Download or read book Synthesis of Sequence Defined Degradable Polymers Through Ring Opening Polymerization written by Shijie Deng and published by . This book was released on 2023 with total page 0 pages. Available in PDF, EPUB and Kindle. Book excerpt: Ring-opening polymerization is an essential form of chain-growth polymerization that facilitates precise control over the polymerization process. Our research delved into the realm of redox- switchable catalysis and its application in synthesizing polyesters, ethers, and carbonates through ring-opening polymerization. To broaden the range of available monomers, we also explored the ring-opening polymerization of aromatic N-carboxyanhydrides with six-membered rings, resulting in the creation of aromatic polyamides. Leveraging the potential of biodegradable polymers crafted from ring-opening polymerizations, we investigated how the stereocomplexation of block copolymers could enhance the shear viscosities of the polymer solutions in brine.
Download or read book Sequence Controlled Polymers written by Jean-François Lutz and published by John Wiley & Sons. This book was released on 2018-04-09 with total page 532 pages. Available in PDF, EPUB and Kindle. Book excerpt: Edited by a leading authority in the field, the first book on this important and emerging topic provides an overview of the latest trends in sequence-controlled polymers. Following a brief introduction, the book goes on to discuss various synthetic approaches to sequence-controlled polymers, including template polymerization, genetic engineering and solid-phase chemistry. Moreover, monomer sequence regulation in classical polymerization techniques such as step-growth polymerization, living ionic polymerizations and controlled radical polymerizations are explained, before concluding with a look at the future for sequence-controlled polymers. With its unique coverage of this interdisciplinary field, the text will prove invaluable to polymer and environmental chemists, as well as biochemists and bioengineers.
Download or read book Design and Synthesis of Monomers Toward Sequence Controlled Polymers written by Margaret Gerthoffer and published by . This book was released on 2023 with total page 0 pages. Available in PDF, EPUB and Kindle. Book excerpt: Strategies to synthesize sequence-defined polymers remain limited for industrial-scale applications, often due to time consuming iterative addition or polymerization methods possessing low functional group tolerances. Throughout my PhD, I have utilized both ring-opening metathesis polymerization (ROMP) and pressure-induced polymerization to form sequence-defined polymers from deliberately designed A-B monomers. ROMP of electronically-biased paracyclophanedienes (pCpd) can form donor-acceptor poly(arylenevinylene)s. In addition, the pressure-induced polymerization of engineered aryl/perfluoroaryl (Ar/ArF) co-crystals translates into sequence-specific sp3-saturated copolymers known as nanothreads. Both polymerization methods form sequence-specific copolymers as dictated by the supramolecular monomer design. The ROMP of ring-strained pCpds containing dialkyloxybenzene donor and benzothiadiazole acceptor obtains well-defined polymers with ruthenium-based initiators. This design promotes favors sequence specificity between the electronically-activated dialkyloxybenzene and electronically-deficient benzothiadiazole that can guide the initiator homogenously during ring opening and polymerization events. During my PhD, I have discovered that the presence of sterically asymmetric alkyloxy groups (methoxy and octyloxy) on the donor further guides the polymerization process. I have elucidated that the steric effects of the alkyloxy donor group can further control the rate of well-defined donor-acceptor copolymer synthesis due to supramolecular interactions with ruthenium-based initiators. To expand on this, I targeted the synthesis of various alkyloxybenzene donor groups in both linear and branched substitutions to compare ROMP rate and polymer sequence definition with benzothiadiazole acceptors. The investigated pCpds formed well-defined polymers that did not prohibit ruthenium-catalyst attachment as confirmed by GPC and NMR spectroscopy. I have moreover been able to synthesize ladderane-like polymers known as nanothreads by the pressure-induced polymerization (23+ GPa) of alternating eclipsed stacks of aromatic cores in solid-state Ar/ArF co-crystals. I have designed monomer pairs through preorganization of Ar/ArF synthons with varied quadrupole, hydrogen, and halogen bonding to understand the design elements necessary to form substituted nanothreads at reduced pressure thresholds. For all co-crystals, supramolecular engineering has reduced polymerization pressures compared to individual components as confirmed through in situ Raman, NMR, and XRD spectroscopies under pressure. Phenol:pentafluorophenol illustrates strong hydrogen bonding that stabilizes interstack interactions under pressure to form nanothreads. However, I discovered that hydrogen bonding amongst external functionalities can prohibit facile compressibility if the direction aligns to the putative Ar/ArF thread axis. Direct intrastack hydrogen bonding can in fact increase the required pressure of polymerization (30 GPa+). Designing appropriate hydrogen bonding scaffolds in Ar/ArF co-crystals thus offers the ability to target sequence-controlled nanothread production at a reduced pressure.
Download or read book Ring Opening Metathesis Polymerisation and Related Chemistry written by Ezat Khosravi and published by Springer Science & Business Media. This book was released on 2002-03-31 with total page 524 pages. Available in PDF, EPUB and Kindle. Book excerpt: Proceedings of the NATO Advanced Study Institute, held in Polaica-Zdroj, Poland, 3-15 September 2000
Download or read book Synthesis of Functional Degradable Polymers by Radical Ring opening Polymerization written by and published by . This book was released on 2012 with total page 44 pages. Available in PDF, EPUB and Kindle. Book excerpt:
Download or read book Ring opening Metathesis Polymerization of Substituted Cyclopropenes written by Benjamin Ross Elling and published by . This book was released on 2018 with total page pages. Available in PDF, EPUB and Kindle. Book excerpt: Life would not be possible without precise macromolecular sequence control. The ability of biological systems to encode information, transmit instructions, and catalyze chemical reactions relies on the proper ordering of monomeric units. While our synthetic capabilities may trail those nature has developed through billions of years of evolution, continued advances in polymer science have allowed ever greater control over polymer microstructures. Specifically, living polymerization techniques, such as ring-opening metathesis polymerization (ROMP), have given us the tools to synthesize polymers with defined molecular weights and narrow molecular weight distributions. While ROMP is typically driven by the release of ring strain, surprisingly little research has been performed on the polymerization of cyclopropenes (CPEs), the monocyclic olefin with the highest ring strain. We believed that the high strain energy of this class of monomers along with the ability to tune the steric environment through strategic substitutions would result in unique reactivity and potential to control monomer sequences. In building a library of CPEs capable of ROMP, we discovered a unique class of CPEs that only singly added to Grubbs third generation catalyst followed by no further homopolymerization. We have used this behavior to develop a system for perfectly alternating ROMP with CPEs and low-strain cyclic olefins. Further investigations have shown that this technique can be extended to incorporate other low-strain cycles, allowing for functionalities to be directly incorporated into the polymer backbone. Additionally, with these molecules in hand, we have been able to incorporate single functional units into a polymer backbone by addition of precisely one equivalent of monomer relative to catalyst. At first using this technique to synthesize telechelic polymers, we have successfully optimized this system to allow the incorporation of exactly one monomer into a ROMP polymer at any defined location along the backbone, giving unprecedented control over polymer sequence using via solution chemistry.
Download or read book Synthesis of Sequence defined Oligomers and Polymers written by Nadja Franz and published by . This book was released on 2009 with total page 174 pages. Available in PDF, EPUB and Kindle. Book excerpt:
Download or read book Ring opening Polymerization of beta substituted beta propiolactones written by Yan Zhang and published by . This book was released on 1990 with total page 340 pages. Available in PDF, EPUB and Kindle. Book excerpt:
Download or read book Ring opening Metathesis Polymerization of Cyclopropenes and Ladderenes written by Jessica Kalay Su and published by . This book was released on 2020 with total page pages. Available in PDF, EPUB and Kindle. Book excerpt: The importance of polymer microstructure is manifested in nature, where the precisely regulated monomer sequence in biomacromolecules enables their controlled folding and assembly to afford vital biological functions. In the pursuit of man-made materials with sophisticated properties, the field of polymer chemistry has developed rapidly to enable the synthesis of polymers with controlled microstructures. Specifically, living polymerization techniques, such as ring-opening metathesis polymerization (ROMP), enable excellent control over polymer molecular weight, composition, and architecture. ROMP is driven primarily by the release of ring strain in cyclic olefin monomers, but surprisingly few studies have been performed on the ROMP of cyclopropenes (CPEs), the most strained monocyclic olefins. In 2015, our group discovered that a class of 1,1-disubstituted CPE undergoes selective single addition to Grubbs third generation catalyst. Monomers which undergo single addition are extremely rare for chain-growth polymerizations and are particularly useful for manipulating the monomer sequence in a polymer. As such, we focused our research efforts on discovering other CPEs that can undergo single addition and uncovering the mechanism and role of their substituents. We have synthesized a library of CPEs with various disubstitution patterns and substituents and systematically investigated their reactivity with Grubbs catalyst. We have found that 1,1-disubstitution of CPE is crucial for both preserving the stability of the propagating chain end and tuning the metathesis reactivity from living polymerization to single addition. The distinct reactivities stemmed from differences in sterics and/or chelation at the Ru alkylidene from C1 substituents after a single CPE ring-opening event, affecting the barrier to propagation. We have utilized the single addition reactivity of CPEs to synthesize alternating copolymers with diverse side chain and backbone functionalities from alternating ROMP of CPE with low-strain cyclic olefins. Recently, we have developed a strategy to precisely place discrete functionalities and side chains via ring-opened CPEs at pre-determined locations along a living ROMP polymer chain, with control over the location and number incorporated. This advance in polymer chemistry opens many exciting opportunities to manipulate the functionalities along well-controlled polymer chains for understanding the effects of their placement and sequence on polymer behaviors, controlling polymer folding/assembly, as well as synthesizing polymers with more complex nonlinear architectures with precision. Our group also recently reported a unique polymechanophore system, polyladderene, that undergoes force-triggered rearrangement into semi-conducting, insoluble polyacetylene. A notable feature in the design was the terminal strained cyclobutene on ladderene that allowed rapid ROMP. We have developed synthetic procedures to prepare triblock copolymers containing mechanically active polyladderene, since block copolymers can self-assemble in solution and bulk and facilitate incorporation of polyladderene with common polymers to impart the dramatic stress-response of polyladderene to diverse materials.
Download or read book Ring opening Polymerization written by and published by . This book was released on 1985 with total page 398 pages. Available in PDF, EPUB and Kindle. Book excerpt:
Download or read book Polymer Synthesis Oxidation Processes written by and published by Springer. This book was released on 2013-10-03 with total page 228 pages. Available in PDF, EPUB and Kindle. Book excerpt: Ring-Opening Polymerization of Bicyclic and Spiro Compounds The Development of Well-defined Catalysts for Ring-Opening Olefin Metathesis CaptodativeOlefins in Polymer Chemistry Synthesis and Properties of Fluorinated Diols Synthesis and Properties of Fluorinated Telechelic Monodis- persedCompounds Synthesis and Metal Complexation of Poly(ethyleneimine) and Derivatives Oxidation of Hydrocarbon Polymers
Download or read book Modification of Polymers written by Charles E. Carraher and published by Springer Science & Business Media. This book was released on 2012-12-06 with total page 414 pages. Available in PDF, EPUB and Kindle. Book excerpt: The sheer volume of topics which could have been included under our general title prompted us to make some rather arbitrary decisions about content. Modification by irradiation is not included because the activity in this area is being treated elsewhere. We have chosen to emphasize chemical routes to modification and have striven to pre sent as balanced a representation of current activity as time and page count permit. Industrial applications, both real and potential, are included. Where appropriate, we have encouraged the contributors to include review material to help provide the reader with adequate context. The initial chapter is a review from a historical perspective of polymer modification and contains an extensive bibliography. The remainder of the book is divided into four general areas: Reactions and Preparation of Copolymers Reactions and Preparation of Block and Graft Copolymers Modification Through Condensation Reactions Applications The chemical modification of homopolymers such as polyvinylchlo ride, polyethylene, poly(chloroalkylene sulfides), polysulfones, poly chloromethylstyrene, polyisobutylene, polysodium acrylate, polyvinyl alcohol, polyvinyl chloroformate, sulfonated polystyrene; block and graft copolymers such as poly(styrene-block-ethylene-co-butylene block-styrene), poly(I,4-polybutadiene-block ethylene oxide), star chlorine-telechelic polyisobutylene, poly(isobutylene-co-2,3-dimethyl- 1,3-butadiene), poly(styrene-co-N-butylmethacrylate); cellulose, dex tran and inulin, is described.
