing polymeric precursors prepared via RDRP. My contribution to this topic was primarily focused on the following aspects: (1) optimization of the synthetic procedure, (2) deeper investigation of the structures, (3) exploration of the surface chemistry with particular emphasis of nitrogen functionality, (4) and energy related applications. This thesis first focuses on addressing current challenges in RDRP particularly in atom transfer radical polymerization (ATRP), one of the most robust RDRP techniques. Based on the development of a deep mechanistic understanding of RDRP's, ATRP was then used for the synthesis of PAN containing block copolymers followed by applying a series of analytical tools to provide detailed physical characterization. Finally, these materials were utilized as precursors for the formation of nanocarbons that were evaluated in various energy related applications. The development of nanostructured carbon materials from PAN precursors is discussed in Chapter 1. Particular emphasis is placed on the rational structural design of PAN containing polymeric precursors developed in the Matyjaszewski and Kowalewski groups, while the detailed synthetic methodology will be discussed in the subsequent chapters. Controlled synthesis is the prerequisite for many applications. The successful preparation of block copolymers via RDRP requires preparation of a macroinitiator with preserved chain end functionality (CEF). Work described in Chapter 2 resulted in the establishment of a universal rule for quantifying the CEF in all RDRPs, which is also the most important criterion for determining the "livingness" and degree of control over the polymerization. The parameters affecting the level of CEF preservation are determined. Another challenge in ATRP is diminishing the concentration of catalyst employed during the polymerization procedure in order to reduce the cost and simplify the purification steps. Chapter 3 describes the systematic study of RDRP in the presence of zerovalent copper, which offers significant advantages in this regard. The contribution of all of the potential reactions occurring in an ATRP carried out in the presence of copper zero were evaluated, and a supplemental activator and reducing agent (SARA) ATRP mechanism is concluded to precisely describe this system. How to conduct and optimize SARA ATRP system is then demonstrated. Chapter 4 is focused on another aspect of the robust capability of ATRP : controlling the molecular weight distribution. Activator regeneration electron transfer (ARGET) ATRP was employed to prepare polystyrene-block-poly(methyl acrylate) copolymers with tunable dispersity in the range of 1.32 to 2.0 for each block. Knowledge attained from the studies discussed in Chapter 2 to 4 has been extensively utilized in the studies of nanocarbons. Chapter 5 discusses the preparation of a series of PAN containing diblock copolymers that were used as precursors for the preparation of nanocarbons. The block copolymers undergo phase separation and then the poly(n-butyl acrylate) serves as a sacrificial segment upon pyrolysis. Both thin film and bulk nanocarbons with diverse morphologies, resembling the original phase-separated copolymer precursors, were prepared. The carbonization of bulk copolymer precursors with branched PAN domains was of particular interest; which resulted in the formation of porous nanocarbons with large surface area and highly accessible nitrogen functionality originating from PAN. Chapter 6 illustrates how porosity and accessible nitrogen functionality in the nanocarbon introduced in Chapter 5 can be utilized for CO2 capture. The main emphasis was placed on the surface area and nitrogen content's influence on adsorption capacity and selectivity was studied. Chapter 7 discusses the application of PAN-derived nanocarbons as electrode materials for supercapacitors. Materials displaying both high energy density and high power density were achieved. This excellent performance was partially due to the mesoporous structure with high specific surface area, in combination with the pseudocapacitance originating from graphitic edge nitrogens. Evidence of electrochemical activity of the nitrogen heteroatoms provided the motivation to explore the performance of copolymer templated nanocarbon as an electrocatalyst for oxygen reduction, as described in Chapter 8. A desirable 4-electron transfer process with a low overpotential system was achieved by as-prepared nanocarbon film with porous morphology; which again, demonstrates one of the unique properties of nanocarbons prepared from PAN containing block copolymer precursors. Finally, a summary is provided in Chapter 9 and some future directions regarding synthesis and utility of heteroatom-enriched nanocarbons are discussed."--Pages ii-v.

Download or read book Synthesis and Characterization of Temperature and Light responsive Polymers and Block Copolymers written by Florian D. Jochum and published by . This book was released on 2010 with total page 123 pages. Available in PDF, EPUB and Kindle. Book excerpt:

Download or read book Synthesis and Characterization of Polymeric and Inorganic Materials for Biomedical Applications written by Georgina Annette Comiskey and published by . This book was released on 2013 with total page 164 pages. Available in PDF, EPUB and Kindle. Book excerpt:

Download or read book Synthesis and Characterization of Amphiphilic Block Copolymers Based on Polyisobutylene written by Yuji Hongu and published by . This book was released on 1985 with total page 436 pages. Available in PDF, EPUB and Kindle. Book excerpt: