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Synthesis And Characterisation Of Block Copolymers Of Polyethylene Oxide Block Styrene Oxide For The Enhancement Of Drug Solubility
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Book Synopsis Synthesis and Characterisation of Block Copolymers of Poly(ethylene Oxide-block-styrene Oxide) for the Enhancement of Drug Solubility by : Michael Edward Donald Crothers
Download or read book Synthesis and Characterisation of Block Copolymers of Poly(ethylene Oxide-block-styrene Oxide) for the Enhancement of Drug Solubility written by Michael Edward Donald Crothers and published by . This book was released on 2003 with total page 211 pages. Available in PDF, EPUB and Kindle. Book excerpt:
Book Synopsis Poly(ethylene Oxide)-block-poly(4-phenylethylstyrene) Diblock Copolymer by : Gloria J. Sheng
Download or read book Poly(ethylene Oxide)-block-poly(4-phenylethylstyrene) Diblock Copolymer written by Gloria J. Sheng and published by . This book was released on 2006 with total page 180 pages. Available in PDF, EPUB and Kindle. Book excerpt:
Book Synopsis Synthesis and Characterisation of Methacrylate-based Water-soluble Diblock and Triblock Copolymers for Drug Dispersion in Aqueous Media by : Giovanni Francesco Unali
Download or read book Synthesis and Characterisation of Methacrylate-based Water-soluble Diblock and Triblock Copolymers for Drug Dispersion in Aqueous Media written by Giovanni Francesco Unali and published by . This book was released on 2000 with total page pages. Available in PDF, EPUB and Kindle. Book excerpt:
Book Synopsis Synthesis and Characterisation of Block Copolymers of Ethylene Oxide and Acrylic Acid by : Andrew Glendinning
Download or read book Synthesis and Characterisation of Block Copolymers of Ethylene Oxide and Acrylic Acid written by Andrew Glendinning and published by . This book was released on 1996 with total page 238 pages. Available in PDF, EPUB and Kindle. Book excerpt:
Book Synopsis Synthesis and Characterization of a Novel Amphiphilic Block Copolymer by : Georgia Mhanna
Download or read book Synthesis and Characterization of a Novel Amphiphilic Block Copolymer written by Georgia Mhanna and published by . This book was released on 2013 with total page 45 pages. Available in PDF, EPUB and Kindle. Book excerpt:
Book Synopsis Synthesis and Characterization of Low Molecular Mass Amphiphilic Block Copolymers and Potential Use in Surfactant Assisted Particle Micro-mixing by : Ekaterini Karakatsanis
Download or read book Synthesis and Characterization of Low Molecular Mass Amphiphilic Block Copolymers and Potential Use in Surfactant Assisted Particle Micro-mixing written by Ekaterini Karakatsanis and published by . This book was released on 2013 with total page pages. Available in PDF, EPUB and Kindle. Book excerpt: In industry the effective mixing and de-agglomeration of two solid particles is vital in applications that require the intimate contact of homogeneously mixed reagents. One such application is in the preparation of pyrotechnic delay elements with reproducible burn speeds. The concept of surfactant assisted particle micro-mixing is proposed. This theory is based in the use of two amphiphilic polymeric surfactants to form two separate stable dispersions of the two solid particles to be mixed, but with the subsequent requirement that the dispersants are able to interact with each other. The formation of the individual dispersions allows for the deagglomeration of the particles and thus their preparation for homogeneous mixing, which is facilitated by the interacting surfactants. Low molecular mass block copolymers of styrene and acrylic acid and poly(ethylene oxide)-poly(propylene oxide) (PEO-PPO) surfactants are the proposed dispersants which will allow for the surfactant interaction by means of hydrogen bonding between the poly(acrylic acid) block and the PEO. The poly(styrene-co-acrylic acid) block copolymer will be synthesised via Atom Transfer Radical Polymerisation (ATRP) and subsequently used in the dispersion experiments. The synthesis of the polystyrene macroinitiators to initiate the block copolymerisation of the t-butyl acrylate was carried out satisfactorily, with good molecular masses and molecular mass distributions. In addition, lH-NMR analysis carried out on the polystyrene macroinitiators confirmed their synthesis. The use of the polystyrene macroinitiators was successful in synthesising poly(styrene-co-t-butyl acrylate) block copolymers with slightly higher polydispersities in comparison to the macroinitiatiators themselves, but acceptable. Hydrolysis of the poly(styrene-co-t-butyl acrylate) block copolymer to poly(styrene-co-acrylic acid) was successful in the presence of trifluoroacetic acid as catalyst. Attempts to hydrolyse in basic conditions (NaOH) and alternatively in acidic conditions (HCI) were not successful. Use of the poly(styrene-co-acrylic acid) amphiphilic block copolymer to emulsion polymerise styrene requires the ionised form of the polymer and was therefore not favourable to observe surfactant-surfactant hydrogen bonding. In addition, attempts to synthesise a wax emulsion stabilised by a PEO containing surfactant proved to be unsuccessful. Subsequently, the micro-mixing experiments were carried out by using a poly(acrylic acid) stabilised melamine dispersion and a commercially available PEO containing surfactant stabilised wax emulsion. The interaction between the melamine and the poly(acrylic acid) allows for the formation of a stable melamine dispersion at above 7% poly(acrylic acid) : melamine ratio (mass basis). Analysis by SEM shows that without the poly(acrylic acid) dispersant no wax particles are found to occur on the melamine particle surface. However, in an attempt to determine whether the amount of wax interaction increases with poly(acrylic acid) content, it was found that in the absence of poly(acrylic acid) dispersant, the most amount of wax precipitated out with the melamine. This is possibly attributable to the preferential occlusion of the wax particles between the melamine particles rather than surface attachment. Introduction of the poly(acrylic acid), however, shows via SEM analysis that the hydrogen bond interaction between the acrylic acid group and the ethylene oxide group does occur, since the attachment of the wax particles on the melamine particle surface is observed. Although results show that the surfactant-surfactant interaction allows for the micro mixing of particles, some refinement is required with respect to the systems that this phenomenon can be applied to. In addition, factors such as particle type, particle size and surfactant type will influence the micro-mixing interaction. It is therefore recommended that these factors be investigated in order to completely identify the micro-mixing phenomenon.
Book Synopsis Synthesis and Characterisation of Tapered Statistical Block Copolymers and Their Influence on the Solubility and Dissolution Characteristics of Hydrophobic Drugs by : Martin James Quinn
Download or read book Synthesis and Characterisation of Tapered Statistical Block Copolymers and Their Influence on the Solubility and Dissolution Characteristics of Hydrophobic Drugs written by Martin James Quinn and published by . This book was released on 2001 with total page 237 pages. Available in PDF, EPUB and Kindle. Book excerpt:
Book Synopsis Synthesis and Applications of Copolymers by : Anbanandam Parthiban
Download or read book Synthesis and Applications of Copolymers written by Anbanandam Parthiban and published by John Wiley & Sons. This book was released on 2014-06-23 with total page 408 pages. Available in PDF, EPUB and Kindle. Book excerpt: Understanding the reactivity of monomers is crucial in creating copolymers and determining the outcome of copolymerization. Covering the fundamental aspects of polymerization, Synthesis and Applications of Copolymers explores the reactivity of monomers and reaction conditions that ensure that the newly formed polymeric materials exhibit desired properties. Referencing a wide-range of disciplines, the book provides researchers, students, and scientists with the preparation of a diverse variety of copolymers and their recent developments, with a particular focus on copolymerization, crystallization, and techniques like nanoimprinting and micropatterning.
Book Synopsis Synthesis and Characterisation of Block Copolymers of Methylene and Poly(oxyethylene) for Use in Drug Delivery Systems by : Mahmoud Ameri
Download or read book Synthesis and Characterisation of Block Copolymers of Methylene and Poly(oxyethylene) for Use in Drug Delivery Systems written by Mahmoud Ameri and published by . This book was released on 1998 with total page 233 pages. Available in PDF, EPUB and Kindle. Book excerpt:
Book Synopsis Synthesis and Characterization of Smart Block Copolymers for Biomineralization and Biomedical Applications by :
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 Nanomaterial written by David G. Capco and published by Springer Science & Business Media. This book was released on 2014-03-28 with total page 284 pages. Available in PDF, EPUB and Kindle. Book excerpt: The rapidly developing field of nanomaterials has expanded in many commercial areas. More recent studies have begun to provide a foundation for understanding how nanomaterials influence cells and how they also can serve as methodological tools for studies in medicine and cell biology, including research into stem cells. Recent investigations have shown affects of nanomaterials on specific subcellular structures, such as the actin-based brush border network in cells with an increasing emphasis on the barrier function of epithelial tissues. While other studies have shown involvement of nanoparticles in specific cytoplasmic signal transduction events such as the rise in intracellular free calcium, a signaling event known to regulate many changes in cell architecture and function. In parallel, nanomaterials are increasingly used in medicine for drug delivery, treatment of cancer and an increasing number of new applications. This book investigates these areas and also includes new methods for assessment in cell biology and medicine.
Book Synopsis Synthesis and Characterization of Block Copolymers of Poly(N-acyl Ethyleneimines) and Poly(ethylene Glycol) by : A. Xavier Swamikannu
Download or read book Synthesis and Characterization of Block Copolymers of Poly(N-acyl Ethyleneimines) and Poly(ethylene Glycol) written by A. Xavier Swamikannu and published by . This book was released on 1984 with total page 436 pages. Available in PDF, EPUB and Kindle. Book excerpt:
Book Synopsis Synthesis of Polyanhydrides for Controlled Drug Delivery by : Brandon Michael Vogel
Download or read book Synthesis of Polyanhydrides for Controlled Drug Delivery written by Brandon Michael Vogel and published by . This book was released on 2003 with total page 220 pages. Available in PDF, EPUB and Kindle. Book excerpt: This thesis is divided into three sections, all related to polyanhydride synthesis: first, attempts at the synthesis of polyanhydride-polyanhydride block copolymers, second, synthesis and characterization of polyethylene glycol containing aromatic polyanhydrides, and third, microwave polymerization of polyanhydrides. A strategy was developed to produce block copolymers of polyanhydrides using a hydroxyamide linker for the controlled release of proteins and higher molecular weight drugs. Block copolymers offer more control over micro structure than random copolymers, which allows for improved controlled release of proteins. The condensation polymerization of anhydrides typically yields random copolymers, therefore making the synthesis of block copolymers difficult. Methods of block copolymer synthesis explored consisted of end-functionalizing a short polyanhydride chain with hydroxylamine and ring opening polymerization through a macro-initiator. A discussion of the various methods explored is presented. Adding ethylene glycol segments to the monomers allows one to tailor the hydrophobicity of the polyanhydride, which in turn dictates the solubility of molecules within the polymer matrix and degradation rate of the polymer. Aromatic diacids were synthesized from chlorinated triethylene and pentaethylene glycols and hydroxy benzoic acid. The diacids were acetylated with acetic anhydride to produce homopolymers of polyanhydrides for the stabilization of proteins and drugs. The glycol containing polyanhydrides were characterized by NMR, GPC, DSC and dissolution testing. The release characteristics of the new polyanhydrides were evaluated with a hydrophilic (Acid Orange) and hydrophobic dye (Rhodamine B Base) and the release mechanisms were investigated. Microwave radiation was used to explore the high throughput synthesis of polyanhydrides for materials library characterization. Aliphatic diacids were acetylated in situ for two minutes in a closed reaction vessel before removal of excess acetic anhydride and subsequent polymerization, all in the microwave. Reaction conditions such as acetic anhydride equivalents, duration of microwave exposure and comparison to conventional polycondensation were explored. Microwave polymerization times of 6 to 8 minutes yielded optimum number average molecular weights in contrast to conventional polycondensation, which took between 1.5 to 2 hours under high vacuum. In conclusion, this thesis explored the synthesis and characterization of various polyanhydride-based homopolymers and copolymers by conventional as well as microwave techniques for controlled drug delivery applications.
