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Showing 1 - 15 of 15 matches in All Departments
The art of using chemical agents for medication dates back into antiquity, although most of the earliest examples used plants, herbs, and other natural materials. The old Egyptian medical papyri, which date from before 1400 B. C., contain dozens of examples of such medicinal plants and animal extracts. In the Old Testament of the Bible, we can find references to using oil to soften the skin and sores (Isaiah 1:6), the use of tree leaves for medicine (Ezekiel 47:12) and various medical balms (Jeremiah 8:22). Not all these recipes were effective in curing the ailments for which they were used and sometimes the treatment was worse than the disease. Nevertheless, the art of using chemical derived agents for medicines continued to develop and received great impetus during the present century with the rise of synthetic organic chemistry. One of the most vexing problems has always been to achieve specifici ty with the medications. While some medical agents do indeed possess a relatively high degree of specificity, most agents are far more systemic than would be desired. Much of the research efforts to correct this deficiency has centered on modifying the chemical agents themselves. Unfortunately, there are severe limitations in this approach since minor modifications often drastically affect the therapeutic activity and can even render the drug completely ineffective, or worse."
Some have predicted that the coming several decades will be the decades of "biotechnology," wherein cancer, birth defects, life span increases, cosmetics, biodegradation, oil spills and exploration, solid waste disposal, and almost every aspect of our material life will be affected by this new area of science. There will also be an extension of emphasis on giant molecules: DNA, enzymes, polysaccharides, lignins, proteins, hemoglobin, and many others. Biotechnology has been defined in various ways. In one sense, this field is older than human history and references to the human use of biotechnology-derived materials can be found in the oldest human writings, such as the Bible. In this book, biotechnology refers to the direct usage of naturally occurring materials or their uses as a feedstock, including the associated biological activities and applications of these materials. Bioactive polymers, on the other hand, are polymers which exert some type of activity on living organisms. These polymers are used in agriculture, controlled release systems, medicine and many other areas. The papers in this book describe polymers which essentially combine features of biotechnology and bioactivity.
Polymer modifications represent a valuable synthetic approach to unique polymer compositions, structure, and properties not readily available by the direct polymerization of monomers. Modified polymeric products already exist in the commercial world (modified celluloses, for example) so the approach is not new. However, it is an interesting and chaU nging opportunity to develop new materials for a variety of specialty applications using the "chemistry on polymers" approach. This book contains papers presented at the symposium on Polymer Modification held at the National American Chemical Society Meeting in Orlando, Florida, August, 1996. The chemistry presented is broad ranging, and includes grafting and chemical oxidation reactions, and many other chemical modifications. Hopefully, the book will be both a resource and an inspiration for the reader to develop new opportunities for his or her particular applications. CONTENTS SURF ACE MODIFICATIONS The Preparation of Methyl Methacrylate/Methacrylic Anhydride Copolymers from PMMA and Dialkyl Amines via Reaction Extrusion . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 3 Michael P. Hallden-Abberton Grafting of Hindered Amine Groups on EPDM and Polyoctenamer via Photo- Hydroperoxidation . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 11 J. Lacoste, S. Chmela, J. Pellet, and J. F. Pilichowski Reactive Gases as Reagents for Polymer Films Chemical Modifications . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 21 J. F. Pilichowski, S. Commereuc, 1. Lukac, G. Teissedre, and J. Lacoste The Synthesis of Hydrophobe-Modified Hydroxyethyl Cellulose Polymers Using Phase Transfer Catalysis . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 31 Emmett M. Partain The Synthesis and Characterization of Polyesters Derived from L-Lactide and Variably-Sized Poly(Caprolactone) . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 45 Michael R. Lostocco and Samuel J.
Although in nature the vast majority of polymers are condensation polymers, much publicity has been focused on functionalized vinyl polymers. Functional Condensation Polymers fulfills the need to explore these polymers which form an increasingly important and diverse foundation in the search for new materials in the twentyfirst century. Some of the advantages condensation polymers hold over vinyl polymers include offering different kinds of binding sites, their ability to be made biodegradable, and their different reactivities with various reagents under diverse reaction conditions. They also offer better tailoring of end-products, different tendencies (such as fiber formation), and different physical and chemical properties. Some of the main areas emphasized include dendrimers, control release of drugs, nanostructure materials, controlled biomedical recognition, and controllable electrolyte and electrical properties.
For there is hope of a tree, If it be cut down, That it will sprout again And that the tender branch Thereof will not cease. Job XIV (7) Mankind has been blessed with a multitude of resources. In the beginning he utilized almost soley replenishable items such as vegetation and animal protein, for both nourishment and shelter. Gradually, such metals as copper and iron were developed and replaced wood as a material of construction. Cement and glass, although more plentiful than other minerals, also replaced the use of growing sub stances. Coal and oil became the primary sources of heat and power. Closer to the focus of this book, petroleum products began to replace the vegetable oils, tannin, wool, cotton, leather, silk, rubber, etc. in a host of applications. Surely, it was argued, the new materials did the job better and cheaper. What they didn't say is that soon we would run out of oil. In any case, research on growing natural products, now called renewable resources, slowed, and these industries sought only to maintain their status quo. The 20th Century saw an unprecedented emphasis and dependence on nonrenewable resources as energy sources (petroleum, coal, ura nium) and the fabric of technology (drugs, clothing, shelter, tires, computer parts). The predawn of the 21st Century brings a reali zation that a cyclic shift back towards the use of renewable re sources for technological application is in order."
Research on metal-containing polymers began in the early 1960's when several workers found that vinyl ferrocene and other vinylic transition metal u -com plexes would undergo polymerization under the same conditions as conventional organic monomers to form high polymers which incorporated a potentially reactive metal as an integral part of the polymer structures. Some of these materials could act as semi-conducters and pos sessed one or two dimensional conductivity. Thus appli cations in electronics could be visualized immediately. Other workers found that reactions used to make simple metal chelates could be used to prepare polymers if the ligands were designed properly. As interest in homo geneous catalysts developed in the late 60's and early 70's, several investigators began binding homogeneous catalysts onto polymers, where the advantage of homo geneous catalysis - known reaction mechanisms and the advantage of heterogeneous catalysis - simplicity and ease of recovery of catalysts could both be obtained. Indeed the polymer matrix itself often enhanced the selectivity of the catalyst."
The first concern of scientists who are interested in synthetic polymers has always been, and still is: How are they synthesized? But right after this comes the question: What have I made, and for what is it good? This leads to the important topic of the structure-property relations to which this book is devoted. Polymers are very large and very complicated systems; their character ization has to begin with the chemical composition, configuration, and con formation of the individual molecule. The first chapter is devoted to this broad objective. The immediate physical consequences, discussed in the second chapter, form the basis for the physical nature of polymers: the supermolecular interactions and arrangements of the individual macromolecules. The third chapter deals with the important question: How are these chemical and physical structures experimentally determined? The existing methods for polymer characterization are enumerated and discussed in this chapter. The following chapters go into more detail. For most applications-textiles, films, molded or extruded objects of all kinds-the mechanical and the thermal behaviors of polymers are of pre ponderant importance, followed by optical and electric properties. Chapters 4 through 9 describe how such properties are rooted in and dependent on the chemical structure. More-detailed considerations are given to certain particularly important and critical properties such as the solubility and permeability of polymeric systems. Macromolecules are not always the final goal of the chemist-they may act as intermediates, reactants, or catalysts. This topic is presented in Chapters 10 and 11."
''A must for anyone interested in metal-containing polymers and all its aspects.'' ---American Scientist ''Nicely organized...well-written....An excellent shapshot of the current state of this field.'' ---MRS Bulletin, July 1998
Research on metal-containing polymers began in the early 1960's when several workers found that vinyl ferrocene and other vinylic transition metal TI -complexes would undergo polymerization under the same conditions as conventional organic monomers to form high polymers which incorporated a potentially reactive metal as an integral part of the polymer structures. Some of these materials could act as semi conductors and possessed one or two dimensional conductivity. Thus applications in electronics could be visualized immediately. Other workers found that reactions used to make simple metal chelates could be used to prepare polymers if the ligands were designed properly. As interest in homogeneous catalysts developed in the late 60's and early 70's, several investigators began binding homogeneous catalysts onto polymers, where the advantage of homogeneous catalysis - known reaction mechanisms and the advantage of heterogeneous catalysis - simplicity and ease of recovery of catalysts could both be obtained. Indeed the polymer matrix itself often enhanced the selectivity of the catalyst. The first symposium on Organometallic Polymers, held at the National Meeting of the American Chemical Society in September 1977, attracted a large number of scientists interested in this field, both established investigators and newcomers. Subsequent symposia in 1977, 1979, 1983, and 1987 have seen the field mature. Hundreds of papers and patents have been published."
Although in nature the vast majority of polymers are condensation polymers, much publicity has been focused on functionalized vinyl polymers. Functional Condensation Polymers fulfills the need to explore these polymers which form an increasingly important and diverse foundation in the search for new materials in the twentyfirst century. Some of the advantages condensation polymers hold over vinyl polymers include offering different kinds of binding sites, their ability to be made biodegradable, and their different reactivities with various reagents under diverse reaction conditions. They also offer better tailoring of end-products, different tendencies (such as fiber formation), and different physical and chemical properties. Some of the main areas emphasized include dendrimers, control release of drugs, nanostructure materials, controlled biomedical recognition, and controllable electrolyte and electrical properties.
Polymer modifications represent a valuable synthetic approach to unique polymer compositions, structure, and properties not readily available by the direct polymerization of monomers. Modified polymeric products already exist in the commercial world (modified celluloses, for example) so the approach is not new. However, it is an interesting and chaU nging opportunity to develop new materials for a variety of specialty applications using the "chemistry on polymers" approach. This book contains papers presented at the symposium on Polymer Modification held at the National American Chemical Society Meeting in Orlando, Florida, August, 1996. The chemistry presented is broad ranging, and includes grafting and chemical oxidation reactions, and many other chemical modifications. Hopefully, the book will be both a resource and an inspiration for the reader to develop new opportunities for his or her particular applications. CONTENTS SURF ACE MODIFICATIONS The Preparation of Methyl Methacrylate/Methacrylic Anhydride Copolymers from PMMA and Dialkyl Amines via Reaction Extrusion . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 3 Michael P. Hallden-Abberton Grafting of Hindered Amine Groups on EPDM and Polyoctenamer via Photo- Hydroperoxidation . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 11 J. Lacoste, S. Chmela, J. Pellet, and J. F. Pilichowski Reactive Gases as Reagents for Polymer Films Chemical Modifications . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 21 J. F. Pilichowski, S. Commereuc, 1. Lukac, G. Teissedre, and J. Lacoste The Synthesis of Hydrophobe-Modified Hydroxyethyl Cellulose Polymers Using Phase Transfer Catalysis . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 31 Emmett M. Partain The Synthesis and Characterization of Polyesters Derived from L-Lactide and Variably-Sized Poly(Caprolactone) . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 45 Michael R. Lostocco and Samuel J.
Some have predicted that the coming several decades will be the decades of "biotechnology," wherein cancer, birth defects, life span increases, cosmetics, biodegradation, oil spills and exploration, solid waste disposal, and almost every aspect of our material life will be affected by this new area of science. There will also be an extension of emphasis on giant molecules: DNA, enzymes, polysaccharides, lignins, proteins, hemoglobin, and many others. Biotechnology has been defined in various ways. In one sense, this field is older than human history and references to the human use of biotechnology-derived materials can be found in the oldest human writings, such as the Bible. In this book, biotechnology refers to the direct usage of naturally occurring materials or their uses as a feedstock, including the associated biological activities and applications of these materials. Bioactive polymers, on the other hand, are polymers which exert some type of activity on living organisms. These polymers are used in agriculture, controlled release systems, medicine and many other areas. The papers in this book describe polymers which essentially combine features of biotechnology and bioactivity.
The art of using chemical agents for medication dates back into antiquity, although most of the earliest examples used plants, herbs, and other natural materials. The old Egyptian medical papyri, which date from before 1400 B. C., contain dozens of examples of such medicinal plants and animal extracts. In the Old Testament of the Bible, we can find references to using oil to soften the skin and sores (Isaiah 1:6), the use of tree leaves for medicine (Ezekiel 47:12) and various medical balms (Jeremiah 8:22). Not all these recipes were effective in curing the ailments for which they were used and sometimes the treatment was worse than the disease. Nevertheless, the art of using chemical derived agents for medicines continued to develop and received great impetus during the present century with the rise of synthetic organic chemistry. One of the most vexing problems has always been to achieve specifici ty with the medications. While some medical agents do indeed possess a relatively high degree of specificity, most agents are far more systemic than would be desired. Much of the research efforts to correct this deficiency has centered on modifying the chemical agents themselves. Unfortunately, there are severe limitations in this approach since minor modifications often drastically affect the therapeutic activity and can even render the drug completely ineffective, or worse."
Introduction to Polymer Chemistry provides undergraduate students with a much-needed, well-rounded presentation of the principles and applications of natural, synthetic, inorganic, and organic polymers. With an emphasis on the environment and green chemistry and materials, this fourth edition continues to provide detailed coverage of natural and synthetic giant molecules, inorganic and organic polymers, elastomers, adhesives, coatings, fibers, plastics, blends, caulks, composites, and ceramics. Building on undergraduate work in foundational courses, the text fulfills the American Chemical Society Committee on Professional Training (ACS CPT) in-depth course requirement
Carraher's Polymer Chemistry, Tenth Edition integrates the core areas of polymer science. Along with updating of each chapter, newly added content reflects the growing applications in Biochemistry, Biomaterials, and Sustainable Industries. Providing a user-friendly approach to the world of polymeric materials, the book allows students to integrate their chemical knowledge and establish a connection between fundamental and applied chemical information. It contains all of the elements of an introductory text with synthesis, property, application, and characterization. Special sections in each chapter contain definitions, learning objectives, questions, case studies and additional reading.
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