Download or read book Ring opening Polymerization written by Kenneth John Ivin and published by Elsevier Science & Technology. This book was released on 1984 with total page 108 pages. Available in PDF, EPUB and Kindle. Book excerpt:
Download or read book Polymer Synthesis written by and published by Springer Science & Business Media. This book was released on 2004-10-08 with total page 228 pages. Available in PDF, EPUB and Kindle. Book excerpt: 1. T. Takata, N. Kihara, Y. Furusho: Polyrotaxanes and Polycatenanes: Recent Advances in Syntheses and Applications of Polymers Comprising of Interlocked Structures.- 2. M. Suginome, Y. Ito: Transition Metal-Mediated Polymerization of Isocyanides.- 3. K. Osakada, D. Takeuchi: Coordination Polymerization of Dienes, Allenes and Methylenecycloalkanes.
Download or read book Advances in Ring Opening Metathesis Polymerization written by and published by Wiley-VCH. This book was released on 2000-09-12 with total page 0 pages. Available in PDF, EPUB and Kindle. Book excerpt: This volume of Macromolecular Symposia contains contributions presented at the RO(M)P'99 International Symposium in Mons, Belgium. At this meeting, over one hundred chemists, physico-chemists, chemical engineers from the world of academia and industry, as well as students, discussed recent developments in mechanisms and kinetics in RO(M)P, synthesis and characterization of new macromolecular architectures, and new materials and applications via RO(M)P.
Download or read book Bio inspired Polymers written by Nico Bruns and published by Royal Society of Chemistry. This book was released on 2016-10-14 with total page 613 pages. Available in PDF, EPUB and Kindle. Book excerpt: Many key aspects of life are based on naturally occurring polymers, such as polysaccharides, proteins and DNA. Unsurprisingly, their molecular functionalities, macromolecular structures and material properties are providing inspiration for designing new polymeric materials with specific functions, for example, responsive, adaptive and self-healing materials. Bio-inspired Polymers covers all aspects of the subject, ranging from the synthesis of novel polymers, to structure-property relationships, materials with advanced properties and applications of bio-inspired polymers in such diverse fields as drug delivery, tissue engineering, optical materials and lightweight structural materials. Written and edited by leading experts on the topic, the book provides a comprehensive review and essential graduate level text on bio-inspired polymers for biochemists, materials scientists and chemists working in both industry and academia.
Download or read book Cyclic Polymers written by J. A. Semlyen and published by Springer Science & Business Media. This book was released on 2000-08-31 with total page 804 pages. Available in PDF, EPUB and Kindle. Book excerpt: Cyclic Polymers (Second Edition) reviews the many recent advances in this rapidly expanding subject since the publication of the first edition in 1986. The preparation, characterisation, properties and applications of a wide range of organic and inorganic cyclic oligomers and polymers are described in detail, together with many examples of catenanes and rotaxanes. The importance of large cyclics in biological chemistry and molecular biology is emphasised by a wide coverage of circular DNA, cyclic peptides and cyclic oligosaccharides and polysaccharides. Experimental techniques and theoretical aspects of cyclic polymers are included, as well as examples of their uses such as ring opening polymerisation reactions to give commercially important materials. This book covers a wide range of topics which should be of interest to many scientific research workers (for example, in polymer science, chemistry and molecular biology), as well as providing a reference text for undergraduate and graduate students.