Book Synopsis Manipulating the Morphologies of Poly(vinyl Alcohol) Block Copolymer Surfactants by :
Download or read book Manipulating the Morphologies of Poly(vinyl Alcohol) Block Copolymer Surfactants written by and published by . This book was released on 2014 with total page 239 pages. Available in PDF, EPUB and Kindle. Book excerpt: Amphiphilic block copolymers (ABCs) are macromolecules containing well-defined hydrophilic and hydrophobic segments that self-assemble into nanoscale aggregates such as spherical and cylindrical micelles and vesicles, when dispersed in block-selective solvents. ABCs possess a miniscule critical micelle concentration, which results in kinetically trapped and persistent assemblies in solution with slow chain exchange between aggregates. This makes them useful as rheological modifiers for personal care products, enhanced oil recovery, and drug delivery formulations. Their utility in many of these applications is crucially dependent on the ability to control the micellar morphologies that they adopt in selective solvents. Triggering ABC micellar morphological transformations, i.e. from spherical to cylindrical micelles, is important for generating "on-demand" stimuli-responsive morphologies that control the aggregate morphology and the bulk solution properties in any given application. In this thesis, we develop the straightforward synthesis of biodegradable and biocompatible ABCs comprised of poly(vinyl acetate) (PVAc) and poly(vinyl alcohol) (PVA), with narrow molecular distributions and variable yet well-defined compositions. These block copolymer amphiphiles readily form spherical micelles in aqueous dispersions. We demonstrate that the addition of a water-soluble poly(ethylene oxide) (PEO) homopolymer to these dispersions results in a rapid transformation of these spherical micelles into cylindrical micelles. Dilution of these cylindrical micelles with water induces their reversion to spherical micelles. Our results indicate that the reversible morphology change depends sensitively on the PEO homopolymer concentration and molecular weight, as well as the length of the PVA corona block of the micelles. Through a series of quantitative 1H NMR studies, we found that the preferential partitioning of PEO homopolymer into the PVAc micellar core drives this morphological transformation. We also investigated the aqueous micellar self-assembly of non-covalent amphiphilic block copolymers (NC-ABCs) derived from complexation of an anionic gemini dicarboxylate surfactant (Na-96) to poly(ethylene oxide)-block-poly(2-(methacryloyloxy)-ethyltrimethylammonium chloride) (mPEO-b-qPDMAEMAxCl) (x = 48 or 110) at charge stoichiometries of [qDMAEMA+]:[COO-] = 1:1 and 1:0.5. Our results demonstrate that these polymer/surfactant complexes adopt rod-like conformations, the liquid crystallinity of which drives the formation of facetted vesicles and hollow tubular micelles.
Book Synopsis Controlled Anionic Synthesis of Poly(styrene-block-ethylene Oxide) Copolymers with Fluorescent Labeling by : Moonseok Chun
Download or read book Controlled Anionic Synthesis of Poly(styrene-block-ethylene Oxide) Copolymers with Fluorescent Labeling written by Moonseok Chun and published by . This book was released on 1995 with total page 262 pages. Available in PDF, EPUB and Kindle. Book excerpt:
Book Synopsis The Synthesis and Characterisation of Oil Soluble Block Copolymers by : Christine Mary Fernyhough
Download or read book The Synthesis and Characterisation of Oil Soluble Block Copolymers written by Christine Mary Fernyhough and published by . This book was released on 1998 with total page pages. Available in PDF, EPUB and Kindle. Book excerpt:
Book Synopsis Synthesis and Characterisation of Poly (methylphenylsilane) Block Copolymers by : Nicholas Agostino Antonio Rossi Rossi
Download or read book Synthesis and Characterisation of Poly (methylphenylsilane) Block Copolymers written by Nicholas Agostino Antonio Rossi Rossi and published by . This book was released on 2003 with total page 0 pages. Available in PDF, EPUB and Kindle. Book excerpt:
